COOLING UNIT FOR POWER MODULES

Abstract

Cooling power modules used in high-power systems such as three-phase inverters can require a cooling device that is heavier than desired for some applications, such as electric vehicles. A cooling device is disclosed that can provide sufficient cooling in a weight-reduced package. Furthermore, assembly methods are disclosed that make the cooling device more robust against shocks and vibrations to which electric vehicles may be subjected.

Description

CROSS-REFERENCE TO RELATED REGISTRATION

[0001] This application takes advantage of the preliminary U.S. application No. 63 / 698,837, filed on September 25, 2024, which is hereby incorporated by reference in its entirety. AREA OF REVELATION

[0002] The disclosure relates to electronic cooling and, more specifically, to a cooling device (i.e., a cooler) for one or more power modules. BACKGROUND

[0003] Power modules can be used in an electric vehicle system. For example, a power module might be a half-bridge circuit configured to output an alternating current (AC) signal, and an electric vehicle drive inverter might use three power modules to generate three-phase AC power to drive an electric motor. Switching the half-bridge circuit, which can be performed using power transistors, can occur at power levels in the kilowatt range. Therefore, active liquid cooling may be necessary to dissipate the heat generated by these systems. SUMMARY

[0004] A cooling device is disclosed which can provide heat dissipation to prevent overheating of the power modules without being too bulky or expensive. Furthermore, the cooler uses an adhesive (e.g., a sealant) to achieve the mechanical strength required to withstand the shocks and vibrations associated with vehicles.

[0005] In some aspects, the techniques described herein relate to a cooling device for a power module, wherein the cooling device includes: a body, including: a basin with a lower surface offset by a depth to an upper surface; and a cover coupled (e.g., bonded) to the upper surface of the body by an adhesive (e.g., adhesive sealant), wherein the cover includes: a first layer of material facing the basin; and a second layer of material facing the power module.

[0006] In some aspects, the techniques described herein relate to a three-phase inverter comprising: a first power module; a second power module; a third power module; and a heat sink coupled to the first power module, the second power module, and the third power module, the heat sink comprising: a body, including: a basin with a lower surface offset by a depth to an upper surface; and a groove in the upper surface surrounding the basin; and a cover coupled (e.g., bonded) to the upper surface of the body by an adhesive (e.g., sealant) arranged in the groove, the cover comprising: a first metal layer facing the basin; and a second metal layer facing the first power module, the second power module, and the third power module.

[0007] In some aspects, the techniques described herein relate to a process that includes: attaching a power module to a copper layer of a cover, wherein the cover encloses the copper layer on a top side facing the power module and an aluminum layer on a bottom side opposite the top side; metered dispensing of adhesive (e.g., adhesive sealant) into a groove in a top surface of a body, wherein the groove surrounds a basin defined by the body, the basin having a bottom surface offset by a depth relative to the top surface; and bonding the bottom of the cover to the top surface of the body with the adhesive (e.g., adhesive sealant) such that the aluminum layer faces the basin.

[0008] The foregoing illustrative summary, as well as other exemplary aims and / or benefits of the disclosure and the manner in which they are achieved, are further explained in the following detailed description and in the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a perspective view of a system that includes power modules and a cooling device, according to a possible implementation of the present disclosure. Fig. Figure 2 is a perspective exploded view of a cooling device according to one possible implementation of the present disclosure. Fig. Figure 3A is an exploded view, viewed from the side, of a section of a cooling device according to one possible implementation of the present disclosure. Fig. 3B is a cross-sectional view of the in Fig. 3A Cover shown according to a possible implementation of the present disclosure. Fig. 3C is another cross-sectional view of the in Fig. 3A Cover shown according to a possible implementation of the present disclosure. Fig. Figure 4 is a cross-sectional view of the cooling device with an insertion illustrating details of a groove for adhesive (e.g., adhesive sealant) according to one possible implementation of the present disclosure. Fig. Figure 5A is a side view of a power module according to one possible implementation of the present disclosure. Fig. Figure 5B illustrates the placement of the power module on the cooling device according to one possible implementation of the present disclosure. Fig. Figure 6 illustrates a method for assembling a three-phase inverter with a cooling device according to a possible implementation of the present disclosure. Fig. Figure 7 is a flowchart of a method for assembling a three-phase inverter according to a possible implementation of the present disclosure.

[0009] The components in the drawings are not necessarily to scale with respect to each other. The same reference symbols denote corresponding parts in the different views. DETAILED DESCRIPTION

[0010] In power electronics packaging, a cooling device (i.e., a heat sink) can be included to provide thermal management for a power module (or modules). For example, power modules can be mounted to a heat sink so that the heat generated by the circuitry of the power modules (e.g., IGBT, MOSFET, diodes, inductors, transformers, etc.) can be absorbed by the heat sink. The amount / rate of heat absorption can be based on the heat sink's thermal conductivity and mass, and a fluid (e.g., water, dielectric fluid) can be pumped through the heat sink to enhance cooling.

[0011] As cooling requirements increase, a conventional radiator made of only one material (e.g., copper) can become too heavy and too expensive for some applications, such as electric vehicles. The present disclosure addresses this first technical problem with a cooling device that incorporates a cover incorporating different materials to balance thermal conductivity and weight.

[0012] In electric vehicles, accidents can cause shocks and vibrations that are more severe than in other applications. A second technical problem with conventional radiators that rely solely on fasteners is their ability to withstand car crashes without leaking at a seam formed by the cover. The present disclosure addresses this second technical problem with a cooling device whose cover is coupled (e.g., bonded) to a body using an adhesive (e.g., an adhesive sealant) to make the radiator more mechanically robust.

[0013] The disclosed cooling device can be used with at least one power module. For the purposes of this document, "power module" can refer to a semiconductor package that includes at least one semiconductor die. In one possible implementation, a semiconductor die enclosed in a power module can include a transistor, such as a metal-oxide-semiconductor field-effect transistor (MOSFET) or an insulated-gate bipolar transistor (IGBT).

[0014] The semiconductor die can be implemented using a single semiconductor material, such as silicon (Si). The semiconductor die can also be implemented using a compound semiconductor material. The compound semiconductor material can be a combination of elements from Group III of the periodic table (e.g., silicon, oxide, ferrous ...

[0015] Aluminum, gallium, indium, etc.) with elements from Group V of the periodic table (e.g., nitrogen, arsenic, etc.). In one possible implementation, the power module die can be implemented using gallium nitride (GaN). To improve its performance, the semiconductor die can also be implemented as a silicon-containing chemical compound. For example, dies implemented using silicon carbide (SiC) can exhibit a large bandgap, making them suitable for high-power, high-temperature, and high-frequency devices (e.g., transistors).

[0016] A power module can include multiple semiconductor dies that may be electrically coupled to form a circuit. In one possible implementation, the power module includes a half-bridge circuit composed of two transistors connected in series across a positive and negative input. Each of the two transistors can be implemented as a semiconductor die. The two semiconductor dies can be coupled to a substrate for electrical interconnection and cooling. The substrate includes conductors (e.g., traces, pads, wires, etc.) to form the electrical connections required for the half-bridge circuit and to provide connection points for external connections. The conductors can be implemented using a metal (e.g., gold, silver, aluminum, etc.), and the conductors can form patterns (e.g., traces, pads) on a surface (e.g.,form on the upper surface, lower surface) of the substrate or on intermediate layers of the substrate.

[0017] In one possible implementation, the substrate of a power module can be a directly bonded metal substrate (DBM substrate) that includes an insulating layer between two metal layers. For example, a directly bonded copper substrate (DBC substrate) can enclose the insulating layer located between a first copper layer and a second copper layer. The insulating layer can be, for example, a ceramic layer. In some implementations, the ceramic layer is a ceramic material such as aluminum oxide (Al₂O₃) or aluminum nitride (AlN), or includes one.

[0018] In some implementations, the first metal layer and / or the second metal layer may be coupled to a heat sink. In one possible implementation, a section of the first or second metal layer may be exposed through a molding compound containing the power module die, and this section may be coupled to the cooling device.

[0019] The molding compound can serve as a protective outer shell for the power module. In some implementations, the molding compound (i.e., the molding material, encapsulation material) is a non-conductive material, such as an epoxy resin, that can be formed (applied, etc.) through an injection molding or compression molding process. In some implementations, the molding compound may enclose a separate plastic housing that is enclosed within the power module assembly.

[0020] The power module can include one or more wire bonds to connect the semiconductor die (or dies) to a connection frame. The connection frame can include pins, connectors, tabs, or pads to couple the power module externally. In one possible implementation, one or more of the wire bonds can be replaced by a conductive clip. The conductive clip can be coupled to another component (e.g., a mounting pad, a connection frame, a semiconductor die, etc.) using a soldering process, a sintering process, or a metal-to-metal bonding process.

[0021] The soldering process can involve joining two surfaces (e.g., metal surfaces) using a molten metal alloy, which may include tin (Sn), lead (Pb), silver (Ag), and / or copper (Cu). The sintering process can involve uniting materials into a solid mass by using, for example, a combination of pressure and / or heat, without melting the materials. In some implementations, sintering may involve fusing a material (e.g., a powdered material) into a solid or porous mass by heating, and typically also compressing the material without liquefaction. In some implementations, the materials usable for sintering may include metals such as silver (Ag), copper (Cu), and / or metal alloys.

[0022] Fig. Figure 1 is a perspective view of a system 100, which includes power modules and a cooling device, according to a possible implementation of the present disclosure. As shown, the plurality of modules can include a first power module 101, a second power module 102, and a third power module 103. Each of the power modules can be nominally identical (i.e., based on a common design) and can include power electronics configured for high voltages (e.g., > 100 volts) and high currents (e.g., > 20 amperes).

[0023] In one possible implementation, System 100 is an inverter (e.g., a three-phase inverter), and each power module is configured to receive a direct current (DC) voltage and to output an alternating current (AC) signal corresponding to one of the three phases. In another possible implementation, the input of the power modules is connected to an electric vehicle (EV) battery, and the outputs of the power modules are connected to the windings of a motor (e.g., the traction motor) of an EV. In yet another possible implementation, each power module includes a half-bridge circuit comprising two transistors connected in series across the DC voltage.

[0024] System 100 may also include an add-on module (or multiple modules) 110, which may, but need not, include power electronics. In one possible implementation, the add-on module 110 is an excitation module configured to generate a steady-state (DC) magnetic field for the motor of an electric vehicle. In some implementations, System 100 may include more or fewer power modules than shown. Fig. 1 shown. In some implementations, the additional module 110 may be omitted.

[0025] In some implementations, the add-on module 110 may have a size (e.g., a footprint, viewed from above) and / or shape (e.g., thickness, width, length) that differs from the size and / or shape of one or more of the power modules 101, 102, and 103. In other implementations, one or more of the power modules 101, 102, and 103 may have the same or different size and / or shape. For example, power module 101 may have a size and shape that is identical to the size and shape of power module 102. As another example, power module 101 may have a size and / or shape that differs from the size and / or shape of power module 102.

[0026] System 100 further includes a cooling unit 200, which is coupled to the power modules (and the auxiliary module 110). The cooling unit 200 may include an inlet port (not shown) configured to receive a fluid (e.g., a pressurized fluid) and an outlet port (not shown) configured to discharge the fluid (e.g., the pressurized fluid). In one possible implementation, the inlet and outlet ports of the cooling unit 200 may be coupled to a cooling system (e.g., fluid pump, radiator, etc.) of the electric vehicle.

[0027] The cooling device 200 can be shaped to support the power modules arranged in a row. Accordingly, the length of the cooling device 200 can be greater than the length of each power module (e.g., 250 mm), and the width of the cooling device 200 can be approximately equal to the width of each power module (e.g., 60 mm). In one possible implementation, the first power module 101, the second power module 102, and the third power module 103 are coupled to an upper surface of the cooling device 200, while the inlet and outlet ports are located in a lower surface of the cooling device 200. In another possible implementation, the cooling device can include a variety of mounting features to integrate (i.e., connect) the cooling device to the electric vehicle.

[0028] In one possible implementation, each fastening feature 120 includes a flange that has an opening (e.g., a through-hole) configured to receive a fastener (e.g., a screw). In some implementations, the fastening feature 120 may be configured to receive a variety of coupling elements, such as a clip, a press fitting, a rivet, and / or so on. In some implementations, the cooling device 200 may include more or fewer fastening features than in Fig. Figure 1 shows that in some implementations, the fastening feature 120 can be a tab.

[0029] Fig. Figure 2 is a perspective exploded view of the cooling device 200 according to a possible implementation of the present disclosure. Fig. 2 is oriented such that features (e.g., surfaces) described as "top," "above," "higher," etc., are closer to the top of the page than features described as "bottom," "below," "lower," etc. Furthermore, features (e.g., edges) described as "inside" are closer to the center of the page than features described as "outside." This convention is used for all figures unless otherwise specified.

[0030] As in Fig. As shown in Figure 2, the cooling device 200 includes a body 210 and a cover 250. A lower surface of the cover 250 faces an upper surface 211 of the body 210 (e.g., exposed). An upper surface of the cover 250 can include a plurality of raised areas for (e.g., thermal) connection to pads of the plurality of power modules. For example, a first raised area 251, a second raised area 252, and a third raised area 253 can each be configured to attach to corresponding pads on the lower surfaces of the first power module 101, the second power module 102, and the third power module 103, respectively. In one possible implementation, the attachment can involve soldering or sintering the pads of the power modules to the raised areas of the cover 250.In some implementations, one or more of the raised areas 251, 252 and 253 may be planar, with one or more channels or depressions around the raised areas 251, 252 and 253, so that they are raised relative to the channel.

[0031] In some implementations, sintering can be a process of fusing particles into a solid mass by using, for example, a combination of pressure and / or heat, or it can include this process without melting the materials. In some implementations, sintering can involve fusing a material (e.g., a powdered material) into a solid or porous mass by heating, and usually also compressing the material without liquefaction. In some implementations, the materials usable for sintering can include metals such as silver (Ag), copper (Cu), and / or metal alloys. In some implementations, sintered compounds can exhibit desirable electrical and / or thermal conductivity, durability, and a relatively high melting point.

[0032] In some implementations, one or more of the components described herein can be coupled using materials such as a solder, a sintered material (e.g., silver, copper material) and / or other metal-to-metal bonding materials.

[0033] In some implementations, coupling of components can be carried out, for example, using a soldering process, a sintering process (e.g., a silver sintering process, a copper sintering process) and / or other metal-to-metal joining processes.

[0034] The body 210 of the cooling device 200 encloses a basin 230 (which can also be referred to as a cavity) with a lower surface offset by a depth 214 relative to the upper surface 211. When the cover is attached to the body 210, the basin 230 and the cover 250 define a reservoir configured to contain a fluid (i.e., coolant). The fluid in the reservoir can flow between an inlet opening 212 in the lower surface of the basin 230 and an outlet opening 213 in the lower surface of the basin 230. The inlet opening 212 allows the fluid to flow in through an inlet pipe nipple 222 extending from a lower surface of the body 210. Similarly, the outlet opening 213 allows the fluid to flow out through an outlet pipe nipple 223 extending from the lower surface of the body 210.In one possible implementation, the inlet pipe nipple 222 and the outlet pipe nipple 223 can enable connection to cooling hoses of an electric vehicle.

[0035] The body 210 of the cooling device 200 further includes a groove 220 in the upper surface 211, which surrounds the basin 230. As in Fig. As shown in Figure 2, the groove 220 can be uniformly offset from an outer edge of the basin 230, such that a section of the upper surface 211 is located between the groove 220 and the basin 230. The groove 220 is configured to receive and contain an adhesive (e.g., adhesive sealant) so that the cover 250 can be coupled (e.g., bonded) to the body 210 using the adhesive (e.g., adhesive sealant) located in the groove 220. The adhesive (e.g., adhesive sealant) and the groove 220 can also provide a seal to prevent the fluid from escaping the reservoir. Accordingly, the adhesive (e.g., adhesive sealant) can have a bond strength sufficient to withstand the pressure of the fluid used to generate a flow rate (e.g., 5 to 10 l / min) for cooling.

[0036] In some implementations, the groove 220 may run continuously around the basin 230. In other implementations, the groove 220 may not run continuously around the basin 230.

[0037] In one possible implementation, the cover 250 can further be attached to the body 210 by fasteners (e.g., screws 260). Accordingly, the body 210 can include openings that provide space for the threaded sections of the screws 260, while the cover 250 can include threaded openings that mesh with the threads of the screws 260. As shown in Fig. As shown in Figure 2, any opening 261 can be located between an outer edge of the groove 220 and an outer edge of the upper surface 211. The seal created by the adhesive (e.g., sealant) and the screws 260 may be stronger than a seal created by an O-ring and fasteners. For this reason, the cooling device 200 may not include an O-ring.

[0038] In some implementations, one or more of the fasteners can be referred to as the coupling mechanism. Although shown as an example of a screw 260, in some implementations one or more of the fasteners may be, for example, a clip, a screw, a press fitting, a rivet, and / or so forth.

[0039] Fig. Figure 3A is an exploded view, seen from the side, of a section of a cooling device according to one possible implementation of the present disclosure. As shown, the cover 250 can enclose a plurality of pins 256. The pins 256 can be of the same size (e.g., height, diameter) or of different sizes. The pins 256 can have a circular or non-circular cross-section. The plurality of pins 256 can be arranged in one or more patterns (e.g., grid, staggered grid). The plurality of pins 256 is configured to extend from a lower surface 255 of the cover 250 into the basin 230 (i.e., reservoir) when the cover 250 is attached to the body 210. As a result, the plurality of pins 256 can increase the area of ​​the cover in contact with the fluid.The increased surface area can improve the thermal conductivity of a thermal path from the power module, through the cover, to the fluid.

[0040] As in Fig. As shown in Figure 3A, the cover 250 further includes a second raised area 254 for each power module, illustrating that each power module can include multiple pads for connection to the cover 250. In one possible implementation, sections of the upper surface of the cover 250 are removed to define the raised areas. In other words, the raised areas (i.e., plateau areas, base areas) can be created by removing sections of the cover 250 around the raised areas. For example, sections of the cover 250 can be removed, allowing one or more channels 281 to be formed at least partially or completely around the raised areas, thus defining the raised areas. Put another way, the raised areas can be mesas defined by one or more depressions within the cover 250.The one or more depressions may be located at least partially or completely around the raised areas.

[0041] The raised areas can be shaped (e.g., rectangular) and sized to fit the pads of the power modules and can be plated with one or more metals to facilitate soldering or sintering. In one possible implementation, the raised areas can be plated with a layer of nickel to prevent corrosion. In another possible implementation, a layer of silver can be plated over the nickel layer (e.g., in the raised areas) to facilitate soldering.

[0042] Fig. 3B is a cross-sectional view of the in Fig. 3A Coverage shown according to a possible implementation of the present disclosure. As in Fig. As shown in Figure 3B, the cover 250 of the cooling device can include a first material layer and a second material layer. The material layers can be different materials (e.g., different metals) selected according to thermal conductivity and weight for a specific application (e.g., electric vehicle).

[0043] As in Fig. As shown in Figure 3B, the cover 250 can enclose a first metal layer 271 (i.e., lower metal layer) configured to face the basin 230 when the cover 250 is attached to the body 210. The cover 250 can further include a second metal layer 272 (i.e., upper metal layer) configured to face the power modules when the power modules are attached to the cover 250. The cover 250 includes raised areas 251 and 254. As shown, the layers are arranged in a vertical stack such that the lower surface of the second metal layer 272 is in contact with the upper surface of the first metal layer 271.The metal layers can be bonded together to form a monolithic covering using one or more processes, which may include one or more plating processes, plating welding processes, sintering processes, and / or sputtering processes. For example, pressure and heat can be applied over a period of time to bond the metal layers.

[0044] As in Fig. As shown in Figure 3B, the first metal layer 271 has a first thickness 276, and the second metal layer 272 has a second thickness 277. In a first possible implementation, the first thickness 276 is greater than the second thickness 277. In a second possible implementation, the first thickness 276 is less than the second thickness 277. In a third possible implementation, the first thickness 276 is equal to the second thickness 277.

[0045] In some implementations, the second thickness 277 can be four times thinner than the first thickness 276. In some implementations, the second thickness 277 can be less than four times thinner than the first thickness 276. In some implementations, the second thickness 277 can be more than four times thinner than the first thickness 276.

[0046] In some implementations, the first thickness 277 can be four times thicker than the second thickness 277. In some implementations, the first thickness 277 can be less than four times thicker than the second thickness 277. In some implementations, the first thickness 277 can be more than four times thicker than the second thickness 277.

[0047] The thickness of each layer can be based on a desired weight of the cover 250 and on one or more desired thermal properties of the cover 250 (e.g., thermal resistance, thermal conductivity, heat capacity, coefficient of thermal expansion (CTE), etc.). In one possible implementation, the thickness of each layer is chosen such that the weight of the cover 250 is minimized for a given thermal conductivity.

[0048] As in Fig. As shown in Figure 3B, the raised area 251 (along plane A) is planar with the raised area 254 and other parts of the cover 250. In some implementations, the raised area 254 may be higher than the raised area 251. In some implementations, the raised area 254 may be lower than the raised area 251. In some implementations, the raised area 251 and the raised area 254 may be lower than other sections of the cover 250.

[0049] In some implementations, the raised area 251 and / or the raised area 254 may be lower or higher than other sections (e.g., page section 257) of the cover 250. This example implementation is at least in Fig. 3C shown. In the Fig. In the implementation shown in Figure 3C, section 257 has a height that differs from the height of raised area 251 and / or raised area 254. Raised area 251 and / or raised area 254 have a different height than the lower surface of channel 281.

[0050] In some implementations, the thickness of section 257 above level P may be different (e.g., greater or lesser) than the depth of channel 281 below level P. In some implementations, the thickness of section 257 above level P may be equal to the depth of channel 281 below level P.

[0051] In some implementations, the first metal layer 271 can be a metal different from a metal in the second metal layer 272. In one possible implementation, the first metal layer 271 (i.e., the bottom metal layer) is aluminum (Al), and the second metal layer 272 (i.e., the top metal layer) is copper (Cu). The aluminum layer (i.e., the first thickness 276) can be thicker than the copper layer (i.e., the second thickness 277) to reduce the weight of the cover 250, thereby reducing the overall weight of the system 100 (see Fig. 1) can be reduced. As shown, the multitude of pins 256 extends from a lower surface 255 of the first metal layer 271.

[0052] Fig. Figure 4 is a cross-sectional view of the cooling device 200 with an inset illustrating details of the groove 220 for adhesive (e.g., sealant) according to one possible implementation of the present disclosure. As previously described, the cover 250 can include a first metal layer 271 facing the reservoir and a second metal layer 272 to which a power module (or power modules) can be attached. In one possible implementation, the body 210 is the same material as one of the metal layers (e.g., Al). In another possible implementation, the body 210 can be a different material. For example, the body can be a non-metallic material, including (but not limited to) ceramics, FR-4, phenols, glass fibers, graphite, or a combination thereof.

[0053] Fig. Figure 4 includes an insertion 410, which illustrates a cross-section of the groove. As shown, the cross-section of the groove 220 can include a distribution section 411 configured to receive an adhesive (e.g., adhesive sealant). The distribution section 411 can have a conical shape to form a conical gap between the first metal layer 271 (i.e., the bottom metal layer) of the cover and the body 210. The adhesive (e.g., adhesive sealant) can be introduced into the distribution section 411 using a variety of dispensing methods, including (but not limited to) needle dispensing, nozzle dispensing, and jet dispensing.

[0054] The amount of adhesive dispensed can be selected such that the adhesive bonds the first metal layer 271 to the body 210 when the cover is attached to the body. To accommodate variations in the amount of adhesive dispensed, the cross-section of the groove 220 can include an overflow section 412. The overflow section 412 can be rectangular in shape to form a right-angled gap between the first metal layer 271 (i.e., the bottom metal layer) of the cover and the body 210. The adhesive (e.g., sealant) can fill the overflow section 412 (e.g., be squeezed into it) when the cover 250 is joined to the body 210 (e.g., using screws 260).

[0055] As shown, the cross-section of the groove 220 can be offset to an outer edge 414 of the basin to form a sealing section 413 of the groove 220. In the sealing section 413, the upper surface of the body 210 is in direct contact with the first metal layer 271 of the cover 250. The sealing section can create a seal so that the fluid, which may be under pressure, does not escape from the reservoir and the sealant does not enter the reservoir. This seal can be reinforced by a bonding force resulting from the screws 260 and the adhesive (e.g., sealant).

[0056] Fig. Figure 5A is a side view of a power module according to one possible implementation of the present disclosure. The power module 500 can include several dies 520, which can be electrically coupled to a substrate 530. The substrate 530 can include conductors (e.g., traces, pads, wires, vias, etc.) to form the electrical connections required to create a circuit (e.g., a half-bridge circuit), to connect to a terminal frame 510 for external electrical connections, and to provide a thermal connection to the cooling device. The terminal frame, the dies, and the substrate can be encapsulated by encapsulation material 540. In one possible implementation, the encapsulation material can include openings that expose pads on a lower surface of the power module.In one possible implementation, the lower surface of the power module 500 includes a first pad 531 and a second pad 532.

[0057] As mentioned above, the power module 500 can enclose one or more DBM substrates. A surface of one or more of the DBM substrates can be exposed through the power module as the first pad 531 and / or second pad 532.

[0058] In some implementations, a DBM substrate can be formed by bonding one or more of the metal layers (e.g., first metal layer, second metal layer) to the insulating layer. In some implementations, one or more of the metal layers can be bonded to the insulating layer, for example, using a high-temperature process.

[0059] In some implementations, the first and / or second metal layer of the DBM substrate can be or function as a heat sink. In some implementations, the first and / or second metal layer can be coupled to a heat sink. In some implementations, at least a portion of one or more of the first or second metal layers can be exposed by a molding material.

[0060] In some implementations, the first and / or second metal layer of the DBM substrate may be or include a structured metal layer that incorporates one or more electrically conductive traces. In some implementations, the first and / or second metal layer may be or include a structured layer configured to form one or more electrical circuits, one or more conductive vias (both reactive and / or through-holes), and / or so forth.

[0061] In some implementations, the DBM substrate may be or include a directly bonded copper substrate (DBC substrate) (e.g., a DBM with copper metal layers). In some implementations, such as DBC substrate implementations, the first metal layer and / or the second metal layer is a copper layer.

[0062] In some implementations, one or more semiconductor dies (e.g., one or more semiconductor components) may be or include a power semiconductor die. In some implementations, one or more semiconductor dies may be (e.g., be part of) or include one or more metal-oxide-semiconductor field-effect transistors (MOSFETs), an insulated-gate bipolar transistor (IGBT), an integrated circuit (IC), an inverter, a power conversion circuit, a bridge circuit, a fast diode (FRD), a diode, and / or so forth. In some implementations, one or more semiconductor dies may be (e.g., be part of) or include a component for an electric vehicle (EV).

[0063] More than one semiconductor die can be included in the implementations described herein. In some implementations, different semiconductor dies (where more than one semiconductor die is included) can be fabricated using different semiconductor substrates (e.g., a silicon carbide substrate (SiC substrate), a silicon substrate (Si substrate), a gallium nitride substrate (GaN substrate), etc.). In other words, the different semiconductor dies can be fabricated on different semiconductor wafers or materials, for example. This can be referred to as a hybrid die configuration. For example, a first semiconductor die can be formed using a SiC substrate, and a second semiconductor die (separate from the first semiconductor die) can be formed using a silicon substrate.As another example, an IGBT can be manufactured using a SiC substrate, while a controller can be manufactured using a silicon substrate.

[0064] In example implementations, a first semiconductor die can be connected to a second semiconductor die, for instance, by an electrical connection (e.g., a wire bond, an electrical clip connection) extending directly from the first die to the second die, or by a conductor formed in the first conductive layer (e.g., a metal layer) of the power electronics substrate. The first of the multiple semiconductor dies can also be connected to terminal frame posts by electrical connections such as wire bonds or clips.

[0065] In exemplary implementations, a package (e.g., a power module) can be a hybrid device package that includes a semiconductor die or a multitude of semiconductor dies integrated on a unifying power electronics substrate (e.g., a ceramic substrate, a DBM substrate, a DBC substrate, or an AMB substrate). In some implementations, multiple semiconductor devices (e.g., fabricated on the same substrate, such as a SiC substrate) may be suitable for high-power applications.

[0066] In some implementations, one or more of the power modules may include one or more connector frame structures. Although referred to as a connector frame by way of example in at least some sections of this detailed description, the connector frame can include any type of conductive section of a package (e.g., conductive section, conductive connector) that can provide an external connection point from a package. Accordingly, the connector frame can be referred to as the conductive section of the package.

[0067] In some implementations, one or more sections of a connection frame can be coupled to a pad (e.g., a bond pad) on at least one section of a DBM substrate.

[0068] The power modules described herein can include a variety of signal connections. These signal connections can be power connections, input signal connections, output signal connections, and so on. In some implementations, the signal connections can be enclosed within a connection frame. In some implementations, a connection frame can include any type of conductive section of a package (e.g., conductive section, conductive connection) that can provide an external connection point from the package. Accordingly, a connection frame can be referred to as a conductive section of a package or assembly. In some implementations, one or more sections of a connection frame can be coupled to a pad (e.g., a bond pad) on at least one section of a DBM substrate and / or a semiconductor die.

[0069] One or more wire bonds, which may be included in at least some of the implementations described herein, can be replaced by a conductive component. For example, in some implementations, one or more wire bonds can be replaced by a conductive clip. The conductive clip can be coupled to another component (e.g., a mounting pad, a terminal frame, a semiconductor die, and / or so forth) by, for example, using solder (e.g., a soldering process), sinter coupling (e.g., a sintering process), a weld, and / or so forth. In some implementations, one or more wire bonds and / or clips can function as input and / or output power connectors, signal connectors, power connectors, etc.

[0070] In some implementations, one or more semiconductor dies may be embedded (rather than surface-mounted) in a layer within the context of the power module implementations described herein. For example, one or more semiconductor dies may be arranged in a recess (which may be a cavity or also be referred to as such) within a layer (e.g., a substrate, a printed circuit board, a conductive layer, or an insulating layer).

[0071] In some implementations, one or more of the power modules may contain a separate module (e.g., a package containing a semiconductor device). The power module may be referred to as a package. For example, one or more modules may be one or more submodules enclosed within the power module. In other words, a first module may be enclosed as a submodule within a second module.

[0072] Fig. Figure 5B illustrates the placement of the power module 500 on the cooling device 200 according to one possible implementation of the present disclosure. As shown, the first pad 531 can be positioned on the first raised area 251, and the second pad 532 can be positioned on the second raised area 254 to establish a mechanical (and electrical) connection. In one possible implementation, the first pad 531 and the second pad 532 are copper pads. The mechanical connection can involve joining pads and raised areas using a soldering process, a sintering process, or a bonding process.

[0073] Fig. Figure 6 illustrates a method for assembling a three-phase inverter with a cooling device according to a possible implementation of the present disclosure. The method 600 includes attaching 610 power modules 611 to a cover 613. Attaching the power modules 611 to the cover 613 may include positioning fastening material 612 between each power module and a raised area of ​​the cover 613. In one possible implementation, the fastening material is a solder paste. In another possible implementation, the top surface of the cover 613 is a copper layer that is silver-plated at least in the areas of the fastening material.

[0074] Method 600 further includes the metered dispensing of an adhesive (e.g., adhesive sealant) into a groove in an upper surface of the body 621 and the bonding 620 of the underside of the cover 613 to the upper surface of the body 621 using the adhesive (e.g., adhesive sealant). In one possible implementation, the bonding includes the application of pressure and heat to the interface between the cover and the body to create a bond (e.g., to cure the adhesive).

[0075] Method 600 can further include fastening 630 the cover to the body using a plurality of screws. Screwing the cover in place can increase the strength of the connection between the cover and the body.

[0076] Fig.Figure 7 is a flowchart of an example method for assembling the three-phase inverter with the cooling device. The method 700 includes attaching a power module 710 to a cover. The cover includes a copper layer on a top surface facing the power module and an aluminum layer on a bottom surface opposite the top surface. The method 700 further includes metering dispensing 720 of adhesive into a groove in an upper surface of a body, the groove surrounding a basin defined by the body, the basin having a lower surface offset by a depth relative to the upper surface. The method 700 further includes bonding 730 the underside of the cover to the upper surface of the body with the adhesive, such that the aluminum layer faces the basin.

[0077] While certain features of the described implementations have been illustrated as described herein, many modifications, substitutions, changes, and equivalents are now apparent to the person skilled in the art. It is therefore understood that the accompanying claims are intended to cover all such modifications and changes that fall within the scope of protection of the implementations. It is understood that they have been presented only as examples, without being limiting, and that various changes to form and details may be made. Each section of the apparatus and / or method described herein may be combined in any combination, except for mutually exclusive combinations. The implementations described herein may include various combinations and / or subcombinations of the functions, components, and / or features of the various described implementations.

[0078] It is understood that in the foregoing description, when an element is described as being switched on, connected, electrically connected, coupled to, or electrically coupled to another element, it may be located directly on, connected to, or coupled to the other element, or one or more elements may be present between them. Conversely, when an element is described as being directly on, directly connected to, or directly coupled to another element, no intermediate elements are present. Although the terms "directly on," "directly connected to," or "directly coupled to" may not be used in the detailed description, elements shown as being "directly on," "directly connected," or "directly coupled" may be identified as such.The claims of the application may be amended, if necessary, to specify exemplary relationships that are described in the patent specification or shown in the figures.

[0079] As used in this patent specification, a singular form may include a plural form unless the context clearly indicates a specific case. Spatial terms (e.g., above, over, upper, under, below, beneath, lower, and the like) are intended to include various orientations of the device in use or operation in addition to the orientation shown in the figures. In some implementations, the relative terms "above" and "below" may each include "vertically above" and "vertically below," respectively. In some implementations, the term "adjacent" may include "laterally adjacent to" or "horizontally adjacent to."

[0080] Some implementations can be realized using various semiconductor processing and / or packaging techniques. Some embodiments can be implemented using different types of semiconductor processing techniques in conjunction with semiconductor substrates, including, but not limited to, silicon (Si), gallium arsenide (GaAs), gallium nitride (GaN), silicon carbide (SiC), and / or the like. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 698,837

[0001]

Claims

[1] Cooling device for a power module, the cooling device comprising: a body, including: a basin with a lower surface that is offset by a depth relative to an upper surface; and a cover that is coupled to the upper surface of the body by an adhesive, the cover including: a first layer of material facing the basin; and a second layer of material facing the power module. [2] Cooling device according to claim 1, further comprising in the upper surface a groove which surrounds at least one section of the basin, wherein the adhesive is arranged in the groove. [3] Cooling device according to claim 2, wherein: The groove is evenly offset to an outer edge of the basin, so that a section of the upper surface is located between the groove and the basin. [4] Cooling device according to claim 2, wherein the groove defines a cross-section which includes: an overflow section that forms a right-angled gap between the first layer of material and the body; and a distribution section that forms a conical space between the first layer of material and the body. [5] Cooling device according to claim 1, wherein the basin and the cover define a reservoir, the reservoir being configured to contain a fluid, the fluid flowing between an inlet opening in the lower surface and an outlet opening in the lower surface. [6] Cooling device according to claim 5, wherein the cover further includes: a multitude of pins extending from the first layer of material into the reservoir. [7] Cooling device according to claim 1, wherein: the first material layer is an aluminum layer; and the second material layer is a copper layer. [8] Cooling device according to claim 7, wherein the aluminium layer is thicker than the copper layer in order to reduce the weight of the cooling device. [9] Cooling device according to claim 7, wherein the copper layer on a surface facing the power module is nickel-plated. [10] Cooling device according to claim 1, wherein the second material layer is a copper layer enclosing a raised area which corresponds in size and shape to a pad on the power module. [11] Cooling device according to claim 10, wherein the raised area is plated with nickel and silver so that the pad of the power module can be soldered or sintered to the raised area. [12] Cooling device according to claim 1, further comprising: at least one fastening element configured to attach the cover to the body. [13] Inverters, including: a first performance module; a second power module; and a cooler coupled to the first power module and the second power module, the cooler including: a body, including: a basin with a lower surface that is offset by a depth relative to an upper surface; and a groove in the upper surface surrounding the basin; and a cover which is glued to the upper surface of the body by means of an adhesive arranged in the groove, the cover enclosing: a first metal layer facing the basin; and a second metal layer facing the first power module and the second power module. [14] Inverter according to claim 13, wherein the basin and the cover define a reservoir configured to contain a fluid flowing between an inlet opening in the lower surface and an outlet opening in the lower surface. [15] Inverter according to claim 14, wherein the first metal layer includes a plurality of pins extending from the first metal layer into the reservoir. [16] Inverter according to claim 13, wherein the groove defines a cross-section which includes: an overflow section that forms a right-angled gap between the first metal layer and the body; and a distribution section that forms a conical space between the first metal layer and the body. [17] Inverter according to claim 13, wherein the first metal layer is an aluminum layer and the second metal layer is a copper layer, the aluminum layer being thicker than the copper layer in order to reduce the weight of the inverter. [18] Procedures, including: Attaching a power module to a copper layer of a cover, wherein the cover encloses the copper layer on a top side facing the power module and an aluminum layer on a bottom side opposite the top side; metered dispensing of adhesive into a groove in an upper surface of a body, wherein the groove surrounds a basin defined by the body, the basin having a lower surface offset by a depth relative to the upper surface; and Adhere the underside of the cover to the upper surface of the body with the adhesive, such that the aluminum layer faces the basin. [19] The method of claim 18, further comprising: Applying pressure and heat over a period of time to clad the copper layer onto the aluminum layer. [20] The method of claim 18, further comprising: Plating the copper layer with one or more other metal layers before attaching the power module.

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