Method for manufacturing a power module and power module

Abstract

This application discloses a method for manufacturing a power module and a power module thereof. The manufacturing method includes: providing a first substrate, the first substrate including three electrically isolated first metal layers; disposing an upper bridge chip assembly on the first metal layers, wherein the upper bridge chip in the upper bridge chip assembly is electrically connected to the first metal layers; providing a second substrate, the second substrate including three electrically isolated second metal layers; disposing a lower bridge chip assembly on the second metal layers, wherein the lower bridge chip in the lower bridge chip assembly is electrically connected to the second metal layers; connecting the upper bridge chip to the second metal layers using a first conductive buffer, and connecting the lower bridge chip to the first metal layers using a second conductive buffer. This application integrates three half-bridge structures into one unit, adopts double-sided packaging, and utilizes conductive buffer blocks to conduct current between the chip and the metal layers, shortening the current conduction distance, reducing stray inductance, and improving heat dissipation. This allows for the manufacture of a power module with simple process, small size, compact structure, and high reliability.

Description

Technical Field

[0001] This application relates to the field of electronic device technology, and more specifically to a method for manufacturing a power module and a power module. Background Technology

[0002] Current power module manufacturing methods often involve placing chips on a substrate to form a bridge arm. To achieve full-bridge functionality, multiple power modules need to be assembled. This results in complex manufacturing processes, a less compact product structure, and a large footprint in applications. Summary of the Invention

[0003] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0004] To at least partially solve the above problems, according to a first aspect of this application, a method for manufacturing a power module is provided, the method comprising the following steps:

[0005] A first substrate is provided, the first substrate comprising three first metal layers electrically isolated from each other;

[0006] An upper bridge chip group is disposed on the first metal layer of the first substrate, and the upper bridge chip in the upper bridge chip group is connected to the first metal layer.

[0007] A second substrate is provided, the second substrate comprising three second metal layers electrically isolated from each other;

[0008] A lower bridge chip group is disposed on the second metal layer of the second substrate, and the lower bridge chip in the lower bridge chip group is connected to the second metal layer;

[0009] The upper bridge chip is connected to the second metal layer using a first conductive buffer, and the lower bridge chip is connected to the first metal layer using a second conductive buffer.

[0010] The manufacturing method of the power module in this application integrates three upper bridge arms and three lower bridge arms into one unit, or in other words, integrates three half-bridge structures into one unit. It adopts double-sided packaging and welds conductive buffer blocks between the chip and the metal layer for current conduction. The conductive buffer blocks are used to conduct current between the chip and the metal layer, replacing the chip wire bonding method in the traditional solution. This shortens the current conduction distance, reduces stray inductance, and improves heat dissipation. It can produce a six-in-one power module product with simple manufacturing process, small size, compact structure and high reliability.

[0011] Optionally, the drain of the upper bridge chip is electrically connected to the first metal layer, and the drain of the lower bridge chip is electrically connected to the second metal layer.

[0012] Optionally, after setting the bridge chip group, the manufacturing method further includes: connecting the source and / or gate of the bridge chip to the first metal layer by wire bonding;

[0013] After setting the lower bridge chip group, the manufacturing method further includes: connecting the source and / or gate of the lower bridge chip to the second metal layer by wire bonding.

[0014] Optionally, the first substrate further includes a third metal layer located on the side of the first substrate opposite to the first metal layer, and the second substrate further includes a fourth metal layer located on the side of the second substrate opposite to the second metal layer. The manufacturing method further includes:

[0015] A first heat dissipation base plate is disposed on the third metal layer;

[0016] A second heat dissipation base plate is provided on the fourth metal layer.

[0017] Optionally, the manufacturing method further includes:

[0018] A first lead frame is provided in the first metal layer, and the first lead frame includes a high-voltage DC terminal and a first control terminal;

[0019] A second lead frame is provided in the second metal layer. The second lead frame includes a high-voltage AC terminal and a second control terminal, wherein the position of the second lead frame is opposite to that of the first lead frame.

[0020] Optionally,

[0021] The high-voltage DC terminal is electrically connected to the first metal layer;

[0022] The high-voltage AC terminal is electrically connected to the second metal layer.

[0023] Optionally, the high-voltage DC terminal includes a positive terminal and a negative terminal, wherein the positive terminal and the negative terminal are stacked.

[0024] Optionally,

[0025] The positive terminal includes a first terminal portion and a second terminal portion connected to each other, and the negative terminal portion is disposed between the first terminal portion and the second terminal portion; or

[0026] The negative terminal includes a first terminal portion and a second terminal portion connected to each other, and the positive terminal is disposed between the first terminal portion and the second terminal portion.

[0027] Optionally, the upper bridge chip and the lower bridge chip are arranged in a staggered manner so that the projection of the upper bridge chip on the first metal layer does not overlap with the projection of the lower bridge chip on the first metal layer.

[0028] Optionally, the manufacturing method further includes:

[0029] The assembled first substrate and second substrate are injection molded to form a plastic encapsulated shell.

[0030] Optionally, the manufacturing method further includes:

[0031] A liquid cooling assembly is provided outside the first heat dissipation base plate and the second heat dissipation base plate, so that the first heat dissipation base plate and the second heat dissipation base plate can be located in the liquid flow channel of the liquid cooling assembly.

[0032] According to a second aspect of this application, a power module is also provided, which is manufactured using the power module manufacturing method described in any of the above-described schemes. Attached Figure Description

[0033] The following drawings, which are incorporated herein by reference and are used to understand this application, illustrate embodiments of the invention and their descriptions to explain the principles of the invention.

[0034] In the attached image:

[0035] Figure 1 This is a three-dimensional structural schematic diagram of a power module according to one embodiment of this application;

[0036] Figure 2 This is a side view schematic diagram of a power module according to one embodiment of this application;

[0037] Figure 3 This is a cross-sectional schematic diagram of a power module according to one embodiment of this application;

[0038] Figure 4 This is a schematic diagram of the connection structure between the upper bridge chip and the first conductive buffer, or a schematic diagram of the connection between the lower bridge chip and the second conductive buffer;

[0039] Figure 5 This is a schematic diagram showing the composition of the first metal layer, the upper bridge chipset, the first control terminal, and the high-voltage DC terminal on the first substrate.

[0040] Figure 6This is a schematic diagram showing the composition of the second metal layer, the lower bridge chipset, and the high-voltage AC terminals on the second substrate.

[0041] Figure 7 This is a side view of the connection structure between the second metal layer and the lower bridge chip group on the second substrate.

[0042] Figure 8 This is a side view of the connection structure between the first metal layer on the first substrate and the upper bridge chipset.

[0043] Figure 9 for Figure 7 A schematic diagram showing the addition of a second conductive buffer element to the middle structure;

[0044] Figure 10 for Figure 8 A schematic diagram showing the addition of the first conductive buffer element to the middle structure;

[0045] Figure 11 for Figure 9 A schematic diagram of the leads from the gate and source of the lower bridge chip to the second metal layer in the middle structure;

[0046] Figure 12 for Figure 10 A schematic diagram of the leads from the gate and source of the upper bridge chip to the first metal layer in the middle structure;

[0047] Figure 13 for Figure 11 A schematic diagram of the first heat dissipation base plate in the middle structure;

[0048] Figure 14 for Figure 12 A schematic diagram showing the second heat dissipation base plate in the middle structure;

[0049] Figure 15 for Figure 13 A schematic diagram showing the first control terminal and the high-voltage DC terminal in the middle structure;

[0050] Figure 16 for Figure 14 A schematic diagram showing the second control terminal and high-voltage AC terminal in the middle structure;

[0051] Figure 17 To be Figure 15 medium structure and Figure 16 A schematic diagram of the interlocking assembly of the central structure;

[0052] Figure 18 This is a cross-sectional front view of a power module according to one embodiment of the present application, in which the liquid cooling assembly is shown;

[0053] Figure 19 This is a schematic cross-sectional view of a power module according to another embodiment of this application, in which a liquid cooling assembly is shown;

[0054] Figure 20 This is a schematic diagram of the structure of the first metal layer, the upper bridge chipset, the first control terminal, and the high-voltage DC terminal on the first substrate according to another embodiment of this application.

[0055] Figure 21 A schematic flowchart of a manufacturing method according to one embodiment of this application; and

[0056] Figure 22 This is a detailed flow diagram of a manufacturing method according to one embodiment of this application;

[0057] Explanation of reference numerals in the attached figures:

[0058] 100: Power Module; 111: First Metal Layer

[0059] 112: Upper bridge chip; 113: First conductive buffer.

[0060] 114: High-voltage DC terminal; 115: Third metal layer

[0061] 116: First heat sink base plate; 117: First lead wire connection area

[0062] 118: First Link Area 119: Second Link Area

[0063] 121: First control terminal; 122: First insulating layer

[0064] 123: First lead; 124: First connecting layer

[0065] 125: Third Connector Layer 126: Fifth Connector Layer

[0066] 127 / 227: Positive terminal 127a: First terminal

[0067] 127b: Second terminal section; 127c / 227c: Positive pin

[0068] 128 / 228: Negative terminal 128c / 228c: Negative pin

[0069] 228a: First terminal section; 228b: Second terminal section

[0070] 131: Second metal layer; 132: Lower bridge chip

[0071] 133: Second conductive buffer component; 134: High-voltage AC terminal

[0072] 135: Fourth metal layer; 136: Second heat dissipation base plate

[0073] 137: Second Lead Link Area 138: Second Lead

[0074] 139: Second insulating layer; 141: Second control terminal

[0075] 142: Second Connector Layer 143: Fourth Connector Layer

[0076] 144: Sixth connecting layer; 150: Liquid cooling assembly

[0077] 151: Liquid inlet section; 152: Liquid outlet section

[0078] 153: First flow channel section 154: Second flow channel section

[0079] 155: First liquid flow channel; 156: Second liquid flow channel

[0080] 157: First Channel 158: Second Channel

[0081] 159: Third Channel 161: Fourth Channel

[0082] 120: End cap plate; 170: Plastic encapsulated housing Detailed Implementation

[0083] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0084] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof.

[0085] The ordinal numbers such as “first” and “second” used in this application are merely identifiers and have no other meaning, such as a specific order. Furthermore, for example, the term “first component” does not imply the existence of a “second component,” and the term “second component” does not imply the existence of a “first component.” It should be noted that the terms “upper,” “lower,” “front,” “back,” “left,” “right,” “inner,” “outer,” and similar expressions used herein are for illustrative purposes only and are not intended to be limiting.

[0086] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings.

[0087] Figures 1 to 19 The diagram shows a power module product manufactured according to a power module manufacturing method of one embodiment of this application, and schematic diagrams of partial process products corresponding to different steps. Figure 20 A partial schematic diagram of a power module product manufactured according to a power module manufacturing method of another embodiment of this application is shown. Figure 21 A schematic flowchart of a method for manufacturing a power module according to one embodiment of this application is shown. Figure 22 A detailed flowchart illustrating a method for manufacturing a power module according to one embodiment of this application is shown.

[0088] In one implementation, such as Figure 21 As shown, this application provides a method for manufacturing a power module, the method comprising:

[0089] A first substrate is provided, the first substrate including three first metal layers 111 electrically isolated from each other;

[0090] An upper bridge chip group is disposed on the first metal layer 111 of the first substrate, and the upper bridge chip 112 in the upper bridge chip group is connected to the first metal layer 111.

[0091] A second substrate is provided, the second substrate including three second metal layers 131 electrically isolated from each other;

[0092] A lower bridge chip group is disposed on the second metal layer 131 of the second substrate, and the lower bridge chip 132 in the lower bridge chip group is connected to the second metal layer 131.

[0093] The upper bridge chip 112 is connected to the second metal layer 131 by the first conductive buffer 113, and the lower bridge chip 132 is connected to the first metal layer 111 by the second conductive buffer 133.

[0094] The manufacturing method of the power module in this application integrates three upper bridge arms and three lower bridge arms into one unit, or in other words, integrates three half-bridge structures into one unit. It adopts double-sided packaging and welds conductive buffer blocks between the chip and the metal layer for current conduction. The conductive buffer blocks are used to conduct current between the chip and the metal layer, replacing the chip wire bonding method in the traditional solution. This shortens the current conduction distance, reduces stray inductance, and improves heat dissipation. It can produce a six-in-one power module product with simple manufacturing process, small size, compact structure and high reliability.

[0095] The drain of the upper bridge chip 112 is electrically connected to the first metal layer 111, and the drain of the lower bridge chip 132 is electrically connected to the second metal layer 131. By setting the drains of the chips to different orientations, heat is dissipated through the first substrate and the second substrate respectively, resulting in better heat dissipation.

[0096] Figure 22 A detailed flowchart illustrating the manufacturing method of the power module according to this embodiment is shown below, and will be described in detail below. It should be noted that... Figure 22 This diagram only schematically illustrates a detailed process flow of the manufacturing method of the power module according to this embodiment; the order of the steps can be adjusted as feasible. The power module 100 can be a three-phase full-bridge structure. In this embodiment, a three-phase full-bridge power module 100 is used as an example.

[0097] It should be noted that this power module can be placed horizontally, upside down, or in any orientation during operation to suit the needs of the work environment.

[0098] like Figures 1 to 10 As shown, the power module is placed horizontally, with a second substrate stacked on top of the first substrate. For example, they can be arranged vertically and horizontally, with some spacing between them. The first substrate includes a first metal layer 111, a first insulating layer 122, and a third metal layer 115 stacked sequentially. The third metal layer 115 is located on the side of the first substrate opposite to the first metal layer 111; in other words, the first metal layer 111 and the third metal layer 115 are respectively disposed on the upper and lower surfaces of the first insulating layer 122. The second substrate includes a second metal layer 131, a second insulating layer 139, and a fourth metal layer 135 stacked sequentially. The fourth metal layer 135 is located on the side of the first substrate opposite to the second metal layer 131; in other words, the fourth metal layer 135 and the second metal layer 131 are respectively disposed on the upper and lower surfaces of the second insulating layer 139. The second insulating layer 139 is arranged vertically and horizontally, with some spacing between it and the first insulating layer 122, and the second insulating layer 139 is disposed above the first insulating layer 122. Copper is preferably used for the aforementioned metal layers because copper has good heat dissipation performance and high electrical conductivity. The thickness of both the metal layer and the insulating layer can be flexibly selected according to the usage requirements and actual production conditions.

[0099] The first metal layer 111 can also be processed with at least one rounded edge, which can reduce current loss due to the path and increase current carrying capacity. The number of rounded edges can be flexibly selected according to the actual working conditions.

[0100] The first insulating layer 122 and the second insulating layer 139 are preferably made of ceramic materials, and can be selected from materials such as silicon nitride, alumina, and aluminum nitride. Considering the coefficient of thermal expansion and thermal conductivity, silicon nitride is more preferred. Three first metal layers 111 are spaced apart on the first insulating layer 122, thereby electrically isolating each other on the first insulating layer 122. Three second metal layers 131 are spaced apart on the second insulating layer 139, thereby electrically isolating each other on the second insulating layer 139. An upper bridge chip assembly is disposed on the first metal layer 111, and the drain of the upper bridge chip 112 in the upper bridge chip assembly is connected to the first metal layer 111. A lower bridge chip assembly is disposed on the second metal layer 131, and the drain of the lower bridge chip 132 in the lower bridge chip assembly is connected to the second metal layer 131. A first conductive buffer 113 connects the upper bridge chip 112 to the second metal layer 131, and a second conductive buffer 133 connects the lower bridge chip 132 to the first metal layer 111. Specifically, the first conductive buffer 113 is disposed on the upper bridge chip 112 by, for example, soldering and connected to the second metal layer 131 by, for example, soldering. The second conductive buffer 133 is disposed on the lower bridge chip 132 by, for example, soldering and connected to the first metal layer 111 by, for example, soldering. The upper bridge chip 112 is electrically connected to the first metal layer 111, the lower end of the first conductive buffer 113 is electrically connected to the upper bridge chip 112, and the upper end of the first conductive buffer 113 is electrically connected to the second metal layer 131. The first metal layer 111 and the second metal layer 131 are etched and processed to form electrical circuits that can connect the drain, source, and gate of the chip, realizing the electrical circuit connection of the chip. The first insulating layer 122 and the second insulating layer 139 have good insulation properties, which can realize the electrical isolation between the first metal layer 111 and the third metal layer 115, and the electrical isolation between the second metal layer 131 and the fourth metal layer 135, and can also serve as the substrate for the upper bridge chip 112 and the lower bridge chip 132, reducing the thermal deformation of the chip and the metal layers.

[0101] The upper bridge chip 112 and the lower bridge chip 132 can be selected from silicon carbide-based field-effect transistors, silicon-based insulated-gate bipolar transistors (IGBTs), and diodes, and are preferably silicon carbide chips. The upper bridge chip 112 has a metal plating layer on its surface facing the first metal layer 111, its surface facing the first conductive buffer 113, and its surface used for wire bonding. The lower bridge chip 132 also has a metal plating layer on its surface facing the second metal layer 131, its surface facing the second conductive buffer 133, and its surface used for wire bonding. The purpose of this metal plating layer is to better fuse with the solder, thereby achieving welding between different components. The material and thickness of the metal plating layer are not limited and can be flexibly selected according to usage requirements and actual production conditions.

[0102] In actual production, the first and second substrates can be copper-clad ceramic (DBC) boards and AMB boards, with AMB boards being more preferred. From this perspective, the two AMB boards are arranged opposite each other. Figures 1-3 Taking a horizontally placed power module as an example, the upper bridge chip 112 is electrically connected to the upper AMB board through the first conductive buffer 113, and the lower bridge chip 132 is electrically connected to the lower AMB board through the second conductive buffer 133.

[0103] In the manufacturing process of this embodiment, multiple soldering steps are employed. For example, soldering is performed between the upper bridge chip 112 and the first metal layer 111 to form a first connection layer 124. In other words, the upper bridge chip 112 and the first metal layer 111 are electrically connected through the first connection layer 124. Similarly, soldering is performed between the first conductive buffer 113 and the upper bridge chip 112 to form a third connection layer 125, thereby achieving an electrical connection. Soldering is performed between the first conductive buffer 113 and the second metal layer 131 to form a fifth connection layer 126, thereby achieving an electrical connection. Soldering is performed between the lower bridge chip 132 and the second metal layer 131 to form a second connection layer 142. In other words, the lower bridge chip 132 and the second metal layer 131 are electrically connected through the second connection layer 142. Soldering is performed between the second conductive buffer 133 and the lower bridge chip 132 to form a fourth connection layer 143, thereby achieving an electrical connection. A sixth connection layer 144 is formed by soldering the second conductive buffer 133 to the first metal layer 111, thereby achieving electrical connection. The first conductive buffer 113 and the second conductive buffer 133 reduce the welding stress on the copper-clad ceramic substrate and reduce thermal deformation of the material module. Furthermore, both the first conductive buffer 113 and the second conductive buffer 133 have a certain height, providing space for bonding low-voltage leads. The first conductive buffer 113 and / or the second conductive buffer 133 can be metals or metal alloys such as copper, molybdenum, silver, and nickel, preferably molybdenum or copper. Both the surface of the first conductive buffer 113 and / or the surface of the second conductive buffer 133 facing the chip and the surface facing the substrate have metal plating. The material and thickness of the metal plating are not limited and can be flexibly selected according to usage requirements and actual production conditions. All connection layers in this invention are solder layers, which can be formed by reflow soldering with lead-containing or lead-free solder, or by solder paste or metal sintering (e.g., silver sintering or copper sintering).

[0104] Optionally, after setting the upper bridge chipset, the manufacturing method of this embodiment further includes: bonding the source and / or gate of the upper bridge chip 112 to the first metal layer 111 via wire bonding; after setting the lower bridge chipset, the manufacturing method of this embodiment further includes: bonding the source and / or gate of the lower bridge chip 132 to the second metal layer 131 via wire bonding.

[0105] like Figures 11-17 As shown, the gate or source of the upper bridge chip 112 is electrically connected to the first metal layer 111 by wire bonding, that is, a first lead 123 is led out from the gate or source of the upper bridge chip 112 to the first metal layer 111. The gate or source of the lower bridge chip 132 is electrically connected to the second metal layer 131 by wire bonding, that is, a second lead 138 is led out from the gate or source of the lower bridge chip 132 to the second metal layer 131. This enables chip control and / or voltage sampling. Equal gate sampling spacing and equal source sampling spacing effectively reduce wiring paths, shorten wire length, and reduce parasitic inductance and capacitance during module operation. The wire connection surfaces of the gate and source of the upper bridge chip 112 are disposed on the first metal layer 111. Figure 5 The two leftmost first control terminals 121 are led out for control and / or sampling. The gate and source lead connection surfaces of the lower bridge chip 132 are disposed on the second metal layer 131, and can be led out by the second control terminal 141 for control and / or sampling. The height of the lead must not exceed the height of the first conductive buffer 113 and the second conductive buffer 133. To reduce the lead height, a jumper structure is fabricated on the left side of the chip gate connection area. The jumper structure can be used as an intermediate connection structure for the lead, dividing one lead into two, which can effectively reduce the lead height and thus reduce the impact on the height of the first conductive buffer 113 and the second conductive buffer 133. The first lead 123 and the second lead 138 must not have any cross interference to avoid short circuits and other situations.

[0106] The manufacturing method of this embodiment further includes, for example, welding a first heat dissipation base plate 116 onto the third metal layer 115, and, for example, welding a second heat dissipation base plate 136 onto the fourth metal layer 135. Figure 1 , Figure 2 and Figures 13-19 As shown, the power module 100 according to this application may further include a first heat dissipation base plate 116 and a second heat dissipation base plate 136, respectively disposed on the third metal layer 115 and the fourth metal layer 135. The first heat dissipation base plate 116 and the second heat dissipation base plate 136 are preferably welded to the third metal layer 115 and the fourth metal layer 135, respectively. The first heat dissipation base plate 116 and the second heat dissipation base plate 136 are preferably formed from aluminum or its alloy through processing. The heat dissipation form of the first heat dissipation base plate 116 and the second heat dissipation base plate 136 is not limited; it may include heat dissipation pins, heat dissipation fins, or other reasonable heat dissipation base plate forms selected according to actual conditions. The length and diameter of the heat dissipation pins can also be flexibly selected according to actual needs and usage conditions; the diameter can vary and is not strictly defined.

[0107] The manufacturing method of this embodiment may further include providing a first lead frame on a first metal layer 111, the first lead frame including a high-voltage DC terminal 114 and a first control terminal 121; and providing a second lead frame on a second metal layer 131, the second lead frame including a high-voltage AC terminal 134 and a second control terminal 141, such that the position of the second lead frame is opposite to that of the first lead frame. The first control terminal 121 and the second control terminal 141 can be coupled to a control signal and / or a sampling signal.

[0108] High-voltage AC terminals 134 are disposed on and electrically connected to the second metal layer 131. There are three high-voltage AC terminals 134, which are connected to the three-phase lines of the motor, thereby enabling three-phase control of the motor through the power module 100 of this invention. The drain of the upper bridge chip 112 is electrically connected to the high-voltage AC terminals 134 through the first metal layer 111.

[0109] The first metal layer 111 of the first substrate includes a first link region 118 and a second link region 119. The upper bridge chip is disposed in the first link region 118, and the first link region 118 is insulated from the second link region 119. A high-voltage DC terminal 114 is disposed on the first metal layer 111 and electrically connected to it. The high-voltage DC terminal 114 includes a positive terminal 127 and a negative terminal 128. The positive terminal 127 is connected to the first link region 118, and the negative terminal 128 is connected to the second link region 119. The positive terminal 127 and the negative terminal 128 are stacked. This stacked design allows the positive terminal 127 and the negative terminal 128 to generate currents in opposite directions. Due to electromagnetic coupling, stray inductance at the terminals is reduced, improving the reliability of the power module 100. Figure 5 and Figure 6As shown, optionally, the positive terminal 127 includes a first terminal portion 127a and a second terminal portion 127b connected to each other, and the negative terminal 128 is disposed between the first terminal portion 127a and the second terminal portion 127b. It is understood that, if desired, the positive terminal 127 may also have only one terminal portion or multiple terminal portions. The positive terminal 127 and the negative terminal 128 of the power module 100 preferably have no through holes, and can be stacked and connected using a laser welding process, simplifying the process flow. Optionally, the positive terminal 127 includes at least two positive pins 127c, and the negative terminal 128 includes at least two negative pins 128c, with the at least two positive pins 127c symmetrically arranged on both sides of the at least two negative pins 128c. Preferably, the positive terminal 127 has 4 positive pins 127c, the negative terminal 128 has 4 negative pins 128c, the first terminal portion 127a and the second terminal portion 127b each have 2 positive pins 127c, and the 4 negative pins 128c are arranged in the center, that is, there are 2 positive pins 127c on each side of the 4 negative pins 128c.

[0110] The positive terminal 127 can be connected to the positive terminal of the capacitor in the motor controller, and the negative terminal 128 is connected to the negative terminal of the capacitor. Current flows through the positive terminal 127 of the high-voltage DC terminal 114 into the first link region 118 of the first metal layer 111, through the drain of the upper bridge chip 112, and through the source of the upper bridge chip 112. It then flows through the first conductive buffer 113, which is connected to the second metal layer 131, and through the second metal layer 131 to the high-voltage AC terminal 134. Reverse current flows through the high-voltage AC terminal 134 into the three second metal layers 131, through the drain of the lower bridge chip 132, through the lower bridge chip 132, into the source of the lower bridge chip 132, through the second conductive buffer 133, into the second link region 119 of the first metal layer 111, and out through the negative terminal 128 of the high-voltage DC terminal 114.

[0111] The high-voltage DC terminal 114, high-voltage AC terminal 134, and control terminal in this application are all made of copper or its alloy through processing.

[0112] In the manufacturing method of this embodiment, the upper and lower components of the double-sided structure can be assembled using a positioning fixture. In this power module, the upper bridge chip 112 and the lower bridge chip 132 are staggered so that the projection of the upper bridge chip 112 onto the first metal layer 111 does not overlap with the projection of the lower bridge chip 132 onto the first metal layer 111. This increases the heat dissipation of the power module 100. The first insulating layer 122 is provided with the gate resistor of the upper bridge chip and the first lead connection area 117, and the second insulating layer 139 is provided with the gate resistor of the lower bridge chip and the second lead connection area 137. The high-voltage DC terminal 114 is partially led out from the first lead connection area 117, and the high-voltage AC terminal 134 is connected to the second lead connection area 137. The upper bridge chip group includes at least two upper bridge chips 112, preferably arranged symmetrically with respect to the first lead connection area 117; the lower bridge chip group includes at least two lower bridge chips 132, preferably arranged symmetrically with respect to the second lead connection area 137. The symmetrical arrangement of the upper bridge chip 112 and the lower bridge chip 132 enables uniform current flow and balanced heat dissipation. More preferably, the upper bridge chip group includes six upper bridge chips 112, arranged in a 2*3 array and symmetrically positioned relative to the first lead connection area 117, meaning there are three upper bridge chips 112 spaced apart on each side of the first lead connection area 117. The lower bridge chip group includes six lower bridge chips 132, arranged in a 2*3 array and symmetrically positioned relative to the second lead connection area 137, meaning there are three upper bridge chips 112 spaced apart on each side of the second lead connection area 137.

[0113] The manufacturing method of this embodiment may further include injection molding the assembled first and second substrates to form a plastic-encapsulated housing 170. Plastic encapsulation typically uses materials such as epoxy resin to integrally encapsulate the module, simplifying the process and reducing complexity. The plastic-encapsulated housing 170 produced by this injection molding process is heat-resistant and highly reliable. After this step, the first substrate, second substrate, and three half-bridge structures of the power module 100 are housed within the accommodating space of the plastic-encapsulated housing 170. The plastic-encapsulated housing 170 completely encapsulates the aforementioned components except for the first heat sink 116 and the second heat sink 136. Heat sink pins or heat sink fins may protrude from the plastic-encapsulated housing 170. The gap between the circuit module (e.g., chip, conductive buffer, lead, power terminal, and control terminal) and the first and second substrates is electrically isolated by the epoxy encapsulation.

[0114] The manufacturing method of this embodiment may further include providing a liquid cooling assembly 150 outside the first heat dissipation base plate and the second heat dissipation base plate, such that the first heat dissipation base plate 116 and the second heat dissipation base plate 136 are located in the liquid flow channel of the liquid cooling assembly 150. Figures 17-18 and Figure 22As shown, after the above steps, the power module 100 includes a liquid cooling assembly 150, which uses direct cooling on both the top and bottom surfaces to dissipate heat. This effectively reduces the thermal resistance of the chip, improves the uniformity of chip heat dissipation, solves the problem of excessive junction temperature in the power module of pure electric vehicles, and effectively reduces the module size. The liquid cooling assembly 150 includes a liquid inlet 151, a liquid outlet 152, a first flow channel 153, and a second flow channel 154. The liquid inlet 151 is located at one end of the power module 100. The liquid outlet 152 is located at the other end of the power module 100. The first flow channel 153 connects the liquid inlet 151 and the liquid outlet 152. The first flow channel 153 is disposed on the first substrate, specifically on the third metal layer 115. A first liquid flow channel 155 is formed between the first flow channel 153 and the first substrate, and a first heat dissipation base plate 116 is located in the first liquid flow channel 155. The second flow channel 154 is disposed on the second substrate, specifically on the fourth metal layer 135. A second liquid flow channel 156 is formed between the second flow channel 154 and the second substrate, and the second heat dissipation base plate 136 is located in the second liquid flow channel 156. The first heat dissipation base plate 116 and the second heat dissipation base plate 136 can be respectively installed in the first liquid flow channel 155 and the second liquid flow channel 156. Coolant, such as water, flows through the heat dissipation pins and / or heat dissipation fins of the first heat dissipation base plate 116 and the second heat dissipation base plate 136 for convection heat dissipation. Optionally, the liquid inlet 151 is provided with a first channel 157 and a second channel 158, wherein the first channel 157 communicates with the first liquid flow channel 155 and the second channel 158 communicates with the second liquid flow channel 156; the liquid outlet 152 is provided with a third channel 159 and a fourth channel 161, wherein the third channel 159 communicates with the first liquid flow channel 155 and the fourth channel 161 communicates with the second liquid flow channel 156.

[0115] The liquid cooling assembly 150 can be configured such that the coolant flows in from one side and flows out from the other. For example, the coolant can enter from the inlet 151, split into the first liquid flow channel 155 and the second liquid flow channel 156 through the first channel 157 and the second channel 158 respectively, flow on the first heat dissipation base plate 116 and the second heat dissipation base plate 136 respectively, and then flow out through the third channel 159 and the fourth channel 161 respectively, and then flow out after merging at the outlet 152.

[0116] The liquid cooling assembly 150 can also be configured such that coolant flows in from one side and out from the same side. In this case, the second channel 158 and the third channel 159 are connected. The liquid cooling assembly 150 also includes an end cover plate 120, which is disposed at the end of the liquid outlet 152 to close the fourth channel 161 and the third channel 159. For example, coolant can enter the second liquid flow channel 156 from the second channel 158, flow out from the fourth channel 161 after passing through the second heat dissipation base plate 136, then flow in from the third channel 159, enter the first liquid flow channel 155, and flow out from the first channel 157 after passing through the first heat dissipation base plate 116.

[0117] Optionally, the first flow channel portion 153 is sealed to the edge of the first heat dissipation base plate 116, and the second flow channel portion 154 is sealed to the edge of the second heat dissipation base plate 136; or the first flow channel portion 153 and the first heat dissipation base plate 116 are constructed as an integral component, and the second flow channel portion 154 and the second heat dissipation base plate 136 are constructed as an integral component. Understandably, the above structure can prevent coolant from entering the circuit module.

[0118] In this invention, components such as flow channels and channels in the first heat dissipation base plate 116, the second heat dissipation base plate 136, and the liquid cooling assembly 150 are formed by processing aluminum or its alloys, and the specific form of flow channels and channels is not limited in any way.

[0119] In other embodiments, the negative terminal 228 includes a first terminal portion 228a and a second terminal portion 228b connected to each other, and the positive terminal 227 is disposed between the first terminal portion 228a and the second terminal portion 228b. It is understood that, if desired, the negative terminal 228 may also have only one terminal portion or multiple terminal portions. Figure 20 As shown, the positive terminal 227 includes at least two positive pins 227c, and the negative terminal 228 includes at least two negative pins 228c. The at least two positive pins 227c are symmetrically arranged on both sides of the at least two negative pins 228c. The positive terminal 227 has four positive pins 227c, and the negative terminal 228 has four negative pins 228c. The first terminal portion 228a and the second terminal portion 228b each have two negative pins 228c. The four negative pins 228c are centrally arranged, meaning there are two positive pins 227c on each side of the four negative pins 228c. In this case, the negative terminal 228 is connected to the first connection area, and the positive terminal 227 is connected to the second connection area. The remaining parts not described in this embodiment refer to the description and figures in the above embodiments, and for the sake of brevity, they will not be described in detail and / or illustrated further.

[0120] In embodiments not shown, the positive terminal includes at least two positive pins, and the negative terminal includes at least two negative pins. The at least two negative pins are symmetrically arranged on both sides of the at least two positive pins. The remaining parts not described refer to the description and / or illustrations in the above embodiments.

[0121] This application also provides a power module manufactured using the manufacturing method of the above embodiments. The structure of the power module can be referred to the relevant description of the manufacturing method embodiments described above, and will not be repeated here.

[0122] The processes and steps described in all the preferred embodiments above are merely examples. Unless adverse effects occur, various processing operations can be performed in a different order than those described above. For example, the soldering order between the chip, conductive buffer, and metal layer can be flexibly adjusted according to actual operating conditions. Similarly, the soldering order of the high-voltage AC terminals, high-voltage DC terminals, and control terminals to the metal layer can be flexibly adjusted according to actual operating conditions. For instance, the wire bonding order of the first and second leads, as well as the aforementioned soldering order, can all be flexibly adjusted according to actual operating conditions, provided they are feasible. The order of the steps in the above process can also be added, combined, or deleted according to actual needs.

[0123] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for descriptive purposes only and is not intended to limit the scope of this application. Features described in one embodiment may be applied, alone or in combination with other features, to another embodiment, unless that feature is not applicable in that other embodiment or is otherwise stated.

[0124] This application has been described through the above embodiments. However, it should be understood that the above embodiments are only for illustrative purposes. This application is not limited to the above embodiments. Many variations and modifications can be made based on the teachings of this application, and all such variations and modifications fall within the scope of protection claimed in this application.

Claims

1. A method for manufacturing a power module, characterized in that, The manufacturing method includes the following steps: A first substrate is provided, the first substrate comprising three first metal layers electrically isolated from each other; An upper bridge chip group is disposed on each of the first metal layers of the first substrate, and the upper bridge chip in the upper bridge chip group is connected to the first metal layer. A second substrate is provided, the second substrate comprising three second metal layers electrically isolated from each other; A lower bridge chip group is disposed on each of the second metal layers of the second substrate, and the lower bridge chip in the lower bridge chip group is connected to the second metal layer; The upper bridge chip is connected to the second metal layer using a first conductive buffer, and the lower bridge chip is connected to the first metal layer using a second conductive buffer. After setting the bridge chip group, the manufacturing method further includes: connecting the source and / or gate of the bridge chip to the first metal layer therethrough by wire bonding; After setting the lower bridge chip group, the manufacturing method further includes: connecting the source and / or gate of the lower bridge chip to the second metal layer therethrough by wire bonding.

2. The method for manufacturing a power module according to claim 1, characterized in that, The drain of the upper bridge chip is electrically connected to the first metal layer, and the drain of the lower bridge chip is electrically connected to the second metal layer.

3. The method for manufacturing a power module according to claim 1, characterized in that, The first substrate further includes a third metal layer located on the side of the first substrate opposite to the first metal layer, and the second substrate further includes a fourth metal layer located on the side of the second substrate opposite to the second metal layer. The manufacturing method further includes: A first heat dissipation base plate is disposed on the third metal layer; A second heat dissipation base plate is provided on the fourth metal layer.

4. The method for manufacturing a power module according to any one of claims 1-3, characterized in that, The manufacturing method further includes: A first lead frame is provided in the first metal layer, and the first lead frame includes a high-voltage DC terminal and a first control terminal; A second lead frame is provided in the second metal layer. The second lead frame includes a high-voltage AC terminal and a second control terminal, wherein the position of the second lead frame is opposite to that of the first lead frame.

5. The method for manufacturing a power module according to claim 4, characterized in that, The high-voltage DC terminal is electrically connected to the first metal layer; the high-voltage AC terminal is electrically connected to the second metal layer.

6. The method for manufacturing a power module according to claim 5, characterized in that, The high-voltage DC terminal includes a positive terminal and a negative terminal, which are stacked together.

7. The method for manufacturing a power module according to claim 6, characterized in that, The positive terminal includes a first terminal portion and a second terminal portion connected to each other, and the negative terminal portion is disposed between the first terminal portion and the second terminal portion; or The negative terminal includes a first terminal portion and a second terminal portion connected to each other, and the positive terminal is disposed between the first terminal portion and the second terminal portion.

8. The method for manufacturing a power module according to claim 1, characterized in that, The upper bridge chip and the lower bridge chip are staggered so that the projection of the upper bridge chip on the first metal layer does not overlap with the projection of the lower bridge chip on the first metal layer.

9. The method for manufacturing a power module according to claim 3, characterized in that, The manufacturing method further includes: injection molding the assembled first substrate and second substrate to form a plastic encapsulated shell.

10. The method for manufacturing a power module according to claim 9, characterized in that, The manufacturing method further includes: providing a liquid cooling component outside the first heat dissipation base plate and the second heat dissipation base plate, so that the first heat dissipation base plate and the second heat dissipation base plate can be located in the liquid flow channel of the liquid cooling component.

11. A power module, characterized in that, The power module is manufactured using the manufacturing method described in any one of claims 1-10.

Images