Packaging structure of power module

Abstract

The application discloses a packaging structure of a power module, comprising a DBC substrate, a plurality of semiconductor chips, a plastic package and a liquid cooling radiator. The DBC substrate comprises a first surface and a second surface opposite to each other. The semiconductor chips are arranged on the first surface of the DBC substrate. The plastic package covers the semiconductor chips and at least part of the first surface of the DBC substrate. The liquid cooling radiator surrounds at least one main heat dissipation surface and forms a sealed cavity for the flow of heat dissipation liquid between the liquid cooling radiator and the main heat dissipation surface. The sealed cavity is in communication with an external cooling loop. The packaging structure of the power module provided by the application can make the heat dissipation liquid fully contact the main heat dissipation surface of the power module by surrounding the plurality of surfaces of the power module with the liquid cooling radiator, thereby improving the heat dissipation effect of the power module.

Description

Technical Field

[0001] This utility model relates to the field of power module technology, and in particular to a packaging structure for a power module. Background Technology

[0002] In modern industry, the stable operation of various electronic devices and power systems highly depends on efficient heat dissipation devices. Among them, heat sinks with heat dissipation fins as their core are widely used in aerospace, automotive engineering, electronic communications, and other fields due to their advantages such as simple structure and controllable cost. The heat dissipation efficiency of such heat sinks mainly depends on the contact area between the heat dissipation fins and the air. Generally speaking, the larger the heat dissipation area, the higher the heat exchange rate, and the better it can meet the heat dissipation requirements of high-power equipment.

[0003] However, in many application scenarios, the installation space of the equipment is strictly limited, resulting in insufficient lateral expansion space for the heat sink, making it impossible to increase the heat dissipation area by increasing the lateral arrangement of the fins. To compensate for the insufficient heat dissipation area, the industry generally adopts the method of increasing the height of the heat sink fins, thereby increasing the total heat dissipation area through vertical extension. However, this solution has significant drawbacks: the increase in fin height directly leads to an increase in the overall size of the heat sink, and more importantly, the amount of fin material used increases significantly, resulting in a significant increase in the weight of the heat sink.

[0004] In typical ground equipment or vehicle-mounted scenarios, the increased weight of a radiator may only have a minor impact on the device's portability or energy consumption. However, in the field of aircraft, this issue is dramatically amplified. Aircraft (including drones, helicopters, fixed-wing aircraft, etc.) have extremely stringent requirements regarding the weight of their equipment. Every gram of added weight can lead to a decrease in range, an increase in energy consumption, and even affect flight stability and safety.

[0005] Existing single-sided and / or double-sided heat sinks based on high-fin design, as shown in Figure 1, are too heavy to meet the core requirement of lightweight aircraft, which greatly limits their application in the aerospace field and has become a key technical bottleneck restricting the upgrading of aircraft heat dissipation systems.

[0006] Therefore, how to achieve lightweight design of radiators while ensuring heat dissipation efficiency within limited installation space has become an important issue that the industry urgently needs to address. Utility Model Content

[0007] In view of the above problems, the purpose of this utility model is to provide a packaging structure for a power module. By using a liquid cooler to surround multiple surfaces of the power module, the heat sink can fully contact the main heat dissipation surface of the power module, thereby improving the heat dissipation effect of the power module.

[0008] According to one aspect of the present invention, a power module packaging structure is provided, comprising: a DBC substrate, including a first surface and a second surface facing away from each other, wherein the second surface of the DBC substrate serves as a main heat dissipation surface of the packaging structure; a plurality of semiconductor chips located on the first surface of the DBC substrate; a molding compound covering the semiconductor chips and at least a portion of the first surface of the DBC substrate, wherein the side surface of the molding compound away from the DBC substrate serves as another main heat dissipation surface of the packaging structure, the power module comprising the DBC substrate, the semiconductor chips, and the molding compound; and a liquid cooling radiator surrounding at least one main heat dissipation surface and forming a sealed cavity for the flow of cooling liquid between the liquid and the surrounded main heat dissipation surface, wherein the sealed cavity is connected to an external cooling circuit.

[0009] Optionally, the liquid-cooled heat sink surrounds a portion of the first surface, a portion of the second surface, and two opposing partial side surfaces of the power module, with the first surface and the second surface being disposed opposite to each other.

[0010] Optionally, the liquid-cooled radiator further includes a first pipe and a second pipe, which are respectively connected to the sealed cavity, and serve as the liquid inlet pipe and liquid outlet pipe of the sealed cavity, which are connected to the external cooling circuit.

[0011] Optionally, it further includes: a first finned heat sink, wherein a first surface of the first finned heat sink is connected to a second surface of the DBC substrate.

[0012] Optionally, the second surface of the first finned heat sink includes a fin array located in a sealed cavity formed between the liquid-cooled heat sink and the surface of the power module.

[0013] Optionally, it further includes: a second finned heat sink, the second surface of which is connected to the first surface of the encapsulated body.

[0014] Optionally, the first surface of the second finned heat sink includes a fin array located in a sealed cavity formed between the liquid-cooled heat sink and the surface of the power module.

[0015] Optionally, it further includes: a lead, one end of which is directly or indirectly electrically connected to one of the semiconductor chips, and the other end of which is directly or indirectly electrically connected to another semiconductor chip.

[0016] Optionally, the DBC substrate includes a first metal layer, an insulating layer, and a second metal layer, wherein the second metal layer is a patterned circuit structure, and the semiconductor chip is electrically connected to the second metal layer.

[0017] Optionally, it also includes a lead frame disposed on another opposite side surface of the power module.

[0018] The power module packaging structure provided by this utility model has solder pads located at the edge of the packaging structure, while the central area of ​​the packaging structure is surrounded by a liquid-cooled heat sink. The power module is located in the central area of ​​the packaging structure, and the central area serves as the main heat dissipation area. The liquid-cooled heat sink surrounding the central area allows the heat sink fluid to fully contact the main heat dissipation surface of the power module, thereby improving the heat dissipation effect of the power module. Furthermore, the liquid-cooled heat sink can also reduce the weight of the packaging structure.

[0019] Furthermore, liquid coolers can be used in conjunction with finned heatsinks. Finned heatsinks can increase the heat dissipation surface in the encapsulation structure, while liquid coolers surround part of the surface of the encapsulation structure and the finned heatsink, resulting in better heat dissipation. Attached Figure Description

[0020] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the present invention with reference to the accompanying drawings, in which:

[0021] Figure 1a A bottom view of the packaging structure of a power module is shown;

[0022] Figure 1b It shows along Figure 1a A top view of the packaging structure of a power module, showing a cross-sectional view along line AA;

[0023] Figure 1c A left view of the packaging structure of a power module is shown;

[0024] Figure 2a A cross-sectional view of the packaging structure of a power module according to a first embodiment of the present invention is shown;

[0025] Figure 2b A bottom view of the packaging structure of the power module according to the first embodiment of the present invention is shown, showing a cross-sectional view along line AA.

[0026] Figure 2c A left view of the packaging structure of a power module according to a first embodiment of the present invention is shown;

[0027] Figure 3a A cross-sectional view of the packaging structure of a power module according to a second embodiment of the present invention is shown;

[0028] Figure 3b A bottom view of the packaging structure of the power module according to the second embodiment of the present invention is shown, showing a cross-sectional view along line AA.

[0029] Figure 3cA left view of the packaging structure of a power module according to a second embodiment of the present invention is shown;

[0030] Figure 4a A cross-sectional view of the packaging structure of a power module according to a third embodiment of the present invention is shown;

[0031] Figure 4b A bottom view of the packaging structure of a power module according to a third embodiment of the present invention is shown, showing a cross-sectional view along line AA.

[0032] Figure 4c A left view of the packaging structure of a power module according to a third embodiment of the present invention is shown. Detailed Implementation

[0033] Various embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0034] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples.

[0035] Figure 1a A bottom view of the packaging structure of a power module is shown; Figure 1b It shows along Figure 1a A top view of the packaging structure of a power module, showing a cross-sectional view along line AA; Figure 1c A left view of the packaging structure of a power module is shown.

[0036] refer to Figures 1a to 1c The power module's package structure 100 includes: a finned heat sink 110, a DBC (Direct Bonding Copper) substrate 120 located on the finned heat sink 110, a semiconductor chip 130 located on the DBC substrate 120, a first terminal 141, a lead wire 142, a molding compound 140, and a lead frame 150.

[0037] The finned heat sink 110 includes a first surface and a second surface facing each other. The first surface of the finned heat sink 110 is planar and connected to the DBC substrate 120, so that the heat generated by the semiconductor chip 130 during operation is conducted to the finned heat sink 110 via the DBC substrate 120. The second surface of the finned heat sink 110 includes a plurality of fin arrays 111 extending perpendicular to the second surface. The fin arrays 111 are the core heat dissipation units of the finned heat sink 110, and consist of a plurality of parallel or staggered thin plates (fins), cylinders, or other shaped pillars, distributed vertically or obliquely on the second surface.

[0038] The DBC substrate 120 includes a first metal layer 121, an insulating layer 122, and a second metal layer 123 stacked together. The first metal layer 121 is located on the second surface of the insulating layer 122 and serves to connect the DBC substrate 120 and the finned heat sink 110. The second metal layer 123 is located on the first surface of the insulating layer 122, and the second metal layer 123 is printed to form a circuit structure. The semiconductor chip 130 is located on the DBC substrate 120 and is in contact with the second metal layer 123 on the DBC substrate 120. The DBC substrate 120 serves for the electrical connection of the semiconductor chip 110 and isolates the semiconductor chip 130 from the finned heat sink 110.

[0039] The semiconductor chip 130 includes multiple chips, each connected to a corresponding region of the second metal layer 123 of the DBC substrate 120. Furthermore, different semiconductor chips 130 can be electrically connected via leads 142 and the second metal layer 123, thereby enabling different functions of the power module.

[0040] One end of the first terminal 141 is electrically connected to the semiconductor chip 130 via the second metal layer 123 on the DBC substrate 120, and the other end extends along a third direction and extends above the semiconductor chip 130. In this application, the first direction, the second direction, and the third direction are perpendicular to each other, wherein the first direction is, for example, the horizontal X direction, the second direction is, for example, the horizontal Y direction, and the third direction is, for example, the vertical Z direction.

[0041] The molding compound 140 encapsulates the DBC substrate 120, a portion of the first terminal 141, the lead 142, and the semiconductor chip 130, exposing at least a portion of the first terminal 141.

[0042] The lead frame 150 is located on two opposite side surfaces of the molding compound 140 and can provide a soldering area for the package structure 100 or a fixing structure for the package structure 100.

[0043] In the power module's packaging structure 100, due to the limited heat dissipation area, it is necessary to increase the height of the fin array 111 in the finned heat sink 110 in order to improve the heat dissipation effect. However, the increase in the height of the fin array 111 leads to a significant increase in the weight of the finned heat sink 110.

[0044] Figure 2a A cross-sectional view of the packaging structure of a power module according to a first embodiment of the present invention is shown; Figure 2b A bottom view of the packaging structure of the power module according to the first embodiment of the present invention is shown, showing a cross-sectional view along line AA. Figure 2c A left view of the packaging structure of a power module according to a first embodiment of the present invention is shown.

[0045] refer to Figures 2a to 2c The power module packaging structure 200 of the first embodiment provided in this application includes: a DBC (Direct Bonding Copper) substrate 120, a semiconductor chip 130 located on the DBC substrate 120, leads 142, a molding compound 140, a lead frame 150, and a liquid cooling heat sink 160. The power module includes the DBC substrate 120, the semiconductor chip 130, and the molding compound 140.

[0046] The DBC substrate 120 includes a first surface S21 and a second surface S22 facing away from each other. Specifically, the DBC substrate 120 includes a first metal layer 121, an insulating layer 122, and a second metal layer 123 stacked together. The first metal layer 121 is located on the second surface S32 of the insulating layer 122; the second metal layer 123 is located on the first surface S31 of the insulating layer 122. The second metal layer 123 is printed to form a circuit structure. The semiconductor chip 130 is located on the DBC substrate 120 and is in contact with the second metal layer 123 on the DBC substrate 120. The DBC substrate 120 is used for electrical connection of the semiconductor chip 110 and for downward heat transfer generated by the semiconductor chip 130 during operation.

[0047] The semiconductor chips 130 include multiple chips, each connected to a corresponding region of the second metal layer 123 of the DBC substrate 120. Furthermore, different semiconductor chips 130 can be electrically connected via leads 142 and the second metal layer 123 to achieve different functions of the power module. Specifically, one end of the lead 142 is directly or via the second metal layer 123 on the DBC substrate 120 to one semiconductor chip 130, and the other end is directly or via the second metal layer 123 on the DBC substrate 120 to another semiconductor chip 130, thereby enabling conductive connections between different semiconductor chips 130 via the lead 142 and the second metal layer 123.

[0048] Furthermore, the package structure 200 also includes a plurality of first terminals and / or second terminals. Although not shown in the figures, it is understood that the first and second terminals are used to achieve electrical connections between the package structure 200 and other structures. Specifically, one end of the first terminal is electrically connected to the semiconductor chip 130 via the second metal layer 123 on the DBC substrate 120, and the other end extends along a horizontal second direction and extends to the outside of the DBC substrate 120. One end of the second terminal is electrically connected to the semiconductor chip 130 via the second metal layer 123 on the DBC substrate 120, and the other end extends along a vertical third direction and extends above the semiconductor chip 130. In this application, the first direction, the second direction, and the third direction are mutually perpendicular. Specifically, the first direction is, for example, the horizontal X direction, the second direction is, for example, the horizontal Y direction, and the third direction is, for example, the vertical Z direction.

[0049] The molding compound 140 encapsulates the DBC substrate 120, a portion of the first and / or second terminals, the lead 142, and the semiconductor chip 130, exposing at least a portion of the first and second terminals.

[0050] The first terminal extends along a first or second horizontal direction, thus exposing the side of the first terminal away from the semiconductor chip 130, and the exposed side of the first terminal is located on the side surface of the entire package structure. The second terminal extends along a third vertical direction, thus exposing the side of the second terminal away from the DBC substrate 120, and the exposed side of the second terminal is located on the first surface S41 of the entire package structure 200.

[0051] The lead frame 150 is located on two opposite side surfaces of the molding compound 140, providing a soldering area for the package structure 200 and a fixing structure for the package structure 200. The two opposite side surfaces of the lead frame 150 are, for example, the side surface containing one of the long and wide sides of the first surface S11 of the power module. Specifically, the lead frame 150 also includes a first fixing member 151, a second fixing member 153, and a third fixing member 154, such as... Figure 2a and Figure 2b As shown. The first fixing member 151 is, for example, square and has a through hole 152 in the center. The first fixing member 151 is located, for example, on the side of the encapsulation structure 200. The second fixing member 153 and the third fixing member 154 are located, for example, on the first surface S41 of the encapsulation structure 200. The second fixing member 153 is, for example, a groove, and the third fixing member 154 is, for example, a protrusion. When connected to other structures, any one of the first fixing member 151, the second fixing member 153, and the third fixing member 154 in the lead frame 150 of the encapsulation structure 200 can be fixedly connected to other structures by means of screws, nuts, etc.

[0052] Furthermore, along the second direction, the first surface S11 of the power module can be divided into three regions, including a first region and two second regions, with the first region located between the two second regions, such as... Figure 2a As shown. Along the second direction, the first region is at least a majority of the center of the DBC substrate 120, or the width of the first region in the second direction is greater than the width of the DBC substrate 120 along the second direction, such as... Figure 2a As shown, the projection of the semiconductor chip 130 onto the first surface S11 of the power module falls into the first region. Two second regions are located on either side of the first region, and the projection of the lead frame 150 onto the first surface S11 of the power module falls into the second region. Therefore, the first fixing member 151, the second fixing member 153, and the third fixing member 154 in the lead frame 150 are also located in the second region.

[0053] Furthermore, the portions of the first terminal, second terminal, etc., not surrounded by the encapsulant 140 are also located in the second region.

[0054] The liquid-cooled heat sink 160 surrounds the first region, and also surrounds the first surface S11, the second surface S12, and two opposing side surfaces of the power module within the first region. The first surface S11 and the second surface S12 serve as the two main heat dissipation surfaces of the power module, that is, the two opposing partial side surfaces are the side surfaces where the wide or long side of the main heat dissipation surface is located. The two opposing side surfaces surrounded by the liquid-cooled heat sink 160 are different from the side surface where the lead frame 150 is located; that is, the two side surfaces surrounded by the liquid-cooled heat sink 160 are the side surface where the other of the long and wide sides of the first surface S11 of the power module is located.

[0055] Specifically, the opposite side surface where the lead frame 150 is located is, for example, the side surface where the long side of the first surface S11 of the power module is located, and the opposite side surface surrounded by the liquid cooler 160 is, for example, a portion of the side surface where the wide side of the first surface S11 of the power module is located; or the opposite side surface where the lead frame 150 is located is, for example, the side surface where the long and wide sides of the first surface S11 of the power module are located, and the opposite side surface surrounded by the liquid cooler 160 is, for example, a portion of the side surface where the long side of the first surface S11 of the power module is located.

[0056] The liquid-cooled heat sink 160 is spaced a predetermined distance from the first surface S11, the second surface S12, and a portion of the side surface of the power module to form a sealed cavity. This allows the heat sink to contact the first surface S11 of the power module, the second surface S22 of the DBC substrate 120 (which is also the second surface S12 of the power module), and the opposite side surface where the wide edge of the power module is located through the sealed cavity, thereby achieving heat dissipation. The edge portion of the liquid-cooled heat sink 160 is in close contact with the first surface S11, the second surface S12, and the side surface of the power module, ensuring that the sealed cavity formed between the liquid-cooled heat sink 160 and the power module does not connect to the outside through the surface of the encapsulation structure.

[0057] Furthermore, on the opposite side surface of the power module surrounded by the liquid-cooled radiator 160, a first pipe 161 and a second pipe 162 are respectively included. The first pipe 161 and the second pipe 162 are, for example, an inlet pipe and an outlet pipe, respectively, connected to an external cooling circuit. The heat sink enters the sealed cavity formed between the liquid-cooled radiator 160 and the power module through the first pipe 161 or the second pipe 162, contacts the surface of the power module to remove heat, and then flows out through the second pipe 162 or the first pipe 161, thereby achieving rapid heat dissipation.

[0058] In this embodiment, since the heat sink is in direct contact with the second surface S22 of the DBC substrate 120 and the first surface S11 of the molding compound 140 in the power module, and the heat sink is fluid, rapid heat dissipation can be achieved. Furthermore, since the first and second terminals are located in the second region, they do not affect the external connections of the package structure.

[0059] In this embodiment, multiple first and second surfaces are described, and the accompanying drawings label each first and second surface. For clarity, the various first and second surfaces and their labels are described in detail here, and subsequent embodiments may also use the same reference numerals. Specifically, the DBC substrate 120 has a first surface S21 and a second surface S22; the insulating layer 122 has a first surface S31 and a second surface S32; the power module has a first surface S11 (which is also the first surface of the molding compound 140) and a second surface S12; the packaging structure 200 has a first surface S41 and a second surface S42. Among these, in... Figure 2b In the embodiment shown, the second surface S22 of the DBC substrate 120 is also the second surface S12 of the power module. If the power module has other structures on the second surface of the DBC substrate 120, the surface (second surface) with the other structures facing downwards is used as the second surface S12 of the power module.

[0060] Figure 3a A cross-sectional view of the packaging structure of a power module according to a second embodiment of the present invention is shown; Figure 3b A bottom view of the packaging structure of the power module according to the second embodiment of the present invention is shown, showing a cross-sectional view along line AA. Figure 3c A left view of the packaging structure of a power module according to a second embodiment of the present invention is shown. The difference between the packaging structure 300 of the second embodiment and the first embodiment is that it further includes a first finned heat sink 110. Similarities will not be repeated here; only differences will be described.

[0061] refer to Figures 3a to 3c The power module packaging structure 300 of the second embodiment provided in this application includes: a first fin heat sink 110, a DBC (Direct Bonding Copper) substrate 120, a semiconductor chip 130 located on the DBC substrate 120, leads 142, a molding compound 140, a lead frame 150, and a liquid-cooled heat sink 160. That is, the heat dissipation structure of the second embodiment includes the first fin heat sink 110 and the liquid-cooled heat sink 160. In this embodiment, the power module includes the first fin heat sink 110, the DBC substrate 120, the semiconductor chip 130, and the molding compound 140.

[0062] The first finned heat sink 110 is a passive heat dissipation device that achieves heat transfer by expanding the heat dissipation area, including a first surface S51 and a second surface S52 facing away from each other. The first surface S51 of the finned heat sink 110 is planar and connected to the DBC substrate 120, so that the heat generated by the semiconductor chip 130 during operation is conducted to the finned heat sink 110 via the DBC substrate 120. The second surface S52 of the finned heat sink 110 includes a fin array 111 extending perpendicular to the second surface S52. The fin array 111 is the core heat dissipation unit of the finned heat sink 110, consisting of multiple parallel or staggered thin plates (fins), cylinders, or other shaped pillars, distributed vertically or obliquely on the second surface S52. Through the densely arranged thin plate or pillar structure, the fin array 111 expands the heat dissipation area that originally relied solely on the second surface S52 by several times or even tens of times, greatly improving the contact efficiency with air, thereby improving the heat dissipation effect.

[0063] Furthermore, along the second direction, the first surface S11 of the power module can be divided into three regions, including a first region and two second regions, with the first region located between the two second regions, such as... Figure 3a , Figure 3b As shown. Along the second direction, the first region is at least a portion of the fin array 111 in the first finned heat sink 110, or the width of the first region in the second direction is greater than the width of the fin array 111 in the finned heat sink 110 along the second direction.

[0064] The liquid-cooled heat sink 160 surrounds the first region, and also surrounds the first surface S11, the second surface S12, and two opposing side surfaces of the power module within the first region. The first surface S11 and the second surface S12 serve as the two main heat dissipation surfaces of the power module, i.e., the two opposing partial side surfaces are the side surfaces where the wide or long sides of the main heat dissipation surfaces are located. The liquid-cooled heat sink 160 is spaced a predetermined distance from the surface of the power module to form a sealed cavity, allowing the heat sink to contact the first surface S11 of the power module, the second surface S52 of the first finned heat sink 110, and the opposing partial side surfaces where the wide side of the power module is located through the sealed cavity, thereby achieving heat dissipation. The edge portion of the liquid-cooled heat sink 160 is in close contact with the surfaces of the molding compound 140 and the DBC substrate 120, ensuring that the sealed cavity formed between the liquid-cooled heat sink 160 and the power module does not connect to the outside through the surface of the encapsulation structure.

[0065] In this embodiment, since the heat sink directly contacts the fin array 111 in the first finned heat sink 110 of the power module, and the fin array 111 can significantly increase the surface area, and the heat sink is fluid, the second embodiment can achieve faster heat dissipation compared to the first embodiment. However, compared to the first embodiment, the weight of the heat dissipation structure of the power module packaging structure 300 in the second embodiment will increase.

[0066] Figure 4a A cross-sectional view of the packaging structure of a power module according to a third embodiment of the present invention is shown; Figure 4b A bottom view of the packaging structure of a power module according to a third embodiment of the present invention is shown, showing a cross-sectional view along line AA. Figure 4c A left view of the packaging structure of a power module according to a third embodiment of the present invention is shown. The difference between the packaging structure 400 of the third embodiment and the second embodiment is that it further includes a second finned heat sink 170. Similarities will not be repeated here; only differences will be described.

[0067] refer to Figures 4a to 4c The power module packaging structure 300 of the second embodiment provided in this application includes: a first fin heat sink 110, a DBC (Direct Bonding Copper) substrate 120, a semiconductor chip 130 located on the DBC substrate 120, leads 142, a molding compound 140, a second fin heat sink 170, a lead frame 150, and a liquid-cooled heat sink 160. That is, the heat dissipation structure of the third embodiment includes a first fin heat sink 110, a second fin heat sink 170, and a liquid-cooled heat sink 160. In this embodiment, the power module includes a first fin heat sink 110, a DBC substrate 120, a semiconductor chip 130, a second fin heat sink 170, and a molding compound 140.

[0068] Both the first finned heat sink 110 and the second finned heat sink 170 are passive heat dissipation devices that transfer heat by expanding the heat dissipation area, including a first surface (S51 / S61) and a second surface (S52 / S62) facing away from each other. The first surface S51 of the first finned heat sink 110 is a plane and is connected to the DBC substrate 120, so that the heat generated by the semiconductor chip 130 during operation is conducted to the finned heat sink 110 via the DBC substrate 120. The second surface S62 of the second finned heat sink 170 is a plane and is connected to the side of the molding compound 140 away from the semiconductor chip 130, so that the DBC substrate 120, the semiconductor chip 130, and the molding compound 140 are located between the first surface S51 of the first finned heat sink 110 and the second surface S62 of the second finned heat sink 170.

[0069] The second surface S52 of the first finned heat sink 110 and the first surface S61 of the second finned heat sink 170 include a fin array extending perpendicular to the second surface S62 of the second finned heat sink 170. The fin array is the core heat dissipation unit of the finned heat sink, consisting of multiple parallel or staggered thin plates (fins), cylinders, or other shaped columns, vertically or obliquely distributed on the second surface S52 of the first finned heat sink 110 and the first surface S61 of the second finned heat sink 170. Through the densely arranged thin plates or columnar structure, the fin array expands the heat dissipation area, which originally relied solely on the second surface S52 of the first finned heat sink 110 and the first surface S61 of the second finned heat sink 170, by several times or even tens of times, significantly improving the contact efficiency with air and thus enhancing the heat dissipation effect.

[0070] Furthermore, along the second direction, the first surface S 11 of the power module can be divided into three regions, including a first region and two second regions, with the first region located between the two second regions, such as... Figure 4a , Figure 4b As shown. Along the second direction, the first region is at least a portion of the fin array in the first finned heat sink 110 and / or the second finned heat sink 170, or the width of the first region in the second direction is greater than the width of the fin array in the finned heat sink along the second direction.

[0071] The liquid-cooled heat sink 160 surrounds the first region and encloses a portion of the first surface S11, a portion of the second surface S12, and two opposing partial side surfaces of the power module. The first surface S11 and the second surface S12 serve as the two main heat dissipation surfaces of the power module, i.e., the two opposing partial side surfaces are the side surfaces where the wide or long sides of the main heat dissipation surfaces are located. The liquid-cooled heat sink 160 is spaced a predetermined distance from the main heat dissipation surfaces of the power module to form a sealed cavity, allowing the coolant to contact the first surface S61 of the second finned heat sink 170, the second surface S52 of the first finned heat sink 110, and the opposing partial side surfaces where the wide side of the power module is located through the sealed cavity, thereby achieving heat dissipation. The edge portion of the liquid-cooled heat sink 160 is in close contact with the surfaces of the finned heat sink and the encapsulation, ensuring that the sealed cavity formed between the liquid-cooled heat sink 160 and the power module does not connect to the outside through the surface of the encapsulation structure.

[0072] In this embodiment, since the heat sink directly contacts the fin arrays in the first finned heat sink 110 and the second finned heat sink 170 in the power module, and the fin array can significantly increase the surface area, and the heat sink is fluid, the third embodiment can achieve faster heat dissipation compared to the second embodiment. However, compared to the first and second embodiments, the weight of the heat dissipation structure of the power module packaging structure 400 in the third embodiment will increase.

[0073] The power module packaging structure provided by this utility model has solder pads located at the edge of the packaging structure, while the central area of ​​the packaging structure is surrounded by a liquid-cooled heat sink. The power module is located in the central area of ​​the packaging structure, and the central area serves as the main heat dissipation area. The liquid-cooled heat sink surrounding the central area allows the heat sink fluid to fully contact the main heat dissipation surface of the power module, thereby improving the heat dissipation effect of the power module. Furthermore, the liquid-cooled heat sink can also reduce the weight of the packaging structure.

[0074] Furthermore, liquid coolers can be used in conjunction with finned heatsinks. Finned heatsinks can increase the heat dissipation surface in the encapsulation structure, while liquid coolers surround part of the surface of the encapsulation structure and the finned heatsink, resulting in better heat dissipation.

[0075] As described above, these embodiments of the present invention do not exhaustively cover all details, nor do they limit the invention to the specific embodiments described. Clearly, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to effectively utilize the present invention and its modifications. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A packaging structure for a power module, characterized in that, include: The DBC substrate includes a first surface and a second surface facing away from each other, wherein the second surface of the DBC substrate serves as a main heat dissipation surface of the packaging structure. Multiple semiconductor chips are located on the first surface of the DBC substrate; A molding compound covers at least a portion of the first surface of the semiconductor chip and the DBC substrate, wherein the side of the molding compound away from the DBC substrate serves as another main heat dissipation surface of the packaging structure. A liquid-cooled radiator surrounds at least one main heat dissipation surface and forms a sealed cavity between the surrounded main heat dissipation surface for the flow of heat dissipation liquid, the sealed cavity being connected to an external cooling circuit.

2. The packaging structure according to claim 1, characterized in that, The liquid-cooled heat sink surrounds a portion of the first surface, a portion of the second surface, and two opposing partial side surfaces of the power module. The first surface and the second surface are disposed opposite to each other, and the two opposing partial side surfaces are the side surfaces containing one of the wide side and the long side of the main heat dissipation surface.

3. The packaging structure according to claim 2, characterized in that, The liquid-cooled radiator also includes a first pipe and a second pipe respectively disposed on two opposite side surfaces. The first pipe and the second pipe are connected to the sealed cavity and serve as the liquid inlet pipe and liquid outlet pipe of the sealed cavity, respectively, and are connected to the external cooling circuit.

4. The packaging structure according to claim 3, characterized in that, Also includes: A first finned heat sink, wherein a first surface of the first finned heat sink is connected to a second surface of the DBC substrate.

5. The packaging structure according to claim 4, characterized in that, The second surface of the first finned heat sink includes a fin array located in a sealed cavity formed between the liquid-cooled heat sink and the second surface of the power module.

6. The packaging structure according to claim 3 or 4, characterized in that, Also includes: The second fin heat sink has a second surface connected to the side surface of the molding compound away from the DBC substrate.

7. The packaging structure according to claim 6, characterized in that, The first surface of the second finned heat sink includes a fin array located in a sealed cavity formed between the liquid-cooled heat sink and the first surface of the power module.

8. The packaging structure according to claim 1, characterized in that, Also includes: A lead wire, one end of which is directly or indirectly electrically connected to one of the semiconductor chips, and the other end of which is directly or indirectly electrically connected to another semiconductor chip.

9. The packaging structure according to claim 1, characterized in that, The DBC substrate includes a first metal layer, an insulating layer, and a second metal layer. The second metal layer has a patterned circuit structure, and the semiconductor chip is electrically connected to the second metal layer.

10. The packaging structure according to claim 1, characterized in that, Also includes: The lead frame is disposed on another opposite side surface of the power module, which is the other side surface of the wide side and long side of the main heat dissipation surface.

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