Power module and power device

Abstract

The utility model provides a power module and power equipment, and belongs to the technical field of heat dissipation. The power module comprises a first copper-clad plate, a second copper-clad plate, m power chips and a strip clip; the m power chips and the clip are located between the first copper-clad plate and the second copper-clad plate, and m is an integer greater than or equal to 1; and each power chip is electrically connected with the first copper-clad plate or the second copper-clad plate through the clip. According to the power module, the m power chips are located between the first copper-clad plate and the second copper-clad plate, double-face heat dissipation is adopted for the power chips, and the heat dissipation capacity of the power module can be improved. And the clip is arranged between the first copper-clad plate and the second copper-clad plate, and the area of the clip is large, so that the heat of the power chip can be quickly transferred to the copper-clad plates, and the heat dissipation capability of the power module is further improved.

Description

Technical Field

[0001] The present disclosure relates to the field of heat dissipation technology, and in particular to a power module and a power device. Background Art

[0002] As the power of power modules, such as insulated gate bipolar transistor (IGBT) modules, silicon carbide SiC modules, and power modules, increases, the heat dissipation capacity required by power modules is also increasing. However, the heat dissipation capacity of current power modules is a bottleneck that restricts further increase in power. Utility Model Content

[0003] The present disclosure provides a power module and a power device, wherein the power module includes two copper-clad boards, and a plurality of power chips are located between the two copper-clad boards. This solution of adopting double-sided heat dissipation for the power chips can improve the heat dissipation capacity of the power module. In addition, clips (strips) are arranged between the plurality of power chips and the copper-clad boards instead of spacers (gaskets). The area of ​​the clips is relatively large, and the heat of the power chips can be quickly transferred to the copper-clad boards, further improving the heat dissipation capacity of the power module.

[0004] In a first aspect, the present disclosure provides a power module, the power module comprising a first copper clad laminate, a second copper clad laminate, m power chips and a strip clip;

[0005] The m power chips and the clip are both located between the first copper clad laminate and the second copper clad laminate, and m is an integer greater than or equal to 1;

[0006] Each power chip is electrically connected to the first copper clad laminate or the second copper clad laminate through the clip.

[0007] In the solution disclosed in the present disclosure, the power module includes two copper-clad boards, a first copper-clad board and a second copper-clad board, and multiple power chips are located between the two copper-clad boards. Both copper-clad boards are used to dissipate heat for multiple power chips. This double-sided heat dissipation solution can accelerate the heat dissipation of the power chips and improve the heat dissipation capacity of the power module. Moreover, a clip is arranged between the first copper-clad board and the second copper-clad board, and the clip is used to realize the electrical interconnection between the power chip and the first copper-clad board or the second copper-clad board. The area of ​​the clip is relatively large, so that the clip can quickly transfer the heat of the power chip to the copper-clad board, further accelerating the heat dissipation of the power chip, thereby further improving the heat dissipation capacity of the power module.

[0008] In addition, this embodiment uses a clip arranged between the power chip and the copper clad board. In the power module packaging, it is only necessary to bond the clip to the surface of all power chips. Compared with bonding spacers to the surface of each power chip respectively, it can simplify the packaging process and improve the packaging efficiency.

[0009] In a possible implementation manner, the copper layer of the first copper-clad laminate has electrically interconnected circuits;

[0010] The bottom surfaces of the m power chips are all welded on the surface of the first copper-clad board, wherein the bottom surface of the power chip is the bottom surface of the substrate of the power chip;

[0011] The clip is located between the top surfaces of the m power chips and the second copper clad laminate, and is connected to the first copper clad laminate, wherein the top surface of the power chip is a surface of the substrate facing away from the power chip.

[0012] In the scheme shown in the present disclosure, the bottom surface of each power chip is welded to the first copper clad laminate, thereby realizing that the electrode on the bottom surface of each power chip is directly electrically connected to the first copper clad laminate. The top surface of each power chip is connected to the first copper clad laminate through a clip, thereby realizing that the electrode on the top surface of each power chip is indirectly electrically connected to the first copper clad laminate through a clip. Thus, each power chip is electrically connected to an external circuit through the first copper clad laminate. In this way, the first copper clad laminate is used to realize electrical interconnection on the one hand and heat dissipation on the other hand, while the second copper clad laminate is used to realize heat dissipation.

[0013] In a possible implementation manner, the copper layer of the first copper clad laminate and the copper layer of the second copper clad laminate both have electrically interconnected lines, and m is an integer greater than or equal to 2;

[0014] The bottom surface of the first power chip among the m power chips is welded on the surface of the first copper-clad board, wherein the bottom surface of the first power chip is the bottom surface of the substrate of the first power chip;

[0015] The bottom surface of the second power chip among the m power chips is welded on the surface of the second copper-clad board, wherein the bottom surface of the second power chip is the bottom surface of the substrate of the second power chip;

[0016] The first part of the clip is located between the top surface of the first power chip and the second copper clad laminate, and is connected to the first copper clad laminate, and the top surface of the first power chip is a surface of the substrate facing away from the first power chip;

[0017] The second part of the clip is located between the top surface of the second power chip and the first copper clad laminate, and is connected to the second copper clad laminate, and the top surface of the second power chip is the surface of the substrate facing away from the second power chip;

[0018] The first portion and the second portion of the clip are connected.

[0019] Therein, the number of the first power chip is at least one, and the number of the second power chip is at least one.

[0020] In the scheme shown in the present disclosure, the bottom surface of each first power chip is welded to the first copper clad laminate, thereby realizing that the electrode on the bottom surface of each first power chip is directly electrically connected to the first copper clad laminate. The top surface of each first power chip is connected to the first copper clad laminate through a clip, thereby realizing that the electrode on the top surface of each first power chip is indirectly electrically connected to the first copper clad laminate through a clip. Thus, each first power chip is electrically connected to an external circuit through the first copper clad laminate. In this way, the first copper clad laminate is used to realize electrical interconnection on the one hand and heat dissipation on the other hand.

[0021] In the scheme shown in the present disclosure, the bottom surface of each second power chip is welded to the second copper clad laminate, thereby realizing that the electrode on the bottom surface of each second power chip is directly electrically connected to the second copper clad laminate. The top surface of each second power chip is connected to the second copper clad laminate through a clip, thereby realizing that the electrode on the top surface of each second power chip is indirectly electrically connected to the second copper clad laminate through a clip. Thus, each second power chip is electrically connected to the external circuit through the second copper clad laminate. In this way, the second copper clad laminate is used to realize electrical interconnection on the one hand and heat dissipation on the other hand.

[0022] In a possible implementation manner, the clip has m connecting pieces, and the connecting pieces are connected one by one to the top surfaces of the power chips.

[0023] In a possible implementation manner, the m is an integer greater than or equal to 2, and the two power chips are electrically connected via the clip.

[0024] In the solution shown in the present disclosure, there are multiple power chips. If there is an electrical interconnection between two power chips, then the electrical interconnection can be achieved through clip.

[0025] In a possible implementation, the clip is made of copper.

[0026] In the solution shown in the present disclosure, the clip made of copper has good electrical and thermal conductivity.

[0027] In a possible implementation, both the first copper clad laminate and the second copper clad laminate are copper clad ceramic laminates.

[0028] In the scheme shown in the present disclosure, the first copper-clad laminate and the second copper-clad laminate are both copper-clad ceramic laminates, which structurally include a ceramic plate and a copper layer located on the upper surface of the ceramic plate, and a copper layer located on the lower surface of the ceramic plate, wherein the copper layer can also be etched with a pattern to serve as an electrical interconnection line.

[0029] In a possible implementation, the first copper-clad laminate is a direct copper-clad DBC ceramic plate or an active metal brazed AMB ceramic plate, and the second copper-clad laminate is a direct copper-clad DBC ceramic plate or an active metal brazed AMB ceramic plate.

[0030] In the scheme shown in the present disclosure, the DBC ceramic board is copper-clad using the DBC process, that is, the direct sintering process, which is also called the direct bonding copper process. The copper layer of the DBC ceramic board is relatively thick and has good heat resistance. It is mainly used in the packaging of high-power and large temperature-change power modules.

[0031] In the solution disclosed in the present disclosure, the AMB ceramic plate is copper-clad using the AMB process. Similar to the DBC process, the copper layer of the AMB ceramic plate is also relatively thick and has good heat resistance. It is also mainly used in the packaging of power modules with high power and large temperature changes. However, the AMB ceramic plate made by the AMB process has stronger metal bonding, better thermal cycles, and higher electrical performance.

[0032] In a possible implementation manner, the power chip and the clip are fixedly connected by solder or sintered silver or sintered copper;

[0033] The power chip and the copper clad laminate are fixedly connected by solder or sintered silver or sintered copper, and the copper clad laminate is the first copper clad laminate or the second copper clad laminate;

[0034] The clip and the copper clad laminate are fixedly connected by solder or sintered silver or sintered copper, and the copper clad laminate is the first copper clad laminate or the second copper clad laminate.

[0035] In a possible implementation manner, the power module further includes a molding compound, and the first copper clad laminate, the second copper clad laminate, the m power chips, and the strip clip are all encapsulated in the molding compound.

[0036] In the solution shown in the present disclosure, the power chip is wrapped in a plastic packaging material to ensure good airtightness of the power chip.

[0037] In a possible implementation manner, the power module further includes a heat dissipation structure;

[0038] The first copper clad laminate and / or the second copper clad laminate is / are provided with the heat dissipation structure on a surface facing away from the m power chips.

[0039] In the solution shown in the present disclosure, the heat dissipation structure can dissipate the heat of the power chip to the outside, further improving the heat dissipation capacity of the power module.

[0040] In a possible implementation manner, the power module further includes a thermal interface material TIM, and the TIM is located on a surface of the heat dissipation structure facing the power chip.

[0041] In the solution shown in the present disclosure, the heat dissipation structure is directly mounted on the copper clad laminate, then the TIM is filled between the heat dissipation structure and the copper clad laminate to absorb the gap between the heat dissipation structure and the copper clad laminate. For another example, the heat dissipation structure is mounted on the copper clad laminate through the base plate, then the TIM is filled between the heat dissipation structure and the base plate to absorb the air gap between the heat dissipation structure and the base plate, thereby reducing thermal resistance.

[0042] In a possible implementation, the heat dissipation structure is a radiator or a liquid cooling plate.

[0043] In a second aspect, a power device is provided, the power device comprising a mainboard and the power module described in the first aspect, wherein the power module is located on the mainboard and is used to realize power conversion. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic diagram of a structure of a power module in which a power chip is electrically connected to a first copper-clad laminate according to an exemplary embodiment of the present disclosure;

[0045] Figure 2 is a schematic diagram of a structure of a power module in which a power chip is electrically connected to a second copper-clad laminate according to an exemplary embodiment of the present disclosure;

[0046] Figure 3 It is a schematic diagram of the structure of a power module provided by an exemplary embodiment of the present disclosure, in which a portion of power chips is electrically connected to a first copper-clad laminate, and another portion of power chips is electrically connected to a second copper-clad laminate;

[0047] Figure 4 is a schematic diagram of a clip of a power module provided by an exemplary embodiment of the present disclosure;

[0048] Figure 5 yes Figure 1 The schematic diagram of the fixing relationship inside the power module shown is realized by solder or sintered silver or sintered copper;

[0049] Figure 6 yes Figure 1 The schematic diagram of the structure of the power module shown is encapsulated by plastic packaging material;

[0050] Figure 7 yes Figure 1 The power module shown also includes a structural schematic diagram of the heat dissipation structure.

[0051] Legend

[0052] 1. First copper-clad board; 11. First ceramic board; 2. Second copper-clad board; 21. Second ceramic board; 3. Power chip; 31. First power chip; 32. Second power chip; 4. Clip; 40. Connecting piece; 41. First part; 42. Second part; 5. Plastic encapsulation material; 6. Bottom plate; 7. Heat dissipation structure; 8. TIM. DETAILED DESCRIPTION

[0053] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0054] The present embodiment relates to a power module, which is specifically a power module with relatively high power, such as an insulated gate bipolar transistor (IGBT) module, a silicon carbide SiC module, a power module, etc.

[0055] As the performance of these power modules increases, their operating power is also getting larger and larger. As the degree of integration increases, the number of power chips included is also increasing. These will aggravate the heat generation of the power modules, so heat dissipation performance is one of the bottlenecks restricting the development of power modules.

[0056] In order to improve the heat dissipation capacity of the power module, the bare chip (die) of the power module is usually arranged on a copper clad board in the package. The copper clad board includes a ceramic board and a copper layer laid on the upper and lower surfaces of the ceramic board. The copper layer on the surface of the ceramic board can also be etched into a circuit pattern. Therefore, the power chip is arranged on the copper clad board, which not only plays the role of electrical interconnection, but also plays the role of heat dissipation for the power chip.

[0057] Although the copper clad plate is used to dissipate heat for the power chip, the heat dissipation capacity of the power module is still not strong. In order to further improve the heat dissipation capacity of the power module, this embodiment provides a power module that can further improve the heat dissipation capacity of the power module by increasing the heat dissipation area.

[0058] The power module described in this embodiment will be introduced below.

[0059] Before introducing the power module, the position terms involved in this embodiment are first explained.

[0060] The upper and lower relationships described in the embodiments of the present disclosure are based on the upper and lower relationships shown in the accompanying drawings unless otherwise specified. The top surface of the power chip, unless otherwise specified, refers to the surface of the power chip facing away from its substrate, also known as the front surface of the power chip. The bottom surface of the power chip, unless otherwise specified, refers to the bottom surface of the substrate of the power chip, also known as the back surface of the power chip.

[0061] like Figure 1 The following is a schematic diagram of the power module structure. Figure 1 As shown, the power module includes a first copper clad laminate 1 , a second copper clad laminate 2 and m power chips 3 .

[0062] refer to Figure 1 As shown, the first copper-clad laminate 1 structurally includes a ceramic board, a copper layer located on the upper surface of the ceramic board and a copper layer located on the lower surface of the ceramic board, so the first copper-clad laminate 1 can also be a copper-clad ceramic board.

[0063] refer to Figure 1 As shown, for the convenience of description, the ceramic board of the first copper clad board 1 is denoted as the first ceramic board 11, the copper layer located on the upper surface of the first ceramic board 11 is denoted as the upper copper layer a, and the copper layer located on the lower surface of the first ceramic board 11 is denoted as the lower copper layer b.

[0064] Similarly, the second copper-clad board 2 also structurally includes a ceramic board, a copper layer located on the upper surface of the ceramic board, and a copper layer located on the lower surface of the ceramic board, so the second copper-clad board 2 can also be a copper-clad ceramic board.

[0065] refer to Figure 1 As shown, for the convenience of description, the ceramic board of the second copper clad board 2 is recorded as the second ceramic board 21, the copper layer located on the upper surface of the second ceramic board 21 is also recorded as the upper copper layer a, and the copper layer located on the lower surface of the second ceramic board 21 is also recorded as the lower copper layer b.

[0066] In one example, the first copper-clad laminate 1 may be a direct bond copper (DBC) ceramic plate or an active metal brazing (AMB) ceramic plate. Similarly, the second copper-clad laminate 2 may be a DBC ceramic plate or an AMB ceramic plate.

[0067] Among them, the DBC ceramic board is copper-clad using the DBC process, and has the characteristics of a relatively thick copper layer and good heat resistance. It is mainly used in the packaging of high-power and large temperature-change power modules.

[0068] Among them, the AMB ceramic board is copper-clad using the AMB process, and also has the characteristics of a relatively thick copper layer and good heat resistance. However, compared with the DBC ceramic board, the AMB ceramic board also has stronger metal bonding, better thermal cycle, and higher electrical performance. The AMB ceramic board is also mainly used in the packaging of high-power and large temperature-change power modules.

[0069] In one example, the power chip 3 of the power module is an unpackaged bare chip, also called a bare die. The number of power chips 3 is at least one, so m is an integer greater than or equal to 1. For ease of introduction, in this embodiment, m=2 is used as an example, and the power module includes two power chips 3. The two power chips 3 are respectively recorded as a first power chip 31 and a second power chip 32 for distinction.

[0070] Continue to refer Figure 1 As shown, m power chips 3 are located between the first copper clad board 1 and the second copper clad board 2, so that the heat of each power chip 3 can be transferred in both the upward and downward directions. The heat transferred to the first copper clad board 1 is dissipated outwards through the first copper clad board 1, and the heat transferred to the second copper clad board 2 is dissipated outwards through the second copper clad board 2. This double-sided heat dissipation of the power chip 3 can speed up the heat dissipation of the power chip 3 and improve the heat dissipation capacity of the power module.

[0071] The electrical interconnection between the power chip 3 and the first copper clad laminate 1 or the second copper clad laminate 2 is described below.

[0072] The power chip 3 is electrically interconnected with the copper clad laminate, that is, the electrode of the power chip 2 is electrically connected to the copper clad laminate, and the electrode of the power chip 3 is also called a pad.

[0073] In one example, because the power chip 3 is packaged in a closed environment, the electrodes of the power chip 3 need to be connected to the circuits of the copper clad laminate before packaging, so that the power chip 3 can be connected to the outside through the copper clad laminate. In this way, the external circuit (such as a drive circuit or a control circuit) can input signals to the power chip 3 by being electrically connected to the copper clad laminate.

[0074] The top and bottom surfaces of the power chip 3 are both provided with electrodes. For example, the top surface of the power chip 3 is provided with a source and a gate, and the bottom surface of the power chip 3 is provided with a drain.

[0075] In this embodiment, the top surface of the power chip 3 may also be referred to as the front surface of the power chip 3, which refers to the surface facing away from the substrate of the power chip 3. The bottom surface of the power chip 3 may also be referred to as the back surface of the power chip 3, which refers to the bottom surface of the substrate of the power chip 3, and is also the outer surface of the substrate of the power chip 3 facing away from other layers.

[0076] In one example, the copper layer of the first copper clad laminate 1 has electrically interconnected circuits, and the electrodes of the power chip 3 can be connected to the circuits of the first copper clad laminate 1 , so that the power chip 3 can be connected to the outside through the first copper clad laminate 1 .

[0077] For example, the electrode on the top surface of the power chip 3 is electrically connected to the first copper clad laminate 1 , and the electrode on the bottom surface of the power chip 3 is electrically connected to the first copper clad laminate 1 , so that the power chip 3 can be connected to the outside through the first copper clad laminate 1 .

[0078] refer to Figure 1 As shown, the power chip 3 is located on the inner surface of the first copper-clad board 1 (i.e. Figure 1 The upper surface of the upper copper layer a of the first copper clad laminate 1 is welded to the bottom surface of the power chip 3, and the inner surface of the first copper clad laminate 1 is welded. In this way, the electrode on the bottom surface of the power chip 3 is electrically connected to the first copper clad laminate 1 through welding. The top surface of the power chip 3 can be connected to the first copper clad laminate 1 through a clip (strip) 4. Furthermore, the electrodes on the top and bottom surfaces of the power chip 3 are electrically connected to the first copper clad laminate 1, and the power chip 3 is connected to the outside through the first copper clad laminate 1.

[0079] Continue to refer Figure 1 As shown, in order to connect the electrode on the top surface of the power chip 3 with the electrode on the inner surface of the first copper clad laminate 1, correspondingly, clip 4 is located between the power chip 3 and the second copper clad laminate 2, and extends between the power chip 3 and the second copper clad laminate 2, and bends toward the first copper clad laminate 1 to be connected to the electrode of the first copper clad laminate 1.

[0080] in, Figure 1 The electrodes of the medium power chip 3 are not shown, and only one electrode (but not limited to one) is shown on the inner surface of the first copper clad laminate 1. The electrode on the inner surface of the first copper clad laminate 1 is also a local area of ​​the upper copper layer a.

[0081] refer to Figure 1 As shown, clip 4 is bent, with one part approaching the first copper clad laminate 1 and connected to the first copper clad laminate 1 , and the other part approaching the second copper clad laminate 2 and sandwiched between the power chip 3 and the second copper clad laminate 2 .

[0082] In another example, the copper layer of the second copper clad laminate 2 has electrically interconnected circuits, and the electrodes of the power chip 3 can be connected to the circuits of the second copper clad laminate 2 , so that the power chip 3 can be connected to the outside through the second copper clad laminate 2 .

[0083] For example, the electrode on the top surface of the power chip 3 is electrically connected to the second copper clad laminate 2 , and the electrode on the bottom surface of the power chip 3 is electrically connected to the second copper clad laminate 2 , so that the power chip 3 can be connected to the outside through the second copper clad laminate 2 .

[0084] like Figure 2 As shown, the power chip 3 is located on the inner surface of the second copper-clad board 2 (i.e. Figure 2 The bottom surface of the power chip 3 is welded to the inner surface of the second copper clad laminate 2, and the bottom surface of the power chip 3 is welded to the inner surface of the second copper clad laminate 2. In this way, the electrode on the bottom surface of the power chip 3 is electrically connected to the second copper clad laminate 2 by welding. The top surface of the power chip 3 can be connected to the second copper clad laminate 2 by a clip (strip) 4. Furthermore, the electrodes on the top and bottom surfaces of the power chip 3 are electrically connected to the second copper clad laminate 2, and the power chip 3 is connected to the outside through the second copper clad laminate 2.

[0085] Continue to refer Figure 2 As shown, in order to connect the electrode on the top surface of the power chip 3 with the electrode on the inner surface of the second copper clad laminate 2, correspondingly, clip 4 is located between the power chip 3 and the first copper clad laminate 1, and extends between the power chip 3 and the first copper clad laminate 1, and bends toward the second copper clad laminate 2 to be connected to the second copper clad laminate 2.

[0086] in, Figure 2 The electrodes of the medium-power chip 3 are not shown, and only one electrode (but not limited to one) is shown on the inner surface of the second copper-clad laminate 2. The electrode on the inner surface of the second copper-clad laminate 2 is also a local area of ​​the lower copper layer b.

[0087] refer to Figure 2 As shown, clip 4 is bent, with one part approaching the second copper clad laminate 2 and connected to the second copper clad laminate 2 , and the other part approaching the first copper clad laminate 1 and sandwiched between the power chip 3 and the first copper clad laminate 1 .

[0088] in, Figure 1 It is shown that the electrodes of all power chips 3 are electrically connected to the outside through the first copper clad laminate 1. The first copper clad laminate 1 is used for heat dissipation and electrical interconnection, and the second copper clad laminate 2 is used for heat dissipation. Figure 2 It is shown that the electrodes of all power chips 3 are electrically connected to the outside through the second copper clad laminate 2. The second copper clad laminate 2 is used for heat dissipation and electrical interconnection, while the first copper clad laminate 1 is used for heat dissipation.

[0089] In another example, the copper layer of the first copper clad laminate 1 and the copper layer of the second copper clad laminate 2 both have electrically interconnected lines, the number of power chips 3 is multiple, and the electrodes of a part of the power chips 3 can be connected to the first copper clad laminate 1 to achieve external electrical connection, and the electrodes of another part of the power chips 3 can be connected to the second copper clad laminate 2 to achieve external electrical connection.

[0090] For example, the electrode of the first power chip 31 among the multiple power chips 3 is electrically connected to the first copper clad laminate 1, and the electrode of the second power chip 32 among the multiple power chips 3 is electrically connected to the second copper clad laminate 2. The number of the first power chip 31 is at least one, and the number of the second power chip 32 is at least one. Figure 3 A first power chip 31 and a second power chip 32 are used as an example.

[0091] refer to Figure 3 As shown, the first power chip 31 is located on the inner surface of the first copper clad board 1, and the bottom surface of the first power chip 31 is welded to the inner surface of the first copper clad board 1, and the top surface of the first power chip 31 is connected to the first copper clad board 1 through clip 4. Furthermore, the electrodes on the top and bottom surfaces of the first power chip 31 are connected to the first copper clad board 1, and the first power chip 31 is electrically connected to the outside through the first copper clad board 1.

[0092] Continue to refer Figure 3 As shown, the second power chip 32 is located on the inner surface of the second copper clad board 2, and the bottom surface of the second power chip 32 is welded to the inner surface of the second copper clad board 2, and the top surface of the second power chip 32 is connected to the second copper clad board 2 through clip 4. Furthermore, the electrodes on the top and bottom surfaces of the second power chip 32 are connected to the second copper clad board 2, and the second power chip 32 is electrically connected to the outside through the second copper clad board 2.

[0093] Continue to refer Figure 3 As shown, clip 4 connects the electrode on the top surface of the first power chip 31 with the electrode on the inner surface of the first copper clad laminate 1 , and clip 4 connects the electrode on the top surface of the second power chip 32 with the electrode on the inner surface of the second copper clad laminate 2 .

[0094] So, reference Figure 3 As shown, clip4 includes a first part 41 and a second part 42 that are connected, wherein the first part 41 of clip4 is located between the first power chip 31 and the second copper clad laminate 2, and extends between the first power chip 31 and the second copper clad laminate 2, and bends toward the first copper clad laminate 1, and is connected to the first copper clad laminate 1, and the second part 42 of clip4 is located between the second power chip 32 and the first copper clad laminate 1, and extends between the second power chip 32 and the first copper clad laminate 1, and bends toward the second copper clad laminate 2, and is connected to the second copper clad laminate 2.

[0095] It should be pointed out that Figure 3 The first copper clad laminate 1 and the second copper clad laminate 2 are used for both heat dissipation and electrical interconnection.

[0096] It should be pointed out that if there is an electrical interconnection between the power chips 3, the electrical interconnection can also be achieved through clip 4. Of course, the electrical interconnection between the power chips 3 can also be achieved through the first copper clad laminate 1 or the second copper clad laminate 2.

[0097] Based on the above, it can be known that to which copper-clad board the power chip 3 is electrically connected, it is only necessary to weld the bottom surface of the power chip 3 to the inner surface of the copper-clad board, and connect the top surface of the power chip 3 to the electrode on the inner surface of the copper-clad board through clip 4. Therefore, this embodiment does not limit the position arrangement of clip 4, as long as the top surface of the power chip 3 is connected to the copper-clad board to which the power chip 3 is welded through clip 4.

[0098] Based on the above, reference Figure 4 As shown, clip 4 has connecting pieces 40 , and the number of connecting pieces 40 is equal to the number of power chips 3 , both of which are m. The connecting pieces 40 are fixedly connected to the top surfaces of the power chips 3 one by one.

[0099] In one example, in a solution where m is greater than or equal to 2, reference Figure 4 As shown, there may be a gap between the connecting pieces 40 , but the m connecting pieces 40 are interconnected and are integrally processed.

[0100] The function of clip4 is introduced below.

[0101] In an example, the material of clip4 may be a conductive metal, such as copper and aluminum, etc. As an example, the material of clip4 is copper, then clip4 may also be called Cu-clip.

[0102] In one example, electrical connection is achieved through clip 4, which has advantages such as increased current carrying capacity and reduced line resistance and parasitic inductance compared to electrical connection achieved through bond wires.

[0103] In addition, clip4 not only has advantages in electrical connection, but also in heat dissipation, it can improve the heat dissipation capacity of the power module. This is because clip4 is in contact with all power chips 3, and the area of ​​clip4 is relatively large. For example, the area of ​​clip4 is larger than the area of ​​any power chip 3. Then, when the heat on a power chip is transferred to the copper clad laminate via clip4, clip4 can quickly absorb the heat on the power chip and transfer the heat to the copper clad laminate because of its large area.

[0104] For example, refer to Figure 1As shown, the heat generated by the power chip 3 is directly transferred downward to the first copper clad board 1, and then quickly transferred upward to the second copper clad board 2 through the large-area clip 4, thereby dissipating heat outward through the first copper clad board 1 and the second copper clad board 2. Figure 2 As shown, the heat generated by the power chip 3 is directly transferred upward to the second copper clad board 2, and then quickly transferred downward to the first copper clad board 1 through the large-area clip 4, thereby dissipating heat outward through the first copper clad board 1 and the second copper clad board 2. Figure 3 As shown, the heat generated by the first power chip 31 is directly transferred downward to the first copper clad laminate 1, and is quickly transferred upward to the second copper clad laminate 2 via the large-area clip 4, thereby dissipating the heat outward via the first copper clad laminate 1 and the second copper clad laminate 2. The heat generated by the second power chip 32 is directly transferred upward to the second copper clad laminate 2, and is quickly transferred downward to the first copper clad laminate 1 via the large-area clip 4, thereby dissipating the heat outward via the first copper clad laminate 1 and the second copper clad laminate 2.

[0105] It can be seen that no matter what the position of clip 4 is, the heat of the power chip 3 can be quickly transferred to the soldered copper clad board. Moreover, the more power chips 3 there are and the larger the area of ​​clip 4 is, the more obvious the advantage of clip 4 in improving heat dissipation performance will be.

[0106] In one example, the shape of clip 4 is mainly related to the number of power chips 3, the position layout of these power chips 3, and which copper clad board each power chip 3 is electrically connected to. For example, the shape of clip 4 can be frame, band or strip.

[0107] For example, Figure 4 The figure shows a schematic diagram of clip4. Figure 4 A schematic diagram showing two power chips 3 connected in parallel via clip 4 is shown.

[0108] The present embodiment does not limit the specific shape of clip4, and it can be flexibly designed according to actual conditions.

[0109] The following introduces other features of the power module. For ease of introduction, they can be described as follows: Figure 1 The structure of the power module shown is schematically illustrated.

[0110] In an example, the fixed connection inside the power module may be connected by solder, sintered silver, or sintered copper.

[0111] For example, refer to Figure 5As shown, the bottom surface of the power chip 3 is fixedly connected to the upper copper layer a of the first copper clad board 1 by solder or sintered silver or sintered copper. The top surface of the power chip 3 and clip4 can be fixedly connected by solder or sintered silver or sintered copper. Clip4 and the lower copper layer b of the second copper clad board 2 can be fixedly connected by solder or sintered silver or sintered copper. Clip4 and the electrode of the first copper clad board 1 are fixedly connected by solder or sintered silver or sintered copper. Among them, Figure 5 The black filled portion in the is solder or sintered silver or sintered copper.

[0112] like Figure 6 The following is a schematic diagram of the power module structure. Figure 6 As shown, the power module further includes a plastic packaging material 5 , in which the first copper clad board 1 , the second copper clad board 2 , m power chips 3 and clip 4 are all packaged.

[0113] In one example, in order to prevent the plastic encapsulation material 5 from interfering with the heat dissipation of the first copper clad board 1 and the second copper clad board 2, accordingly, as Figure 6 As shown, the upper surface of the plastic encapsulation material 5 is flush with the outer surface of the second copper clad board 2 facing away from the power chip 3, that is, the upper surface of the plastic encapsulation material 5 is flush with the outer surface of the upper copper layer a of the second copper clad board 2. Alternatively, the outer surface of the upper copper layer a of the second copper clad board 2 may be exposed.

[0114] Continue to refer Figure 6 As shown, the lower surface of the plastic encapsulation material 5 is flush with the outer surface of the first copper clad board 1 facing away from the power chip 3, that is, the lower surface of the plastic encapsulation material 5 is flush with the outer surface of the lower copper layer b of the first copper clad board 1. Alternatively, the outer surface of the lower copper layer b of the first copper clad board 1 may be exposed.

[0115] In one example, in order to further improve the heat dissipation capability of the power module, Figure 7 As shown in the figure, it is a schematic diagram of the structure of the power module. Figure 7 As shown, the power module further includes a heat dissipation structure 7, wherein the heat dissipation structure 7 may specifically be a radiator or a liquid cooling plate. Figure 7 A heat sink is used as an example.

[0116] In one example, the heat dissipation structure 7 can be located on the surface of the first copper clad laminate 1 facing away from the power chip 3, or can be installed on the surface of the second copper clad laminate 2 facing away from the power chip 3. A heat dissipation structure 7 can also be installed on the surface of the first copper clad laminate 1 facing away from the power chip 3, and a heat dissipation structure 7 can also be installed on the surface of the second copper clad laminate 2 facing away from the power chip 3.

[0117] For example, refer to Figure 7 As shown, the heat dissipation structure 7 is located below the first copper clad laminate 1 facing away from the power chip 3 .

[0118] In one example, due to the insufficient structural strength of the copper clad board, it is not easy to install the heat dissipation structure 7. Figure 7 As shown, the power module may further include a base plate 6 , which is located below the first copper clad laminate 1 facing away from the power chip 3 , and the heat dissipation structure 7 is installed below the base plate 6 facing away from the first copper clad laminate 1 .

[0119] The first copper clad laminate 1 and the bottom plate 6 may be fixedly connected by solder or sintered silver or sintered copper, as described above.

[0120] In an example, in order to transfer the heat on the first copper clad laminate 1 to the heat dissipation structure 7 and dissipate the heat outward through the heat dissipation structure 7, the base plate 6 is made of a thermally conductive material to enhance the heat transfer between the first copper clad laminate 1 and the heat dissipation structure 7.

[0121] In an example, in order to further enhance the heat transfer between the first copper clad board 1 and the heat dissipation structure 7, accordingly, as Figure 7 As shown, the power module further includes a thermal interface material (TIM) 8, wherein the TIM 8 is located on the surface of the heat dissipation structure 7 facing the first copper clad laminate 1. For example, the TIM is filled between the heat dissipation structure 7 and the base plate 6 to absorb the air gap between the heat dissipation structure 7 and the base plate 6 to reduce thermal resistance.

[0122] In this embodiment, the power module includes two copper-clad boards, a first copper-clad board and a second copper-clad board, and a plurality of power chips are located between the two copper-clad boards. Both copper-clad boards are used to dissipate heat for the plurality of power chips. This double-sided heat dissipation solution can accelerate the heat dissipation of the power chips and improve the heat dissipation capacity of the power module. Moreover, a clip is arranged between the first copper-clad board and the second copper-clad board, and the clip is used to realize the electrical interconnection between the power chip and the first copper-clad board or the second copper-clad board. The area of ​​the clip is relatively large, so that the clip can quickly transfer the heat of the power chip to the copper-clad board, further accelerating the heat dissipation of the power chip, thereby further improving the heat dissipation capacity of the power module.

[0123] In addition, this embodiment uses a clip arranged between the power chip and the copper clad board. In the power module packaging, it is only necessary to bond the clip to the surface of all power chips. Compared with bonding spacers (gaskets) on the surface of each power chip respectively, it can simplify the packaging process and improve the packaging efficiency.

[0124] This embodiment also provides a power device, which includes a mainboard and the power module described above, wherein the power module is arranged on the mainboard, the power module is electrically connected to other devices through the mainboard, and the power module is specifically used to realize power conversion.

[0125] The terms used in the embodiments of the present disclosure are only used to explain the embodiments of the present disclosure, and are not intended to limit the present disclosure. Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be the common meanings understood by people with ordinary skills in the field to which the present disclosure belongs. The "first", "second" and similar words used in the present disclosure specification and claims do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one" or "one" do not indicate a quantity limit, but indicate that there is at least one. Similar words such as "include" or "include" mean that the elements or objects appearing in front of "include" or "include" include the elements or objects listed after "include" or "include" and their equivalents, and do not exclude other elements or objects. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. "Multiple" refers to two or more, unless otherwise clearly defined.

Claims

1. A power module, characterized in that: The power module comprises a first copper-clad laminate (1), a second copper-clad laminate (2), m power chips (3) and a strip clip (4); The m power chips (3) and the clip (4) are both located between the first copper clad laminate (1) and the second copper clad laminate (2), and m is an integer greater than or equal to 1; Each power chip (3) is electrically connected to the first copper clad laminate (1) or the second copper clad laminate (2) via the clip (4).

2. The power module according to claim 1, characterized in that: The copper layer of the first copper-clad laminate (1) has electrically interconnected circuits; The bottom surfaces of the m power chips (3) are all welded on the surface of the first copper-clad laminate (1), wherein the bottom surface of the power chip (3) is the bottom surface of the substrate of the power chip (3); The clip (4) is located between the top surface of the m power chips (3) and the second copper clad laminate (2), and is connected to the first copper clad laminate (1), wherein the top surface of the power chip (3) is the surface of the substrate facing away from the power chip (3).

3. The power module according to claim 1, characterized in that: The copper layer of the first copper-clad laminate (1) and the copper layer of the second copper-clad laminate (2) both have electrically interconnected lines, and m is an integer greater than or equal to 2; The bottom surface of a first power chip (31) among the m power chips (3) is welded on the surface of the first copper-clad laminate (1), wherein the bottom surface of the first power chip (31) is the bottom surface of the substrate of the first power chip (31); The bottom surface of the second power chip (32) among the m power chips (3) is welded on the surface of the second copper-clad laminate (2), wherein the bottom surface of the second power chip (32) is the bottom surface of the substrate of the second power chip (32); The first part (41) of the clip (4) is located between the top surface of the first power chip (31) and the second copper-clad laminate (2), and is connected to the first copper-clad laminate (1), wherein the top surface of the first power chip (31) is the surface of the substrate facing away from the first power chip (31); The second portion (42) of the clip (4) is located between the second power chip (32) and the first copper-clad laminate (1), and is connected to the second copper-clad laminate (2), wherein the top surface of the second power chip (32) is the surface of the substrate facing away from the second power chip (32); The first part (41) and the second part (42) of the clip (4) are connected.

4. The power module according to claim 1, characterized in that: The clip (4) has m connecting pieces (40), and the connecting pieces (40) are connected one by one to the top surfaces of the power chips (3).

5. The power module according to claim 1, characterized in that: The material of the clip (4) is copper.

6. The power module according to claim 1, characterized in that: The first copper-clad laminate (1) is a direct copper-clad DBC ceramic plate or an active metal brazed AMB ceramic plate, and the second copper-clad laminate (2) is a direct copper-clad DBC ceramic plate or an active metal brazed AMB ceramic plate.

7. The power module according to claim 1, characterized in that: The power module further comprises a plastic encapsulation material (5), and the first copper clad laminate (1), the second copper clad laminate (2), the m power chips (3) and the clip (4) are all encapsulated in the plastic encapsulation material (5).

8. The power module according to claim 7, characterized in that: The first surface of the molding compound (5) is flush with the outer surface of the first copper clad laminate (1) facing away from the power chip (3), and the second surface of the molding compound (5) is flush with the outer surface of the second copper clad laminate (2) facing away from the power chip (3).

9. The power module according to any one of claims 1 to 8, characterized in that: The power module also includes a heat dissipation structure (7); The first copper clad laminate (1) and / or the second copper clad laminate (2) is / are provided with the heat dissipation structure (7) on an outer surface facing away from the m power chips (3).

10. A power device, characterized in that: The power device comprises a mainboard and a power module according to any one of claims 1 to 9, wherein the power module is arranged on the mainboard and is used to perform power conversion.

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