Efficient heat dissipation structure for power module

Abstract

The invention relates to the field of power module heat dissipation, and discloses an efficient heat dissipation structure for a power module, which comprises a power module, a first heat conduction module, a second heat conduction module and a heat dissipation module, the power module comprises a chip and a DBC assembly, the chip is welded above the DBC assembly, and the chip and the DBC assembly are provided with solder layers used for transferring heat. The heat conduction end of the first heat conduction module is connected with the heat dissipation end of the DBC assembly, and the heat dissipation end of the first heat conduction module is connected with the first heat collection end of the heat dissipation module; the second heat conduction module comprises a bonding piece and a plastic package heat conduction layer, the two ends of the bonding piece are welded to the upper end face of the chip and the upper end face of the DBC assembly respectively, the plastic package heat conduction layer is located above the chip, the chip and the bonding piece are subjected to plastic package through the plastic package heat conduction layer, and the plastic package heat conduction layer is connected with the second heat collection end of the heat dissipation module; therefore, the chip can conduct away heat in parallel through two paths, so that the problem of low heat dissipation efficiency of the power module in the prior art is solved.

Description

Technical Field

[0001] This invention relates to the field of power module heat dissipation technology, and in particular to a high-efficiency heat dissipation structure for power modules. Background Technology

[0002] Currently, the power module inside the drive motor controller of new energy vehicles usually uses SiC chips. SiC chips are usually soldered to a copper surface. The copper surface is connected to the lower copper layer using an insulating material. The lower copper layer is soldered to the copper substrate. Heat dissipation pins are arranged below the copper substrate. The copper substrate and the motor controller housing form a closed space, through which coolant is circulated to remove the heat generated during chip operation.

[0003] As can be seen from the above description of the existing heat dissipation path of power modules, the current heat dissipation path of power modules is very long, and the chip can only conduct heat to the cooling water channel through the bottom, resulting in low heat dissipation efficiency. In order to control the temperature rise of the power module chip and improve the output current capacity of the power module, more power modules often need to be connected in parallel, which leads to an overall increase in cost. Summary of the Invention

[0004] The purpose of this invention is to provide a high-efficiency heat dissipation structure for power modules, which solves the problem of low heat dissipation efficiency of power modules in the prior art.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: In a first aspect, the present invention discloses a high-efficiency heat dissipation structure for a power module, comprising a power module, a first heat-conducting module, a second heat-conducting module, and a heat dissipation module; The power module includes a chip and a DBC component, the chip being soldered on top of the DBC component, and the chip and the DBC component having a solder layer for heat transfer; The heat-conducting end of the first heat-conducting module is connected to the heat dissipation end of the DBC component, and the heat dissipation end of the first heat-conducting module is connected to the first heat collection end of the heat dissipation module. The second thermal conductive module includes a bonding sheet and a plastic encapsulation thermal conductive layer. The two ends of the bonding sheet are respectively welded to the upper surface of the chip and the upper surface of the DBC component. The plastic encapsulation thermal conductive layer is located above the chip and encapsulates the chip and the bonding sheet. The plastic encapsulation thermal conductive layer is connected to the second heat collection end of the heat dissipation module. The heat dissipation module transfers the heat collected by the first heat collection end and the second heat collection end.

[0006] As an optional solution, the first heat-conducting module includes a heat-dissipating substrate, the DBC component is disposed on the heat-conducting plate of the heat-dissipating substrate, and the heat-dissipating end of the heat-dissipating substrate is connected to the first heat-collecting end of the heat-dissipating module.

[0007] As an optional option, the molding material of the heat-conducting plastic layer is a thermally conductive epoxy potting compound.

[0008] As an optional solution, the gaps between the chip, the DBC component and the first and second thermally conductive modules are encapsulated with thermally conductive epoxy potting compound.

[0009] As an optional solution, the second heat collection end of the heat dissipation module is a heat pipe.

[0010] Alternatively, the two ends of the heat pipe are designated as a first end and a second end, respectively. The first end is connected to the second thermally conductive end of the first thermally conductive module, the second end is connected to the plastic encapsulation thermally conductive layer, and the second end is located above the chip.

[0011] As an alternative, the first end and the second end are staggered in the vertical direction.

[0012] As an optional solution, the heat dissipation module is a water-cooled radiator, which includes a cold plate, cooling pipes, a liquid storage tank, and a water pump. The cold plate collects the heat collected by the first heat collection end and the second heat collection end; The wall of the cooling pipe is in contact with the cold plate, the inlet of the cooling pipe is connected to the outlet of the water pump, and the outlet of the cooling pipe is connected to the storage tank. The inlet of the water pump is connected to the storage tank, and the water pump pumps the cooling medium in the storage tank into the cooling pipe.

[0013] The present invention has the following unexpected beneficial effects: 1. The chip that generates the most heat in the power module of the present invention can conduct heat to the first heat conduction module and the second heat conduction module, and both the first heat conduction module and the second heat conduction module are connected to the heat dissipation module, so that the chip can conduct heat away through two parallel paths, thereby solving the problem of low heat dissipation efficiency of power modules in the prior art.

[0014] 2. This invention increases the heat dissipation efficiency of the chip's upper surface through the bonding sheet + high thermal conductivity structure, making the internal temperature distribution of the chip more uniform. This solves the problem of chip failure caused by thermal stress due to uneven temperature, thereby increasing the chip's reliability and service life.

[0015] 3. The thermally conductive plastic encapsulation layer material of the present invention is thermally conductive epoxy potting compound. This material has good thermal conductivity while encapsulating the chip. In addition, because the material itself is insulating, it can be assembled with heat pipes with low thermal resistance but high conductivity, thereby improving the heat dissipation efficiency of the chip while ensuring stable chip operation. Attached Figure Description

[0016] Figure 1 This is an overall schematic diagram of a high-efficiency heat dissipation structure for a power module according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the upper surface of a chip for a high-efficiency heat dissipation structure for a power module according to an embodiment of the present invention; Figure 3 This is an exploded view of a high-efficiency heat dissipation structure for a power module according to an embodiment of the present invention; Figure 4 This is a cross-sectional view of a high-efficiency heat dissipation structure for a power module according to an embodiment of the present invention; Figure 5 This is a top view of a high-efficiency heat dissipation structure for a power module according to an embodiment of the present invention; In the figure, 1 is the power module; 101 is the chip; 102 is the DBC component; 2 is the first heat conduction module; 201 is the heat dissipation substrate; 3 is the second heat conduction module; 301 is the bonding sheet; 302 is the plastic encapsulation heat conduction layer; 4 is the heat dissipation module; 401 is the heat pipe; 4011 is the first end; 4012 is the second end. Detailed Implementation

[0017] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0018] In one embodiment, such as Figures 1 to 5 As shown, in a first aspect, the present invention provides a high-efficiency heat dissipation structure for a power module 1, comprising a power module 1, a first heat-conducting module 2, a second heat-conducting module 3, and a heat dissipation module 4.

[0019] The power module 1 includes a chip 101 and a DBC component 102. The chip 101 is soldered on top of the DBC component 102. The chip 101 and the DBC component 102 have a solder layer for heat transfer. The solder layer is soldered between the chip 101 and the DBC component 102. The solder layer transfers the heat emitted from the bottom of the chip 101 when it is working to the DBC component 102.

[0020] The heat-conducting end of the first heat-conducting module 2 is connected to the heat dissipation end of the DBC component 102, and the heat dissipation end of the first heat-conducting module 2 is connected to the first heat-collecting end of the heat dissipation module 4.

[0021] The second heat-conducting module 3 includes a bonding sheet 301 and a plastic-encapsulated heat-conducting layer 302. The two ends of the bonding sheet 301 are respectively welded to the upper end face of the chip 101 and the upper end face of the DBC component 102. The plastic-encapsulated heat-conducting layer 302 is located above the chip 101 and encapsulates the chip 101 and the bonding sheet 301. The plastic-encapsulated heat-conducting layer 302 is connected to the second heat collection end of the heat dissipation module 4.

[0022] The heat dissipation module 4 transfers the heat collected by the first heat collection end and the second heat collection end.

[0023] Based on this, the power module 1 is provided with a chip 101 and a DBC component 102. A solder layer for heat conduction is welded between the chip 101 and the DBC component 102. The heat-conducting end of the first heat-conducting module 2 is connected to the heat dissipation end of the DBC component 102. The first heat-conducting module 2 transfers the heat emitted from the lower surface of the chip 101 to the heat dissipation module 4 through the path of "chip 101-DBC component 102-first heat-conducting module 2-heat dissipation module 4". The two ends of the bonding sheet 301 of the second heat-conducting module 3 are respectively welded to the upper end face of the chip 101 and the upper end face of the DBC component 102. The plastic encapsulation heat-conducting layer 302 of the second heat-conducting module 3 simultaneously bonds the bonding sheet... Both 301 and the chip 101 are encapsulated inside the bonding sheet 301. Therefore, the heat emitted from the upper surface of the chip 101 is directly conducted to the encapsulated thermal conductive layer 302 via the bonding sheet 301. The second thermal conductive module 3 transfers the heat emitted from the upper surface of the chip 101 to the heat dissipation module 4 through the path of "chip 101-bonding sheet 301-encapsulated thermal conductive layer 302-second thermal conductive module 3-heat dissipation module 4". This allows the chip 101 to obtain both upward and downward thermal conduction paths while being fixed by the encapsulated thermal conductive layer 302 to reduce its operating vibration. This improves the efficiency of heat transfer from the chip 101 to the heat dissipation module 4, thereby improving the heat dissipation efficiency of the chip 101 while ensuring stable operation.

[0024] Furthermore, such as Figures 1 to 5 As shown, the first heat-conducting module 2 includes a heat dissipation substrate 201, on which the DBC component 102 is disposed, and the heat dissipation end of the heat dissipation substrate 201 is connected to the first heat collection end of the heat dissipation module 4.

[0025] The type of heat dissipation substrate 201 is not further limited here. The heat dissipation substrate 201 is an aluminum substrate or a copper substrate. Due to the characteristics of the material itself, the heat dissipation substrate 201 has high thermal conductivity and structural strength. The heat dissipation substrate 201 provides more robust mechanical support for the DBC component 102 and the chip 101, thereby improving the module's vibration and impact resistance. The heat dissipation substrate 201 can also effectively diffuse the heat from the DBC component 102 laterally, so as to transfer the heat to the heat dissipation module 4 at a faster speed, thereby avoiding the accumulation of heat in a local area.

[0026] Furthermore, such as Figures 1 to 5 As shown, the molding material of the heat-conducting plastic layer 302 is a heat-conducting epoxy potting compound.

[0027] In the embodiments described in this patent, the preferred thermally conductive filler is an epoxy resin with added boron nitride and aluminum oxide particles. Since the epoxy resin has insulating properties, the encapsulated thermally conductive layer 302 ensures electrical insulation between the upper part of the chip 101 and the outside while conducting heat efficiently, thus improving safety. Furthermore, the epoxy resin can absorb and buffer the stress caused by thermal expansion and contraction between different materials (chip 101, bonding sheet 301, DBC component 102), preventing solder joint cracking and thereby improving overall reliability.

[0028] Furthermore, such as Figures 1 to 5 As shown, the gaps between the chip 101, the DBC component 102 and the first thermally conductive module 2 and the second thermally conductive module 3 are encapsulated with thermally conductive epoxy potting compound.

[0029] Thermally conductive epoxy potting compound fills the gap between chip 101 and DBC component 102, thereby ensuring the continuity of the heat transfer path and completely eliminating the possibility of moisture and contaminants accumulating in the gap, thus improving the product's weather resistance.

[0030] Furthermore, such as Figures 1 to 5 As shown, the second heat collection end of the heat dissipation module 4 is a heat pipe 401.

[0031] The model of heat pipe 401 is not further limited here. The heat dissipation module 4 using heat pipe 401 can quickly guide the heat from the high heat flux density area (the surface of chip 101) to a position where there is enough space to arrange heat dissipation fins, thereby increasing the heat dissipation efficiency of the heat dissipation system.

[0032] The first heat-collecting end of the heat dissipation module 4 is not further limited here. The first heat-collecting end of the heat dissipation module 4 can use the same heat pipe 401 as the second heat-collecting end of the heat dissipation module 4. Since the first heat-conducting module 2 includes a heat dissipation substrate 201, the first heat-collecting end of the heat dissipation module 4 can be a heat-conducting plate that is attached to the heat dissipation substrate 201 and the heat dissipation module 4. In this case, the end of the second heat-collecting end 4 of the heat dissipation module used for heat transmission can be connected to the heat dissipation module 4 or to the upper surface of the heat dissipation substrate 201.

[0033] Furthermore, such as Figures 1 to 5 As shown, the two ends of the heat pipe 401 are the first end 4011 and the second end 4012, respectively.

[0034] The first end 4011 is connected to the second heat-conducting end of the first heat-conducting module 2, and the second end 4012 is connected to the plastic-encapsulated heat-conducting layer 302. The second end 4012 is located above the chip 101. The first end 4011 is the hot end of the heat pipe 401, and the second end 4012 is the cold end of the heat pipe 401. The second heat-conducting end of the first heat-conducting module 2 is the upper surface of the heat dissipation substrate 201. At this time, this structure saves the surface space of the chip 101, and also allows the heat dissipated by the first heat-conducting module 2 to be directly conducted to the heat dissipation substrate 201, which is not in direct contact with the chip 101, thereby greatly reducing the heat accumulated on the chip 101 and increasing the working efficiency of the chip 101.

[0035] Furthermore, such as Figures 1 to 5 As shown, the first end (4011) and the second end (4012) are staggered in the vertical direction. The top view of the staggered heat pipes 401 is serpentine, and the area below the first end 4011 or the second end 4012 of any heat pipe 401 is empty. At this time, various structures can be added below, so that the heat dissipation structure described in this application can not only fully remove the heat from the upper surface of the chip 101, but also save a lot of installation space, providing support for the subsequent addition or removal of equipment.

[0036] Furthermore, this embodiment is not shown in the accompanying drawings. The heat dissipation module 4 is a water-cooled radiator, which includes a cold plate, cooling pipes, a liquid storage tank, and a water pump.

[0037] The cold plate is connected to the first heat collection end and the second heat collection end.

[0038] The wall of the cooling pipe is in contact with the cold plate, the inlet of the cooling pipe is connected to the outlet of the water pump, and the outlet of the cooling pipe is connected to the storage tank.

[0039] The inlet of the water pump is connected to the storage tank, and the water pump pumps the cooling medium in the storage tank into the cooling pipe.

[0040] The cooling medium pumped by the water pump is not further limited here. The water pump can pump cooling media such as deionized water, fluorinated liquid and ethylene glycol aqueous solution. The heat dissipation module 4 utilizes the high specific heat capacity and forced convection of the cooling medium to continuously and massively remove heat, keeping the temperature of chip 101 at a low level, thereby releasing the maximum performance potential of chip 101.

[0041] The heat dissipation method of the heat dissipation structure is as follows: S1, the heat emitted from the lower surface of the chip 101 is dissipated through “chip 101-DBC component 102-first heat conduction module 2-heat dissipation module 4”.

[0042] The heat emitted from the upper surface of the chip 101 is dissipated through the “chip 101-bonding sheet 301-molded thermal conductive layer 302-second thermal conductive module 3-heat dissipation module 4”.

[0043] S2, the heat dissipation module 4 removes the heat collected by the first heat collection end and the second heat collection end.

[0044] In summary, the heat dissipation system utilizes the bonding sheet 301 and the plastic encapsulation thermal conductive layer 302 to conduct heat from the upper surface of the chip 101 to the heat dissipation module 4, thereby making the chip 101 more secure and providing two heat dissipation channels on the upper and lower surfaces, thus solving the problem of low heat dissipation efficiency of the power module 1 in the prior art.

[0045] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A high-efficiency heat dissipation structure for a power module, characterized by: The power module (1), the first heat conduction module (2), the second heat conduction module (3) and the heat dissipation module (4) are included. The power module (1) includes a chip (101) and a DBC assembly (102), the chip (101) is welded above the DBC assembly (102), and the chip (101) and the DBC assembly (102) have a solder layer for transferring heat. The first heat conduction end of the first heat conduction module (2) is connected with the heat dissipation end of the DBC assembly (102), and the heat dissipation end of the first heat conduction module (2) is connected with the first heat collecting end of the heat dissipation module (4). The second heat conduction module (3) includes a bonding sheet (301) and a plastic sealing heat conduction layer (302), the two ends of the bonding sheet (301) are welded with the upper end face of the chip (101) and the upper end face of the DBC assembly (102) respectively, the plastic sealing heat conduction layer (302) is located above the chip (101), and the plastic sealing heat conduction layer (302) plastic seals the chip (101) and the bonding sheet (301), and the plastic sealing heat conduction layer (302) is connected with the second heat collecting end of the heat dissipation module (4). The heat dissipation module (4) transfers the heat collected by the first heat collecting end and the second heat collecting end.

2. The heat dissipation structure according to claim 1, characterized by: The first heat conduction module (2) includes a heat dissipation substrate (201), the DBC assembly (102) is arranged on the heat conduction plate of the heat dissipation substrate (201), and the heat dissipation end of the heat dissipation substrate (201) is connected with the first heat collecting end of the heat dissipation module (4).

3. The heat dissipation structure according to claim 1, characterized by: The plastic sealing material of the plastic sealing heat conduction layer (302) is heat conductive epoxy potting adhesive.

4. The heat dissipation structure according to claim 3, characterized by: The gap between the chip (101), the DBC assembly (102) and the first heat conduction module (2) and the second heat conduction module (3) is plastic sealed by heat conductive epoxy potting adhesive.

5. The heat dissipation structure according to claim 1, characterized by: The second heat collecting end of the heat dissipation module (4) is a heat pipe (401).

6. The heat dissipation structure according to claim 5, characterized by: The two ends of the heat pipe (401) are a first end (4011) and a second end (4012) respectively. The first end (4011) is connected with the second heat conduction end of the first heat conduction module (2), the second end (4012) is connected with the plastic sealing heat conduction layer (302), and the second end (4012) is located above the chip (101).

7. The heat dissipation structure according to claim 5, characterized by: The first end (4011) and the second end (4012) are arranged in a staggered manner in the vertical direction.

8. The heat dissipation structure of claim 1, wherein: The heat dissipation module (4) is a water-cooled radiator, and the water-cooled radiator includes a cold plate, a cooling pipe, a liquid storage tank and a water pump. The cold plate collects the heat collected by the first heat collecting end and the second heat collecting end. The pipe wall of the cooling pipe is attached to the cold plate, the inlet of the cooling pipe is communicated with the outlet of the water pump, and the outlet of the cooling pipe is communicated with the liquid storage tank. The inlet of the water pump is communicated with the liquid storage tank, and the water pump pumps the cooling medium in the liquid storage tank into the cooling pipe.

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