Heat dissipation substrate and power semiconductor module

Abstract

The utility model belongs to the field of power semiconductor module heat dissipation, and particularly discloses a heat dissipation substrate and a power semiconductor module, the heat dissipation substrate comprises a bottom plate and a plurality of columns arranged on the bottom plate in an array, the surface of one side of the bottom plate opposite to the columns is provided with a working area, the columns are provided with a plurality of groups of heat dissipation holes, and the working area is provided with a plurality of heat dissipation holes. The axes of the heat dissipation holes are parallel to the radial direction of the stand column, the axes of the multiple sets of heat dissipation holes are not parallel, and the axis of one set of heat dissipation holes is parallel to the flowing direction of a cooling medium on the bottom plate. The power semiconductor module comprises a heat dissipation substrate. By adopting the scheme of the utility model, the problems that the existing power semiconductor module only dissipates heat through the heat dissipation substrate or the heat dissipation column, the unit heat dissipation area is small, and the heat dissipation performance is difficult to adapt to the high-power semiconductor module can be solved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of power semiconductor module heat dissipation, specifically relates to the heat dissipation substrate and power semiconductor module. BACKGROUND

[0002] In new energy automobile main drive inverter, power semiconductor module (for example IGBT module, MOSFET module etc.) is one of its power inverter and carries out motor drive key spare parts, and its performance is good and directly influences the performance and life of new energy electric vehicle, and the heat dissipation of power semiconductor module has been the important factor restricting its development.

[0003] At present, power semiconductor module mainly has two kinds of heat dissipation structures, one is flat plate, and heat is dissipated by brushing heat-conducting silicone grease on the flat plate, and the other is that heat dissipation columns are arranged on the copper substrate of the power semiconductor module, and heat is dissipated by cooling medium (such as water or wind) flushing the heat dissipation columns, and compared with brushing heat-conducting silicone grease on the flat plate, the heat dissipation performance is obviously improved.

[0004] But with the increasing power of power semiconductor module and the high-speed development of SiC, GaN power chip, the application terminal environment is more and more complex, especially in high-temperature hot weather, the heat dissipation capacity of power semiconductor module is also more severe requirement, therefore, in addition to breakthrough in power packaging, optimizing the heat dissipation spare parts of power semiconductor module is also particularly important, and the existing power semiconductor module only dissipates heat through the heat dissipation substrate or the heat dissipation column, and the unit heat dissipation area is small, and the heat dissipation performance is difficult to apply to 3kV and above power semiconductor module, especially SiC, GaN high-performance power semiconductor module, and the corresponding power semiconductor module performance cannot be well matched, which seriously affects the performance and life of the power semiconductor module, and further affects the application terminal safety and reliability. UTILITY MODEL CONTENTS

[0005] In view of the deficiencies in the prior art, the utility model provides a heat dissipation substrate and a power semiconductor module to solve the problem that the existing power semiconductor module only dissipates heat through the heat dissipation substrate or the heat dissipation column, the unit heat dissipation area is small, and the heat dissipation performance is difficult to apply to the high-power semiconductor module.

[0006] According to the embodiments of the utility model, the following technical scheme is adopted:

[0007] The heat dissipation substrate comprises a bottom plate and a plurality of columns arranged in an array on the bottom plate, the surface of the bottom plate opposite to the columns is provided with a working area, a plurality of groups of heat dissipation holes are formed in the columns, the axis of the heat dissipation holes is parallel to the radial direction of the columns, the axes of the plurality of groups of heat dissipation holes are not parallel, and the axis of one group of heat dissipation holes is parallel to the flow direction of the cooling medium on the bottom plate.

[0008] Compared with the prior art, the utility model has the beneficial effects that:

[0009] In the scheme, the cooling medium can flow through the heat dissipation holes when flushing the column, the contact area of the cooling medium and the column is increased, the heat dissipation area is expanded, and the heat dissipation performance is improved.

[0010] In addition, through the design of multiple groups of axis non-parallel heat dissipation holes, the cooling medium can enter the heat dissipation holes on the column from different directions, and the cooling medium flow direction is not parallel to the heat dissipation holes, which has a certain hindering effect on the cooling medium flow, thereby prolonging the residence time of the cooling medium in the column to a certain extent, and further improving the contact effect of the column and the cooling medium and the heat dissipation performance.

[0011] Further, the single group of heat dissipation holes includes one heat dissipation hole, and the interval between the heat dissipation hole and the two side ends of the column along the axial direction of the column is 1-3mm.

[0012] Further, the single group of heat dissipation holes includes multiple heat dissipation holes distributed along the axial direction of the column or distributed along the radial direction of the column.

[0013] Further, the heat dissipation hole is open at one end away from the bottom plate.

[0014] Further, the bottom plate and the column are provided with a boss, and the boss and the working area on the bottom plate correspond.

[0015] Further, the columns of the adjacent two rows are arranged in a neat corresponding manner or an interleaved manner.

[0016] Further, the longitudinal section of the heat dissipation hole is in one or more of an oval shape, a rectangular shape and a circular shape.

[0017] Further, the longitudinal section of the heat dissipation hole is in an irregular shape.

[0018] Further, the bottom plate and the column are one or more of copper, copper alloy, aluminum and aluminum alloy, and the bottom plate and the column are integrally formed or welded.

[0019] According to the embodiment of the utility model, the following technical scheme is adopted:

[0020] The power semiconductor module comprises a heat dissipation substrate.

[0021] Compared with the prior art, the utility model has the beneficial effects that:

[0022] Through the design of the heat dissipation base plate, the heat dissipation area is increased, the performance of the power semiconductor module is improved, and the power semiconductor module has a larger power application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a front view of the embodiment 1 of the utility model.

[0024] Figure 2 is a side view of the embodiment 1 of the utility model.

[0025] Figure 3 is a bottom view of the embodiment 1 of the utility model.

[0026] Figure 4 is a front view of the embodiment 2 of the utility model.

[0027] Figure 5 is a front view of the embodiment 3 of the utility model.

[0028] Figure 6 is a bottom view of one design mode of the embodiment 4 of the utility model.

[0029] Figure 7 is a front view of the embodiment 4 of the utility model.

[0030] Figure 8 is a bottom view of one design mode of the embodiment 4 of the utility model.

[0031] In the drawing: 1, bottom plate; 2, boss; 3, column; 4, heat dissipation hole; 5, mounting hole. DETAILED DESCRIPTION

[0032] The utility model will be further explained in detail in combination with the drawings of the specification, and specific implementation modes are given.

[0033] Embodiment 1

[0034] As shown in Figure 1 , Figure 2 , Figure 3 , the heat dissipation base plate includes the bottom plate 1 and the column 3 arranged in array on the bottom plate 1, and the side surface of the bottom plate 1 away from the column 3 is provided with a work area, and the work area is the area of the electronic element of the power semiconductor template. In order to facilitate the assembly and application of the power semiconductor template, a plurality of mounting holes 5 are formed on the bottom plate 1, and the mounting hole 5 is used to connect and assemble the bottom plate 1 and other components of the power semiconductor template.

[0035] The columns 3 of the adjacent two rows are arranged in neat correspondence or staggered arrangement, Figure 3The upper columns 3 are arranged in a regular manner, and the lower five columns 3 are arranged in a staggered manner, which can be selected according to actual conditions.

[0036] The plurality of groups of heat dissipation holes 4 are arranged on the column 3, the axes of the heat dissipation holes 4 are parallel to the radial direction of the column 3, the axes of the plurality of groups of heat dissipation holes 4 are not parallel, and the axis of one group of heat dissipation holes 4 is parallel to the flow direction of the cooling medium (cooling liquid or cooling air) on the bottom plate 1. In actual application, after the bottom plate 1 is installed, the column 3 is arranged in the flow area of the cooling medium, and the column 3 is cooled by the flow of the cooling medium, and the axis of one group of heat dissipation holes 4 on the column 3 is parallel to the flow direction of the cooling medium, so that the cooling medium flows through the group of heat dissipation holes 4, and the cooling medium can enter the heat dissipation holes 4 on the column 3 from different directions through the design of the plurality of groups of heat dissipation holes 4 with non-parallel axes, and the cooling medium is further flushed from multiple directions, thereby improving the contact effect between the column 3 and the cooling medium and improving the heat dissipation performance.

[0037] In this embodiment, the longitudinal section of the heat dissipation hole 4 is a regular figure, for example, the longitudinal section of the heat dissipation hole 4 is one or more of an oval shape, a rectangular shape, and a circular shape. Figure 1 , Figure 2 For example, the longitudinal section of the heat dissipation hole 4 is an oval shape. In this embodiment, one group of heat dissipation holes 4 includes one heat dissipation hole 4. For example, two groups of heat dissipation holes 4 are arranged on the column 3, and the two heat dissipation holes 4 are arranged on the column 3, and the axes of the two heat dissipation holes 4 are perpendicular to each other.

[0038] The boss 2 is arranged between the bottom plate 1 and the column 3, the boss 2 corresponds to the working area on the bottom plate 1, the boss 2 is arranged opposite to the working area, the installation range of the column 3 is limited and positioned by the boss 2, so that the column 3 can be installed in the area opposite to the working area, and the optimal heat dissipation effect can be achieved.

[0039] In actual design, the bottom plate 1, the column 3, and the boss 2 are made of one or more of copper, copper alloy, aluminum, and aluminum alloy, and the bottom plate 1, the boss 2, and the column 3 are integrally formed or welded. In order to facilitate processing, the bottom plate 1, the column 3, and the boss 2 can be made of the same metal, for example, integrally formed by copper alloy. If the welding connection mode is used, the connection medium such as solder, solder sheet, and solder paste can be used for connection, and the welding equipment can be directly welded under the process permission.

[0040] Since the single group of heat dissipation holes 4 in the embodiment only includes one heat dissipation hole 4, in order to ensure that the heat dissipation area is as large as possible, the spacing between the two ends of the column 3 in the axial direction and the two side ends of the column 3 is 1-3 mm. In the actual design process, the thickness of the bottom plate 1 is not more than 10 mm, the height of the column 3 is 2-12 mm, the heat dissipation hole 4 is in the shape of an ellipse, the thickness of the bottom plate 1 is 4 mm, the thickness of the boss 2 is 2 mm, the height of the column 3 is 10 mm, and the design of the bottom plate 1, the boss 2 and the column 3 being integrally formed is taken as an example. Compared with the traditional design of only arranging the column 3 on the bottom plate 1 (the existing module), under the condition that the chip and the electrical structure of the power semiconductor module are the same, the cooling liquid with the same formula is used to flush the column 3 at the same flow rate, and the power semiconductor module is worked for 30 minutes, the temperature released by the power semiconductor module at different time points is shown in Table 1 below:

[0041] 0 min 5 min 10 min 15 min 20 min 25 min 30 min Prior art module 5℃ 42.3℃ 71.5℃ 90.6℃ 100.1℃ 100.7℃ 100.6℃ Example 1 7℃ 36.9℃ 60.3℃ 82.3℃ 82.5℃ 82.9℃ 82.4℃

[0042] Table 1 Comparison of power semiconductor module temperatures at different time points (temperature is chip junction temperature)

[0043] As shown in Table 1, under the same conditions, the temperature of the power semiconductor module at each time point provided by the heat dissipation substrate of the embodiment is lower than that of the existing module after the power semiconductor module starts to work, and the heat dissipation effect is better. At the same time, the thermal equilibrium is reached at least 5 minutes in advance, thereby effectively improving the reliability of the power semiconductor module. It should be noted that although the initial temperature has a small difference due to room temperature and module individual differences, etc., its influence can be ignored in the subsequent high-power working environment, and the results are reliable.

[0044] Embodiment 2

[0045] In the embodiment, the longitudinal section of the heat dissipation hole 4 is in an irregular shape, for example, the heat dissipation hole 4 is in the shape of a willow leaf as shown in Figure 4 Based on the experimental setting conditions of Embodiment 1, taking the heat dissipation hole 4 in the shape of a willow leaf as an example, a comparison experiment is added, and the experimental results are shown in Table 2 below:

[0046] 0 min 5 min 10 min 15 min 20 min 25 min 30 min Prior art module 5℃ 42.3℃ 71.5℃ 90.6℃ 100.1℃ 100.7℃ 100.6℃ Example 2 5℃ 37.3℃ 62.8℃ 84.7℃ 84.1℃ 84.5℃ 84.9℃

[0047] Table 2 Comparison of power semiconductor module temperatures at different time points (temperature is chip junction temperature)

[0048] As shown in Table 2, the heat dissipation hole 4 in the relatively irregular shape of a willow leaf basically has the same performance as the heat dissipation hole 4 in the regular shape in Embodiment 1, and also has good heat dissipation performance. In practice, the power semiconductor module can be reasonably selected according to the power performance and actual application scene.

[0049] Embodiment 3

[0050] AsFigure 5 As shown in the embodiment, the single group of heat dissipation holes 4 includes a plurality of heat dissipation holes 4 distributed axially along the column 3 (see the left side of the heat dissipation hole 4 design in Figure 5 Figure 3) or radially along the column 3 (see the right side of the heat dissipation hole 4 design in Figure 5 Figure 4). Compared with the single group of heat dissipation holes 4 including only one heat dissipation hole 4 in Embodiment 1, the design and processing difficulty of the embodiment is higher, and can be selected according to actual needs. Of course, the designs of the heat dissipation holes 4 on the plurality of columns 3 can be different, for example, the heat dissipation holes 4 on part of the columns 3 are designed with reference to Embodiment 1, and the heat dissipation holes 4 on part of the columns 3 are designed with reference to the embodiment.

[0051] Embodiment 4

[0052] As shown in Figure 6 , Figure 7 , Figure 8 the embodiment, the end of the heat dissipation hole 4 away from the bottom plate 1 is open. Two groups of heat dissipation holes 4 are provided on the column 3. Each group of heat dissipation holes 4 includes one heat dissipation hole 4. The axes of the two groups of heat dissipation holes 4 are perpendicular to each other, and the end of the heat dissipation hole 4 is open. Therefore, the end of the heat dissipation hole 4 is in the shape of a "cross" open slot (see Figure 6 Figure 5). Figure 8 Figure 6 shows that four groups of heat dissipation holes 4 are provided on the column 3, which can be selected and designed according to actual needs.

[0053] Based on the experimental setting conditions of Embodiment 1, taking the case that two groups of heat dissipation holes 4 are provided and the lower end of the heat dissipation hole 4 is open (see Figure 6 Figure 5) as an example, a comparative experiment is added, and the experimental results are shown in Table 3 below:

[0054] 0 min 5 min 10 min 15 min 20 min 25 min 30 min Prior art module 5℃ 42.3℃ 71.5℃ 90.6℃ 100.1℃ 100.7℃ 100.6℃ Example 3 3℃ 35.7℃ 66.3℃ 79.9℃ 80.4℃ 80.1℃ 80.4℃

[0055] Table 3 Comparison of power semiconductor module temperatures at different time points (temperature is chip junction temperature)

[0056] As shown in Table 3, the heat dissipation substrate provided in the embodiment has a lower temperature at each time point under the same conditions than the existing module, and has a better heat dissipation effect. At the same time, the thermal equilibrium is reached at least 5 minutes in advance, effectively improving the reliability of the power module.

[0057] Embodiment 5

[0058] The embodiment discloses a power semiconductor module, which includes the heat dissipation substrate described in any one of Embodiments 1-4. The power semiconductor module in the embodiment can be an IGBT module, a MOSFET module, a GaN module, a SiC module, etc.

[0059] It is to be noted that the relational terms herein, such as first and second, and the like, are used solely to distinguish one from another entity or action without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0060] Finally, it should be noted that the above embodiments are merely used to illustrate the technical solutions of the present application, rather than limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and all modifications and equivalent replacements should be covered in the scope of the claims of the present application.

Claims

1. A heat spreading substrate, characterized by: The bottom plate and a plurality of columns arranged in an array on the bottom plate, a working area is arranged on the side surface of the bottom plate opposite to the columns, a plurality of groups of heat dissipation holes are arranged on the columns, the axis of the heat dissipation holes is parallel to the radial direction of the columns, the axes of the plurality of groups of heat dissipation holes are not parallel, and the axis of one group of heat dissipation holes is parallel to the flow direction of the cooling medium on the bottom plate.

2. The heat dissipating substrate according to claim 1, wherein: The single group of heat dissipation holes comprises one heat dissipation hole, and the spacing between the two ends along the axial direction of the column and the two side ends of the column is 1-3 mm.

3. The heat dissipating substrate according to claim 1, wherein: The single group of heat dissipation holes comprises a plurality of heat dissipation holes distributed along the axial direction of the column or distributed along the radial direction of the column.

4. The heat dissipating substrate according to claim 2, wherein: The end of the heat dissipation hole opposite to the bottom plate is open.

5. The heat dissipating substrate of claim 1, wherein: A boss is arranged between the bottom plate and the column, and the boss corresponds to the working area on the bottom plate.

6. The heat dissipating substrate of claim 1, wherein: The columns of the two adjacent rows are arranged in a neat corresponding manner or in a staggered manner.

7. The heat dissipating substrate of claim 1, wherein: The longitudinal section of the heat dissipation hole is in one or more of an oval shape, a rectangular shape and a circular shape.

8. The heat dissipating substrate of claim 1, wherein: The longitudinal section of the heat dissipation hole is in an irregular shape.

9. Power semiconductor module, characterized by: The heat dissipation substrate comprises the heat dissipation substrate according to any one of claims 1-8.

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