Package structure of power device, power module and electronic device

Abstract

The utility model discloses a packaging structure of power device, power module and electronic equipment, the packaging structure of power device includes printed circuit board, and the first surface of printed circuit board is used for setting electronic component, power device, power device sets up on the second surface of printed circuit board, the potting layer, the potting layer covers the surface of power device and the second surface of printed circuit board, the shell, and the shell forms and is provided with accommodation cavity, and printed circuit board, power device and potting layer set up in the shell. The utility model solves the problem that the thermal resistance of packaging structure of power device is high and the poor problem of heat conduction performance.

Description

Technical Field

[0001] This utility model relates to the field of electronic device packaging, and more particularly to a packaging structure for a power device, a power module, and an electronic device. Background Technology

[0002] As electronic devices continue to evolve towards miniaturization and integration, the power density requirements for power devices are becoming increasingly stringent. For example, in fields such as electric vehicles and renewable energy power generation, higher power output needs to be achieved within limited space. This necessitates power device packaging structures that can dissipate heat more effectively while reducing package size to adapt to high-power-density application scenarios.

[0003] Traditional power devices (such as MOSFETs and IGBTs) generate a lot of heat during operation, so thermal management of power devices is required. Currently, most of them adopt a top heat dissipation design, which requires the installation of an additional heat sink or heat conduction through the copper layer inside the printed circuit board, which has the problems of high thermal resistance and poor thermal conductivity. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a power device packaging structure, power module and electronic device to solve the problems of high thermal resistance and poor thermal conductivity of the power device packaging structure.

[0005] The technical solution of this utility model is as follows:

[0006] A power device packaging structure, comprising:

[0007] A printed circuit board, wherein a first side of the printed circuit board is used to mount electronic components;

[0008] A power device, wherein the power device is disposed on the second side of the printed circuit board;

[0009] A potting layer that covers the surface of the power device and the second side of the printed circuit board;

[0010] The housing has a cavity, and the printed circuit board, the power device and the potting layer are disposed within the housing.

[0011] Optionally, the heating surface of the power device is disposed opposite to the second side of the printed circuit board and is attached to the potting layer.

[0012] Optionally, the potting layer is a silicone potting layer.

[0013] Optionally, the thermal conductivity of the silicone in the silicone potting layer is ≥0.5W / m·K, the insulating withstand voltage of the silicone is ≥3000V AC, and the hardness range of the cured silicone is Shore A 30-60.

[0014] Optionally, the outer casing is a metal casing.

[0015] Optionally, the side of the outer shell that is in contact with the potting layer is a plane.

[0016] Optionally, the side of the outer shell that is in contact with the potting layer is a grooved surface.

[0017] This utility model also proposes a power module, including the packaging structure of the power device as described above.

[0018] This invention also proposes an electronic device, including the power module described above.

[0019] This invention provides a power device encapsulation structure comprising a printed circuit board (PCB), a power device, a potting layer, and a housing. The first side of the PCB is used to house electronic components; the power device is disposed on the second side of the PCB; the potting layer covers the surface of the power device and the second side of the PCB; and the housing forms an accommodating cavity within which the PCB, power device, and potting layer are housed. By placing the power device and electronic components on different sides of the PCB, this invention increases the heat dissipation space for the power device, allowing it to conduct heat directly through the potting layer, reducing the impact of electronic components on heat conduction, and preventing the electronic components from being affected by the heat dissipated by the power device. Furthermore, covering the power device with the potting layer allows the power device to dissipate heat through the potting layer. This enhances the thermal conductivity of the power device's encapsulation structure. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 This is a functional module schematic diagram of an embodiment of the packaging structure of the power device of this utility model.

[0022] Explanation of reference numerals in the attached figures: 10, printed circuit board; 20, power device; 30, potting layer; 40, housing. Detailed Implementation

[0023] To make the objectives, technical solutions, and effects of this utility model clearer and more explicit, the present utility model will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0024] In the implementation methods and claims, unless otherwise specified in the text, the terms "a," "an," "the," and "the" may also include plural forms. If the embodiments of this utility model involve descriptions of "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0025] It should be further understood that the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when an element is referred to as "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements present. Furthermore, "connected" or "coupled" as used herein can include wireless connections or wireless coupling. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.

[0026] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0027] Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0028] As electronic devices continue to evolve towards miniaturization and integration, the power density requirements for power devices are becoming increasingly stringent. For example, in fields such as electric vehicles and renewable energy power generation, higher power output needs to be achieved within limited space. This necessitates power device packaging structures that can dissipate heat more effectively while reducing package size to adapt to high-power-density application scenarios.

[0029] Traditional power devices (such as MOSFETs and IGBTs) generate a lot of heat during operation, so thermal management of power devices is required. Currently, most of them adopt a top heat dissipation design, which requires the installation of an additional heat sink or heat conduction through the copper layer inside the printed circuit board, which has the problems of high thermal resistance and poor thermal conductivity.

[0030] To address the aforementioned problems, this invention proposes a packaging structure for power devices.

[0031] Reference Figure 1 In one embodiment, the package structure of the power device 20 includes:

[0032] Printed circuit board 10, the first side of which is used to mount electronic components;

[0033] Power device 20, wherein the power device 20 is disposed on the second surface of the printed circuit board 10;

[0034] Encapsulation layer 30, which covers the surface of the power device 20 and the second side of the printed circuit board 10;

[0035] The housing 40 has a cavity, and the printed circuit board 10, the power device 20 and the potting layer 30 are disposed inside the housing 40.

[0036] In this embodiment, the printed circuit board 10 (PCB) is a basic component used for mechanical support and connection of electronic components. Various electronic components (such as resistors, capacitors, transformers, and integrated circuits) are connected by printing conductive lines on insulating material to form a complete circuit. This design places the electronic components on the first surface of the PCB 10 and the power device 20 on the second surface, increasing the heat dissipation space for the power device 20. This allows the power device 20 to directly conduct heat through the potting layer 30, reducing the impact of electronic components on heat conduction and preventing the electronic components from being affected by the heat dissipated by the power device 20, thus avoiding malfunction. The potting layer 30 can be made of thermally conductive and insulating materials, such as silicone, plastic, or ceramic. Covering the surface of the power device 20 and the second surface of the PCB 10 with the potting layer 30 allows the power device 20 to dissipate heat to the housing through the potting layer 30, completing heat dissipation. The potting layer 30 also provides insulation protection. Therefore, the packaging structure of the power device 20 in this design does not require additional heat dissipation devices, simplifying assembly and reducing production costs. The housing can be used to fix the positional relationship of the printed circuit board 10, ensuring safety and stability inside the cavity formed by the housing. When the packaging structure of the power device 20 is working, the positional relationship of the circuit board will not change, and external gas or objects cannot fall on the circuit board and affect the operation of the electronic components on the circuit board. The housing also has a protective function for the outside of the packaging structure of the power device 20. The housing mainly has a better load-bearing capacity for external forces due to the uniform distribution of mid-surface stress along the thickness.

[0037] The packaging structure of the power device 20 in this embodiment can be used in scenarios such as power modules, electric vehicle inverters, and renewable energy converters.

[0038] This invention provides a package structure for a power device 20, comprising a printed circuit board 10, a power device 20, a potting layer 30, and a housing 40. The first side of the printed circuit board 10 is used to house electronic components; the power device 20 is disposed on the second side of the printed circuit board 10; the potting layer 30 covers the surface of the power device 20 and the second side of the printed circuit board 10; the housing 40 has a cavity within which the printed circuit board 10, power device 20, and potting layer 30 are housed. By placing the power device 20 and electronic components on different sides of the printed circuit board 10, this invention increases the heat dissipation space of the power device 20, allowing it to conduct heat directly through the potting layer 30, reducing the impact of electronic components on heat conduction, and preventing the electronic components from being affected by the heat dissipated by the power device 20. Furthermore, covering the power device 20 with the potting layer 30 allows the power device 20 to dissipate heat through the potting layer 30. This enhances the thermal conductivity of the package structure of the power device 20.

[0039] Reference Figure 1 In one embodiment, the heating surface of the power device 20 is disposed opposite to the second surface of the printed circuit board 10 and is attached to the potting layer 30.

[0040] In this embodiment, the heating surface of the power device 20 is the main heat dissipation surface. By positioning the heating surface of the power device 20 against the second surface away from the printed circuit board 10, the heat mainly dissipated by the power device 20 can be prevented from being transferred to the printed circuit board 10, thereby affecting the normal operation of the electronic components on the printed circuit board 10. Furthermore, by attaching the heating surface of the power device 20 to the potting layer 30, the heat dissipation area can be increased, resulting in better heat dissipation.

[0041] In one embodiment, the potting layer is a silicone potting layer.

[0042] In this embodiment, the potting layer is made of silicone material. Silicone has high electrical insulation properties, effectively preventing current leakage and short circuits, protecting the safety of internal electronic components. Silicone can maintain its physical and chemical properties over a wide temperature range, typically withstanding temperature changes from -60°C to 200°C, making it suitable for both high and low temperature environments. Silicone has good resistance to many chemicals (such as water, oil, acids, and alkalis), protecting electronic components in harsh environments. Silicone has good flexibility and elasticity, accommodating thermal expansion and contraction, reducing stress caused by temperature changes, thereby improving the reliability of the encapsulation. Before curing, silicone has good flowability, fully filling complex shapes and gaps to ensure comprehensive coverage and protection. Furthermore, using silicone can solve the electrical insulation problem between power devices and the metal casing; and silicone has low thermal resistance, allowing heat to be quickly conducted to the metal casing, resulting in low temperature rise of the power devices.

[0043] Furthermore, in one embodiment, the thermal conductivity of the silicone in the silicone potting layer is ≥0.5W / m·K, the insulating withstand voltage of the silicone is ≥3000V AC, and the hardness range of the cured silicone is Shore A30-60.

[0044] In this embodiment, the silicone potting layer, with a thermal conductivity ≥0.5 W / m·K, effectively conducts heat, rapidly transferring the heat generated by electronic components to the heat sink or external environment, reducing the operating temperature of the components and preventing overheating. A thermal conductivity ≥0.5 W / m·K means that under stable heat transfer conditions, for every meter of this material with a surface temperature difference of 1 K, the heat transferred per second through one square meter of area is greater than or equal to 0.5 watts. Silicone with an insulation withstand voltage ≥3000V AC effectively prevents current leakage and short circuits, ensuring safe operation of equipment in high-voltage environments and protecting users and equipment. An insulation withstand voltage ≥3000V AC indicates that the silicone's insulation performance can withstand at least 3000 volts of AC voltage. A Shore A hardness range of 30-60 gives the silicone good flexibility and elasticity, allowing it to adapt to thermal expansion and contraction, reducing stress caused by temperature changes and lowering the risk of cracking in the encapsulation layer. Shore A represents the A scale of the Shore hardness tester.

[0045] In one embodiment, the outer casing is a metal casing.

[0046] In this embodiment, the casing can be made of metal materials (such as aluminum, copper, etc.). Metal materials have high thermal conductivity, which can effectively dissipate the heat generated by the power device during operation, thereby improving the heat dissipation performance of the power device, reducing the operating temperature, and extending the service life of the power device. Metal casings typically have high mechanical strength and impact resistance, providing good protection against external physical damage. Metal casings can effectively shield electromagnetic interference, reducing the impact of external electromagnetic waves on device performance, and also preventing electromagnetic radiation generated by the device from interfering with other surrounding equipment. Metal casings provide good dustproof, waterproof, and corrosion-resistant properties, protecting internal electronic components from environmental factors. Metal materials typically have high temperature resistance, maintaining stable performance in high-temperature environments.

[0047] In one embodiment, the side of the outer shell that is in contact with the potting layer is a plane.

[0048] In this embodiment, the bonding surface between the outer shell and the potting layer is planar, which simplifies the manufacturing process and provides good sealing performance. The planar bonding surface provides a uniform pressure distribution during potting, allowing the potting material to better fill the gap between the outer shell and the internal components, forming a continuous and complete sealing layer. The planar bonding surface provides a large contact area, facilitating heat transfer from the internal components to the outer shell and then dissipating it into the surrounding environment. This large-area heat conduction path makes heat dissipation performance more stable, effectively reducing the temperature inside the package structure and improving component efficiency and lifespan. The relatively uniform thermal resistance distribution of the planar bonding surface avoids the problem of excessively high or low local thermal resistance caused by microstructures.

[0049] In one embodiment, the side of the outer shell that adheres to the potting layer is a grooved surface.

[0050] In this embodiment, the bonding surface between the outer shell and the potting layer is a grooved surface. The grooved microstructure can form a mechanical lock with the potting material, increasing the bonding force between the outer shell and the potting layer. When the package structure is subjected to external forces, this mechanical lock can effectively resist shear and tensile forces, preventing the potting layer from separating from the outer shell and improving the overall strength and reliability of the package structure. The grooved microstructure increases the surface area of ​​the bonding surface, thereby increasing the heat dissipation area. This helps to enhance the ability of heat to be transferred from internal components to the outer shell, improving heat dissipation efficiency. Especially for the packaging of high-power components, the grooved microstructure can effectively reduce the operating temperature of the components, improving their performance and reliability. The grooved microstructure can form microchannels, promoting the flow of air or coolant on the bonding surface, further enhancing the heat dissipation effect.

[0051] This utility model also proposes a power supply module.

[0052] In one embodiment, the power module includes the package structure of the power device as described above.

[0053] In this embodiment, it can be understood that since the power module of this utility model uses the above-mentioned power device packaging structure, the embodiments of the power module of this utility model include all the technical solutions of all embodiments of the above-mentioned power device packaging structure, and the technical effects achieved are exactly the same, so they will not be repeated here.

[0054] Specifically, when used in the packaging of power modules for electric vehicles, power devices (such as SiCMOSFETs) are mounted on the bottom pads of a printed circuit board (such as FR4PCB); high thermal conductivity silicone (thermal conductivity 1.5W / m·K) is used for potting, and after vacuum degassing, it is cured at 100℃ for 30 hours; the potted module is then pressed onto an aluminum alloy shell (surface roughness Ra≤1.6μm), with a measured thermal resistance of 1.8℃ / W and a withstand voltage of 3500V AC.

[0055] When used in a 400W industrial power supply, power devices (such as SiC MOSFETs) are mounted on the bottom pads of a printed circuit board (such as an FR4PCB); high thermal conductivity silicone (thermal conductivity 0.8W / m·K) is used for potting, and after vacuum degassing, it is cured at 120℃ for 15 minutes; the potted module is then pressed onto an aluminum alloy shell (surface roughness Ra≤1.6μm), with a measured thermal resistance of 1.2℃ / W and a withstand voltage of 3500V AC.

[0056] This utility model also proposes an electronic device.

[0057] In one embodiment, the electronic device includes a power module as described above.

[0058] In this embodiment, it can be understood that since the above-mentioned power module is used in the electronic device of this utility model, the embodiments of the electronic device of this utility model include all the technical solutions of all the embodiments of the above-mentioned power module, and the technical effects achieved are exactly the same, so they will not be repeated here.

[0059] It should be understood that the application of this utility model is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A packaging structure of a power device, characterized by, include: A printed circuit board, wherein a first side of the printed circuit board is used to mount electronic components; A power device, wherein the power device is disposed on the second side of the printed circuit board; A potting layer that covers the surface of the power device and the second side of the printed circuit board; The housing has a cavity, and the printed circuit board, the power device and the potting layer are disposed within the housing.

2. The packaging structure of a power device according to Claim 1, wherein The heating surface of the power device is away from the second side of the printed circuit board and is attached to the potting layer.

3. The packaging structure of a power device according to Claim 1, wherein The potting layer is a silicone potting layer.

4. The packaging structure of a power device according to Claim 3, wherein The silicone in the silicone potting layer has a thermal conductivity ≥0.5W / m·K, an insulation withstand voltage ≥3000V AC, and a hardness range of Shore A 30-60 after curing.

5. The packaging structure of a power device according to Claim 1, wherein The outer casing is a metal casing.

6. The packaging structure of a power device according to Claim 5, wherein The side of the outer shell that is in contact with the potting layer is a flat surface.

7. The packaging structure of a power device according to Claim 5, wherein The side of the outer shell that is in contact with the potting layer is a grooved surface.

8. A power module, characterized by The package structure includes the power device as described in any one of claims 1-7.

9. An electronic device, comprising: Includes the power module as described in claim 8.

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