A power semiconductor assembly

Abstract

The utility model discloses a kind of power semiconductor assemblies. Including at least one power semiconductor device and the integrated heat sink of heat connection with it;Integrated heat sink includes the metal substrate with mounting surface, multiple heat pipe units and fin heat exchange unit, each heat pipe unit includes at least part integrated in metal substrate Evaporation pipe and condensing pipe, which is communicated with evaporation pipe and extends to the outside of metal substrate, fin heat exchange unit is sleeved on the periphery of condensing pipe and is hotly connected with condensing pipe.The structure will device installation area, substrate heat conduction structure and heat pipe heat absorption structure be integrated arrangement, so that device heat can be cooperated by metal substrate and heat pipe unit Export, and dissipate outward through condensing pipe and fin heat exchange unit, to reduce the overall thermal resistance of power semiconductor assembly, improve the temperature distribution of installation area, improve heat dissipation capacity and operating stability.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor heat dissipation technology, and specifically to a power semiconductor component. Background Technology

[0002] With the development of power electronics technology, power semiconductor devices are widely used in rail transit, electric vehicles, industrial frequency converters, grid converters, energy storage devices, and high-power power supplies. Power semiconductor devices are characterized by high power density and concentrated heat flux density during operation. Their chip functional areas continuously generate heat during conduction and switching. If the heat cannot be dissipated in time, it can easily cause problems such as increased junction temperature, increased thermal stress, operating point drift, and decreased device reliability.

[0003] In existing power semiconductor heat dissipation structures, a common approach is to mount the device on a metal heat sink or a standard finned heat sink. Heat is first diffused through the base and then dissipated outwards via an air-cooling structure. Alternatively, heat pipes can be installed separately within the heat sink substrate to enhance long-distance heat transfer. While these solutions can meet heat dissipation requirements to some extent, they still have some shortcomings when applied to power semiconductor devices, where local heat flux density is high and heat generation is concentrated in the chip's functional areas. First, heat typically needs to diffuse laterally across a thicker substrate before coupling to the heat dissipation enhancement structure, resulting in limited heat extraction efficiency at local hot spots. Second, the structural matching between the device mounting surface, the substrate heat conductor, and the heat pipe evaporation section is not high, leading to significant interfacial thermal resistance, diffusion thermal resistance, and local temperature differences. Third, the synergy between the condensation and heat release structure and the air-cooling structure is limited, affecting overall heat dissipation performance.

[0004] Therefore, a new type of power semiconductor component is needed to achieve the coordinated design of device mounting structure, substrate thermal conductivity structure and heat pipe phase change heat transfer structure, thereby reducing overall thermal resistance and improving temperature distribution. Utility Model Content

[0005] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a power semiconductor component that solves the technical problems of untimely heat extraction from local hot spots, high overall thermal resistance, and uneven temperature distribution in the existing power semiconductor heat dissipation structure.

[0006] To achieve the above-mentioned technical objectives, this application adopts the following technical solution: This application provides a power semiconductor component, including: At least one power semiconductor device; An integrated heat sink is thermally connected to the power semiconductor device; The integrated heat sink includes: The metal substrate has a mounting surface on one side for mounting the power semiconductor device, and a groove on the other side; Multiple heat pipe units, each heat pipe unit including an evaporator and a condenser, the evaporator being at least partially integrated in a recess within the metal substrate, the condenser communicating with the evaporator and extending to the outer side of the metal substrate away from the mounting surface; The finned heat exchange unit is fitted around the outer periphery of the condenser tube and is thermally connected to the condenser tube.

[0007] In some embodiments of this application, the evaporator tube is a flat tube with a rectangular, rounded rectangular or open rectangular cross-section, the extension direction of its flat surface is parallel to the mounting surface, and it extends along the length direction of the mounting surface; at least a portion of the orthogonal projection area of ​​the evaporator tube on the mounting surface corresponds to and covers the chip functional area of ​​the power semiconductor device, and the metal substrate and the evaporator tube form a parallel heat conduction path.

[0008] In some embodiments of this application, a capillary reflux structure is provided at the bottom of the internal cavity of the flat tube, wherein the capillary reflux structure is one or more of copper fiber capillary core, sintered capillary core, and grooved capillary core.

[0009] In some embodiments of this application, the overall outline of the capillary reflux structure is U-shaped, the capillary reflux structure is in close contact with the bottom surface and inner wall surface of the flat tube, and its two ends extend towards the condenser tube.

[0010] In some embodiments of this application, a low thermal resistance connection structure is provided between the metal substrate and the wall of the evaporation tube. The low thermal resistance connection structure is one or more of the following: a brazing layer, a diffusion solder layer, a thermally conductive interface layer, or a metallurgical bonding layer.

[0011] In some embodiments of this application, an electrically insulating and thermally conductive layer is provided on the mounting surface, and the electrically insulating and thermally conductive layer is sandwiched between the power semiconductor device and the metal substrate.

[0012] In some embodiments of this application, there are multiple heat pipe units, and the evaporation tubes of each heat pipe unit are arranged parallel to each other and spaced apart within the metal substrate. The orthographic projection area of ​​each evaporation tube on the mounting surface corresponds to and covers the chip functional area of ​​one of the power semiconductor devices.

[0013] In some embodiments of this application, the heat pipe unit is a gravity heat pipe, and the heat pipe unit is inclined at an angle of 3° to 10° relative to the horizontal plane.

[0014] In some embodiments of this application, the condenser tube comprises multiple circular tubes, and the finned heat exchange unit comprises multiple parallel-arranged metal fins.

[0015] In some embodiments of this application, the metal substrate, the evaporator tube, and the mounting surface are formed as an integrated heat-absorbing component; the thickness of the metal substrate is greater than the thickness of the evaporator tube, and there is a preset thermal conductivity distance between the bottom surface of the evaporator tube and the mounting surface, the preset thermal conductivity distance being less than one-third of the thickness of the metal substrate.

[0016] Compared with the prior art, the beneficial technical effects of the technical solution provided in this application include: By integrating the evaporator tube at least partially into the metal substrate, the heat generated by the power semiconductor device can be directly coupled into the heat pipe unit in the area near the mounting surface, and then continue to be conducted through the metal substrate, thus forming an integrated heat dissipation path that combines substrate heat conduction and heat pipe heat transfer. After being absorbed by the evaporator tube, the heat is transferred to the condenser tube extending to the outside of the substrate and dissipated outward with the help of the finned heat exchange unit. This helps to reduce the thermal resistance of the power semiconductor component, improve the temperature distribution, and enhance the heat dissipation stability. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the embodiments will be briefly described below: Figure 1 This is a front view of a power semiconductor component according to an embodiment of this application; Figure 2 This is a side view of a power semiconductor component according to an embodiment of this application; Figure 3 This is a top view of a power semiconductor component according to an embodiment of this application; Figure 4 This is a schematic diagram of the structure of another power semiconductor component in the embodiments of this application.

[0018] Figure label: 1-Power semiconductor devices; 2-Integrated radiator, 21-Metal substrate, 22-Heat pipe unit, 221-Evaporator tube, 222-Condenser tube, 223-Capillary reflux structure, 23-Finned heat exchange unit, 231-Metal fins. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0020] Those skilled in the art will understand that, in this specification, the term "comprising" is an open-ended expression, meaning that the stated feature is present but other features are excluded. Directional terms such as "upper," "lower," "left," and "right" refer to exemplary directions based on the accompanying drawings. Features specified as "first" or "second" implicitly include one or more of that feature. Singular expressions can also be used in plural forms. "Multiple" means two or more. The terms "installed," "connected," and "linked" can refer to a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection via an intermediate medium, and it can be a connection within two components. Furthermore, "linked" can include wireless connections.

[0021] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a power semiconductor component that solves the technical problems of untimely heat extraction from local hot spots, high overall thermal resistance, and uneven temperature distribution in the existing power semiconductor heat dissipation structure.

[0022] To achieve the above-mentioned technical objectives, this application adopts the following technical solution: This embodiment provides a power semiconductor component, such as... Figures 1 to 4 As shown, it includes at least one power semiconductor device 1 and an integrated heat sink 2 thermally connected to the power semiconductor device 1.

[0023] The integrated heat sink 2 includes a metal substrate 21, multiple heat pipe units 22, and finned heat exchange units 23. The metal substrate 21 has a mounting surface on one side for mounting the power semiconductor device 1, and a recess on the other side. Each heat pipe unit 22 includes an evaporator 221 and a condenser 222. The evaporator 221 is at least partially integrated into the recess within the metal substrate 21. The condenser 222 communicates internally with the evaporator 221 and extends outward from the side of the metal substrate 21 away from the mounting surface. The finned heat exchange units 23 are fitted around the condenser 222 and maintain thermal connection with it, forming an air-side heat dissipation structure.

[0024] The metal substrate 21 can be made of a metal material with good thermal conductivity, such as copper, aluminum, or copper-aluminum composite material. The evaporator tube 221 can be embedded inside the metal substrate 21, or it can be partially buried and tightly thermally coupled to the metal substrate 21 through a low thermal resistance connection structure. The condenser tube 222 is located on the outer side of the metal substrate 21, facilitating the arrangement of larger finned heat exchange units 23, thereby increasing the heat dissipation area. Multiple heat pipe units 22 can be distributed along the width or length of the metal substrate 21 to accommodate different numbers and arrangements of power semiconductor devices 1.

[0025] In this embodiment, the power semiconductor device 1 is fixed to the mounting surface, and the heat generated during its operation is introduced into the metal substrate 21 through the mounting surface. Since the evaporator tube 221 is at least partially integrated into the metal substrate 21 and arranged close to the mounting surface, heat can be directly conducted from the metal substrate 21 to the evaporator tube 221, causing the working fluid inside the evaporator tube 221 to evaporate. The vapor enters the condenser tube 222 along the flow channel formed by the connection between the evaporator tube 221 and the condenser tube 222, releases heat to the air and condenses at the finned heat exchange unit 23 on the outer periphery of the condenser tube 222, and the condensed working fluid flows back to the evaporator tube 221, forming a circulating heat transfer. At the same time, the metal substrate 21 itself also undertakes a certain thermal conduction function, forming a heat dissipation path combined with the heat pipe heat transfer.

[0026] With the above structure, the heat of the device can be quickly introduced into the heat pipe phase change heat transfer path in the area near the mounting surface, and further discharged through the condenser tube 222 and finned heat exchange unit 23, which helps to reduce the thermal resistance of the power semiconductor component, improve the temperature distribution in the mounting area, and improve the heat dissipation stability.

[0027] In this embodiment, the evaporator tube 221 is a flat tube with a rectangular, rounded rectangular, or open rectangular cross-section. The extension direction of its flat surface is parallel to the mounting surface, and it extends along the length direction of the mounting surface. At least a portion of the orthogonal projection area of ​​the evaporator tube 221 on the mounting surface corresponds to and covers the chip functional area of ​​the power semiconductor device 1. The metal substrate 21 and the evaporator tube 221 form a parallel heat conduction path.

[0028] The flat tube arrangement allows the side of the evaporator tube 221 closest to the mounting surface to have a larger heat-receiving area, enabling a high degree of area correspondence with the chip functional area of ​​the power semiconductor device 1. The chip functional area refers to the equivalent projection area of ​​the chip or main heat-generating unit inside the power semiconductor device 1 onto the mounting surface. By aligning the projected area of ​​the evaporator tube 221 with this area, the lateral heat transfer distance from the hot spot to the surrounding substrate can be reduced.

[0029] In this embodiment, the metal substrate 21 still performs the function of heat conduction and diffusion, while the evaporator tube 221 absorbs heat near the hot spot area, and the two together form a parallel heat conduction path. Part of the heat is diffused through the metal substrate 21 via bulk heat conduction, and the other part of the heat is rapidly coupled into the heat pipe phase change heat transfer path through the area where the evaporator tube 221 is located.

[0030] During operation in this embodiment, the heat generated by the chip's functional area enters the evaporation zone near the flat tube within a very short path, causing the working fluid to evaporate more quickly and transferring the heat to the condensation zone. Because the projection relationship between the flat tube and the chip's functional area is closer, local hotspot heat is preferentially extracted. Combined with the parallel thermal conduction effect of the metal substrate 21, hotspot suppression and temperature uniformity can be achieved.

[0031] In this embodiment, a capillary reflux structure 223 is provided at the bottom of the cavity inside the flat tube. The capillary reflux structure 223 is one or more of copper fiber capillary core, sintered capillary core, and grooved capillary core.

[0032] The capillary reflux structure 223 is located inside the flat tube near the bottom, corresponding to the region where the working fluid liquid phase preferentially refluxes and is reheated and evaporates during the operation of the heat pipe unit 22. The capillary reflux structure 223 can provide capillary force, allowing the condensed liquid working fluid to return to the evaporation zone under capillary suction, which is beneficial to maintaining the stability of the working fluid circulation even under inclined operating conditions, intermittent load conditions, or local heat flux density fluctuation conditions.

[0033] Among them, copper fiber capillary cores have good thermal conductivity and capillary reflux capacity; sintered capillary cores can form a rich microporous structure, which is suitable for improving capillary pressure difference; grooved capillary cores are easy to manufacture and have relatively controllable flow resistance. Depending on the application requirements, two or three capillary structures can also be combined to balance reflux capacity and steam flow channel space.

[0034] In this embodiment, the working fluid in the evaporation zone vaporizes after being heated and flows to the condenser tube 222. The condensed liquid working fluid returns to the bottom region of the flat tube via the capillary reflux structure 223. The capillary reflux structure 223 continuously transports the condensate back to the heated position, reducing the possibility of localized drying in the evaporation zone.

[0035] In this embodiment, the overall outline of the capillary reflux structure 223 is U-shaped. The capillary reflux structure 223 is in close contact with the bottom surface and inner wall surface of the flat tube, and its two ends extend towards the condenser tube 222.

[0036] The U-shaped capillary reflux structure 223 can form a relatively continuous reflux channel along the bottom and side walls of the flat tube. The central region can reserve a relatively smooth space for steam flow, thus taking into account both liquid phase reflux and steam transport. After extending towards the condenser tube 222 at both ends, a continuous liquid reflux path can be established between the evaporation section and the condensation section, so that the condensate can be more stably returned to the evaporation zone.

[0037] In this embodiment, the U-shaped capillary reflux structure 223 is closely fitted to the inner wall of the flat tube, which can reduce the heat transfer barrier between interfaces and allow the reflux liquid to be distributed in the area close to the heated wall. The steam can flow more smoothly in the cavity in the middle of the flat tube and in the channel communicating with the condenser tube 222.

[0038] After the working fluid evaporates in the evaporation zone, it forms steam, which moves towards the condensation zone. The condensed liquid returns along the reflux paths formed on both sides and the bottom of the U-shaped capillary reflux structure 223. Since the U-shaped structure covers both the bottom and sidewalls, the liquid phase distribution is more continuous, which helps to keep the evaporation wall surface wet.

[0039] In this embodiment, a low thermal resistance connection structure is provided between the metal substrate 21 and the tube wall of the evaporation tube 221. The low thermal resistance connection structure is one or more of the following: a brazing layer, a diffusion solder layer, a thermally conductive interface layer, or a metallurgical bonding layer.

[0040] A low thermal resistance connection structure is positioned at the interface between the outer wall of the evaporator tube 221 and the metal substrate 21. Its function is to improve interface adhesion and reduce contact gaps and interface thermal resistance. For structures where the evaporator tube 221 is embedded in the metal substrate 21, brazing material can be filled between the outer wall of the evaporator tube 221 and the groove of the metal substrate 21 to complete the connection. For prefabricated assembly structures, diffusion welding or metallurgical bonding methods can be used to form a more stable thermal connection interface.

[0041] In this embodiment, if the low thermal resistance connection structure is a brazing layer, the brazing filler metal can be melted and wetted on both sides of the contact surface by heating after the evaporator tube 221 is assembled in place, and a continuous low thermal resistance connection structure can be formed after cooling. If a diffusion solder layer is used, atomic diffusion connection of the material interface can be achieved under certain temperature and pressure conditions. The thermally conductive interface layer can also be made of a high thermal conductivity interface material suitable for long-term service to meet the assembly process requirements.

[0042] The heat generated by the power semiconductor device 1 is transferred to the metal substrate 21 via the mounting surface, and then needs to cross the interface between the substrate and the evaporation tube 221 to enter the evaporation region. The low thermal resistance connection structure reduces the interfacial thermal resistance, allowing heat to be transferred more smoothly from the metal substrate 21 to the evaporation tube 221.

[0043] In this embodiment, an electrically insulating and thermally conductive layer is provided on the mounting surface, and the electrically insulating and thermally conductive layer is sandwiched between the power semiconductor device 1 and the metal substrate 21.

[0044] The electrically insulating and thermally conductive layer can be made of thermally conductive insulating sheet, ceramic insulating layer, or other insulating and thermally conductive materials suitable for mounting power semiconductor devices. On the one hand, it meets the electrical insulation requirements between the power semiconductor device 1 and the metal substrate 21, and on the other hand, it provides a low thermal resistance path, allowing the heat generated by the device to continue to be transferred to the metal substrate 21.

[0045] In this embodiment, the electrically insulating and thermally conductive layer can cover the mounting surface or be disposed only in the corresponding area of ​​the power semiconductor device 1. Its thickness can be determined comprehensively based on the withstand voltage requirements and thermal conductivity requirements. During actual assembly, the power semiconductor device 1 is press-fitted or fixed onto the electrically insulating and thermally conductive layer, which then forms a tight bond with the metal substrate 21.

[0046] The heat generated during device operation first passes through the electrically insulating and thermally conductive layer, and then enters the heat dissipation structure formed by the coupling of the metal substrate 21 and the evaporation tube 221. Because the electrically insulating and thermally conductive layer has the dual functions of thermal conduction and insulation, it can maintain the continuity of the heat dissipation channel while ensuring electrical safety.

[0047] In this embodiment, there are multiple heat pipe units 22. The evaporation tubes 221 of each heat pipe unit 22 are arranged parallel to each other and spaced apart in the metal substrate 21. The orthographic projection area of ​​each evaporation tube 221 on the mounting surface corresponds to the chip functional area of ​​a power semiconductor device 1.

[0048] In multi-device applications, multiple power semiconductor devices 1 can be arranged in an array along the length or width of the metal substrate 21. Correspondingly, multiple evaporation tubes 221 can be arranged in a zoned and matched manner according to the device positions, so that each device or the main heat-generating area inside each device has a corresponding evaporation and heat absorption channel. The spacing between the evaporation tubes 221 can take into account the substrate structural strength, heat diffusion space, and the arrangement density between heat pipe units 22.

[0049] In this embodiment, the finned heat exchange unit 23 is an integral unit, with the condenser tubes 222 passing through it. After the evaporator tubes 221 are arranged in parallel, multiple condenser tubes 222 can converge into the same finned heat exchange unit 23 area to form a centralized heat dissipation structure. The parallel and spaced layout facilitates processing and assembly, and also facilitates modular expansion according to the number of devices.

[0050] During operation, the chip functional area corresponding to each power semiconductor device 1 generates heat. This heat is preferentially coupled into the evaporator tube 221 arranged below or adjacent to it, and then transferred to the condensation area through the corresponding heat pipe unit 22. Since each evaporator tube 221 absorbs heat from different heat source areas, the local temperature rise caused by the superposition of multiple heat sources can be reduced.

[0051] In this embodiment, the heat pipe unit 22 is a gravity heat pipe, and the heat pipe unit 22 is inclined at an angle of 3° to 10° relative to the horizontal plane.

[0052] In this structure, the evaporator tube 221 is located at a relatively low position, and the condenser tube 222 is located at a relatively high position, allowing the condensate to flow back to the evaporation zone under gravity after releasing heat. The tilt angle can be set within the range of 3° to 10° depending on the equipment installation orientation, space conditions, and working fluid recirculation requirements. This angle range balances structural layout feasibility and gravity recirculation effect, making it suitable for the common air-cooled installation conditions of power semiconductor components.

[0053] In this embodiment, gravity reflux and capillary reflux structures can be used individually or in combination. When a capillary reflux structure 223 is provided inside the evaporator tube 221, gravity and capillary force work together to promote the reflux of the working fluid. When the heat flow is large or the installation posture fluctuates, this composite reflux mechanism is more conducive to maintaining the stable operation of the heat pipe unit 22.

[0054] After the working fluid evaporates in the evaporation zone, the steam rises to the condensation zone, releases heat, and condenses. The condensate then returns to the evaporation zone by gravity along the inner wall of the pipe or through capillary structures, thus completing the cycle. The inclined design allows the direction of liquid phase reflux to be coordinated with the structural layout.

[0055] By setting the heat pipe unit 22 as a gravity-type heat pipe and arranging it at an inclination angle of 3° to 10°, the reliability of liquid working fluid reflux can be improved, and the heat dissipation stability of the component under continuous heat load can be enhanced.

[0056] In this embodiment, the condenser tube 222 includes multiple circular tubes 222, and the finned heat exchange unit 23 includes multiple parallel metal fins 231.

[0057] The circular tube form of the condenser tube 222 facilitates manufacturing and assembly of the metal fins 231, making it suitable for forming a tube bundle-type condensation and heat dissipation structure. Multiple metal fins 231 can be arranged at intervals along the length of the condenser tube 222, achieving thermal connection with the condenser tube 222 through methods such as threading, expansion, brazing, or tight fitting, thereby increasing the air-side heat exchange area. The metal fins 231 can be made of aluminum to balance heat dissipation performance and structural weight.

[0058] In this embodiment, multiple condenser tubes 222 can be evenly passed through multiple metal fins 231 to form a stacked finned heat exchange unit 23. The channels between the metal fins 231 serve as airflow channels, through which external cooling air can undergo convective heat exchange with the condenser tubes 222 and the metal fins 231.

[0059] High-temperature steam from the evaporation zone enters the circular tube-shaped condenser 222, where it releases heat and undergoes phase change condensation at the inner wall of the condenser 222. The heat is further transferred to the metal fins 231 mounted on the outer periphery, and then carried away by the air flowing through the channels of the metal fins 231. Multiple circular tubes and multiple metal fins 231 can be combined to form a large heat dissipation area.

[0060] In this embodiment, the metal substrate 21, the evaporator tube 221 and the mounting surface are formed as an integrated heat-absorbing component; the thickness of the metal substrate 21 is greater than the thickness of the evaporator tube 221, and there is a preset thermal conduction distance L between the bottom surface of the evaporator tube 221 and the mounting surface, the preset thermal conduction distance L is less than one-third of the thickness of the metal substrate 21.

[0061] An integrated heat-absorbing component refers to a structurally tightly integrated relationship between the mounting surface, the metal substrate 21, and the evaporator tube 221, concentrating device mounting, heat diffusion, and heat pipe evaporation heat absorption within a single component. The evaporator tube 221 is not directly exposed at the mounting surface but is located at a certain depth below it, spaced apart from the mounting surface by a predetermined thermal conductivity distance L. This distance ensures sufficient mechanical strength and assembly flatness of the mounting surface while shortening the path of heat into the evaporator tube 221.

[0062] In this embodiment, the thickness of the metal substrate 21 is greater than the thickness of the evaporation tube 221, which helps to retain substrate material above and below the evaporation tube 221 to maintain structural rigidity and thermal diffusion space. The preset thermal conduction distance L is less than one-third of the thickness of the metal substrate 21, indicating that the evaporation tube 221 is arranged closer to the mounting surface, thereby strengthening the thermal coupling between the hot spot area and the evaporation area.

[0063] After the heat from the device passes through the area near the mounting surface, it only needs to travel a short preset thermal conduction distance L to reach the evaporator tube 221 and enter the phase change heat transfer path; at the same time, the substrate portion below and around the evaporator tube 221 can still play a role in auxiliary diffusion and support.

[0064] In this embodiment, a working fluid cavity is formed inside the heat pipe unit 22, and the working fluid cavity is filled with a working fluid, preferably deionized distilled water, with a filling ratio of 17 vol% to 20 vol%. Under the condition of an inclination angle of about 5°, the heat pipe unit 22 can obtain a relatively stable evaporation, condensation and reflux process.

[0065] During implementation, the working fluid is evacuated and then poured into the interconnected cavity formed by the evaporator tube 221 and the condenser tube 222. Deionized distilled water has good compatibility with copper or similar materials, making it suitable for phase change heat dissipation in the medium to low temperature range. The filling ratio is controlled within the range of 17 vol% to 20 vol%, which allows for the retention of an appropriate amount of liquid in the evaporation section and sufficient flow space in the condensation section and steam channel.

[0066] The working fluid absorbs heat and vaporizes in the evaporator tube 221. The vapor flows to the condenser tube 222, releases heat and condenses, and then flows back under gravity and capillary action. The type of working fluid and the amount of liquid charged together affect the start-up characteristics, cycle stability and heat transfer capacity.

[0067] The metal substrate 21 can be 560mm × 300mm × 23mm in size, and the evaporator tube 221 can have a cross-sectional dimension of 10mm × 20mm. Under these size conditions, it can be adapted to the mounting area of ​​high-power semiconductor devices 1, and provide space for the arrangement of multiple heat pipe units 22 and condensation heat dissipation structures.

[0068] The 560mm length can accommodate multiple power devices or corresponding modular mounting areas, the 300mm width facilitates the arrangement of parallel heat pipe units 22 and condenser tube arrays 222, and the 23mm thickness balances substrate strength, evaporator tube 221 embedding space, and heat diffusion capability. The 10mm×20mm cross-section of the evaporator tube 221 can form a sufficient heat absorption contact area below the mounting surface.

[0069] Under the above size matching relationship, the installation area, the evaporation heat absorption area and the condensation heat release area can form a more coordinated overall structure, making the path of heat transfer from the device installation area to the evaporation area and then to the condensation area clearer.

[0070] In the heat pipe unit 22, there can be 4-8 evaporator tubes 221 and 56-78 condenser tubes 222. Multiple evaporator tubes 221 and multiple condenser tubes 222 are connected to form an overall heat transfer network to meet larger heat dissipation requirements.

[0071] In implementation, the six evaporation tubes 221 can be arranged in parallel within the metal substrate 21, each corresponding to multiple device mounting positions or main heat-generating areas. The 68 condenser tubes 222 can be distributed in an array within the finned heat exchange unit 23 to increase the condensation heat dissipation area. The number of evaporation and condensation tubes can be determined comprehensively based on heat distribution, steam flux, and processing technology.

[0072] The evaporation side absorbs heat from multiple hot spots through multiple parallel evaporation tubes 221, while the condensation side diverts steam to a larger heat exchange area through a greater number of condensation tubes 222 to release heat, thereby realizing the diffusion and transfer of heat from local high heat flow areas to a large area of ​​air.

[0073] The thickness of the metal fins 231 can be 0.8 mm, and the fin pitch can be 3.4 mm. Simultaneously, by reducing the cross-sectional area of ​​the air duct, the cooling airflow velocity through the finned heat exchange unit 23 can be increased. In some applications, the airflow can be configured at approximately 450 m³ / h.

[0074] The 0.8mm fin thickness balances thermal conductivity and airflow resistance, while the 3.4mm fin pitch helps achieve a balance between heat exchange area and ventilation capacity. By optimizing the duct cross-section, the air velocity in the metal fin channel 231 can be increased, enhancing the convective heat transfer effect.

[0075] The heat released by the condenser tube 222 is first transferred to the metal fins 231, and then carried away by the air flowing through the gaps between the fins. When the cross-section of the air duct decreases, the average air velocity increases under a certain fan capacity, and the convective heat transfer coefficient on the surface of the metal fins 231 increases accordingly.

[0076] While maintaining the basic concept of the integrated heat sink 2, this heat dissipation structure is applicable not only to IGBT power semiconductor devices 1, but also to high heat flux density power semiconductor devices such as MOSFET power modules, SiC power device modules, IGCT modules, and rectifier modules.

[0077] During implementation, the local structure of the mounting surface, the corresponding position of the projection of the evaporator tube 221, and the form of the electrical insulation and heat conduction layer can be adapted according to the mounting hole position, insulation requirements, heating area position and heat flux density of different devices. However, the basic structural idea of ​​keeping the evaporation area close to the main heating area and the integrated heat sink 2 undertaking the synergistic effect of heat conduction and phase change heat transfer is still maintained.

[0078] Regardless of the specific device type, as long as there is a localized concentrated heat generation area in the device, the heat can be dissipated by setting up an evaporation heat absorption channel near that area and using the heat pipe unit 22 and the finned heat exchange unit 23.

[0079] In this embodiment, a guide air duct is provided on the outside of the finned heat exchange unit 23. The air inlet end of the guide air duct is connected to the fan mounting structure, and the air outlet end of the guide air duct extends along the arrangement direction of the metal fins 231 so that the cooling airflow flows directionally through the finned heat exchange unit 23.

[0080] The airflow guide duct can be installed around the finned heat exchange unit 23 using a shell-type structure, forming a relatively closed or semi-closed airflow channel. The air inlet end can be equipped with a flange-type or frame-type fan mounting structure for connection to an axial flow fan or centrifugal fan. The cross-section of the airflow guide duct can remain constant along the airflow direction, or it can be appropriately reduced to align with the aforementioned design concept of reducing the duct cross-sectional area.

[0081] After the airflow generated by the external fan enters the fin channel through the guide duct, it can flow more concentratedly through the distribution area of ​​the metal fins 231 and the condenser tubes 222, reducing bypass airflow and local dead zones, thereby increasing the proportion of effective heat exchange airflow.

[0082] Evaporator tube 221 and condenser tube 222 are connected by a transition section. The transition section is located between the edge of metal substrate 21 and finned heat exchange unit 23. The cross-section of the transition section can gradually change from rectangular to circular, or the transition section can be constructed as a multi-circular tube parallel connection structure.

[0083] In manufacturing, the transition connecting section can be integrally formed, welded, or formed by cavity connectors. One end of the transition connecting section is connected to the flat evaporator tube 221, and the other end is connected to multiple circular condenser tubes 222 for branching. Through gradual transition, the abrupt flow change of steam when entering the multiple condenser tubes 222 from the evaporator section can be reduced.

[0084] The steam generated in the evaporation zone flows through the flat evaporation tube 221 to the transition connecting section, where its flow direction is adjusted and split before entering multiple condenser tubes 222 for heat release and condensation. The gradual change in structure helps reduce local flow resistance and improve the uniformity of steam distribution.

[0085] This embodiment corresponds to the surface contact integrated connection method in the previous scheme. At least one large surface of the evaporator tube 221 is attached to the metal substrate 21, and the low thermal resistance connection structure is continuously arranged along the length of the evaporator tube 221. Specifically, a groove matching the shape of the evaporator tube 221 can be processed on the metal substrate 21. After the evaporator tube 221 is embedded in the groove, it is continuously filled and fixed by solder.

[0086] Compared to single-point, partial, or intermittent connection methods, this structure is more suitable for forming a continuous heat transfer interface. The evaporator tube 221 maintains a large-area contact with the metal substrate 21 along its length, which is beneficial for heat from different positions on the mounting surface to be coupled to the evaporator tube 221 more uniformly.

[0087] After heat enters the metal substrate 21 from the mounting surface, it can be continuously conducted to the evaporator tube 221 along a larger interface area, rather than being coupled only at local points or short sections, thereby reducing local heat accumulation.

[0088] By adopting a continuous surface contact connection structure along the length direction, the uniformity of thermal coupling between the evaporator tube 221 and the metal substrate 21 can be improved.

[0089] The IGBT power semiconductor device 1 is mounted on the mounting surface of the metal substrate 21. The heat generated during device operation is first transferred to the metal substrate 21 through the mounting interface and then coupled into the heat pipe unit 22 near the evaporator tube 221, which is located close to the main heat-generating area. The working fluid inside the evaporator tube 221 vaporizes upon heating and flows to the condenser tube 222, where it releases heat and condenses into the outside air in the condenser tube 222 and its surrounding finned heat exchange unit 23. The condensate returns to the evaporation zone under gravity, capillary action, or a combination of both, forming a continuous cycle. The metal substrate 21 simultaneously serves as both a heat diffuser and a structural support, thus forming an integrated heat dissipation path that combines mounting, heat conduction, phase change heat transfer, and air heat exchange.

[0090] Compared with the prior art, the beneficial technical effects of the technical solution provided in this application include: By placing the evaporative heat absorption structure close to the main heat-generating area of ​​the power semiconductor device and designing it in conjunction with the metal substrate 21, condenser tube 222, and finned heat exchange unit 23, the thermal resistance of the path from the device to the heat dissipation structure can be reduced, improving the heat extraction capability of local hot spots and the overall temperature distribution. At the same time, by utilizing the multi-heat pipe unit for zoned heat absorption, large-area heat release on the condenser side, working fluid circulation recirculation, and air-cooled enhanced structure, the heat dissipation capability, operational stability, and engineering applicability of the power semiconductor component under high heat flux density conditions can be improved.

[0091] Those skilled in the art will understand that the steps, measures, and schemes in the various operations, methods, processes, and procedures discussed in this application can be alternated, modified, rearranged, decomposed, combined, or deleted.

[0092] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Any other corresponding changes and modifications made based on the technical concept of this application should be included within the scope of protection of the claims of this application.

Claims

1. A power semiconductor component, characterized in that, include: At least one power semiconductor device; An integrated heat sink is thermally connected to the power semiconductor device; The integrated heat sink includes: The metal substrate has a mounting surface on one side for mounting the power semiconductor device, and a groove on the other side; Multiple heat pipe units, each heat pipe unit including an evaporator and a condenser, the evaporator being at least partially integrated in a recess within the metal substrate, the condenser communicating with the evaporator and extending to the outer side of the metal substrate away from the mounting surface; The finned heat exchange unit is fitted around the outer periphery of the condenser tube and is thermally connected to the condenser tube.

2. The power semiconductor component according to claim 1, characterized in that, The evaporator tube is a flat tube with a rectangular, rounded rectangular, or open rectangular cross-section. The extension direction of its flat surface is parallel to the mounting surface, and it extends along the length direction of the mounting surface. At least a portion of the evaporator tube's orthogonal projection area on the mounting surface corresponds to and covers the chip functional area of ​​the power semiconductor device. The metal substrate and the evaporator tube form a parallel heat conduction path.

3. The power semiconductor component according to claim 2, characterized in that, The bottom of the cavity inside the flat tube is provided with a capillary reflux structure, which is one or more of copper fiber capillary cores, sintered capillary cores, and grooved capillary cores.

4. The power semiconductor component according to claim 3, characterized in that, The overall outline of the capillary reflux structure is U-shaped. The capillary reflux structure is in close contact with the bottom surface and inner wall surface of the flat tube, and its two ends extend towards the condenser tube.

5. The power semiconductor component according to claim 1, characterized in that, A low thermal resistance connection structure is provided between the metal substrate and the tube wall of the evaporation tube. The low thermal resistance connection structure is one or more of the following: a brazing layer, a diffusion solder layer, a thermally conductive interface layer, or a metallurgical bonding layer.

6. The power semiconductor component according to claim 1, characterized in that, An electrically insulating and thermally conductive layer is provided on the mounting surface, and the electrically insulating and thermally conductive layer is sandwiched between the power semiconductor device and the metal substrate.

7. The power semiconductor component according to claim 1, characterized in that, The heat pipe unit comprises multiple units, and the evaporation tubes of each heat pipe unit are arranged parallel to each other and spaced apart within the metal substrate. The orthogonal projection area of ​​each evaporation tube on the mounting surface corresponds to and covers the chip functional area of ​​one of the power semiconductor devices.

8. The power semiconductor component according to claim 1, characterized in that, The heat pipe unit is a gravity heat pipe, and the heat pipe unit is inclined at an angle of 3° to 10° relative to the horizontal plane.

9. The power semiconductor component according to claim 1, characterized in that, The condenser tubes include multiple circular tubes, and the finned heat exchange unit includes multiple parallel metal fins.

10. The power semiconductor component according to claim 1, characterized in that, The metal substrate, the evaporator tube, and the mounting surface are formed as an integrated heat-absorbing component; the thickness of the metal substrate is greater than the thickness of the evaporator tube, and there is a preset thermal conductivity distance between the bottom surface of the evaporator tube and the mounting surface, the preset thermal conductivity distance being less than one-third of the thickness of the metal substrate.

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