Heat dissipation structure and power device

Abstract

A heat dissipation structure and a power device belong to the technical field of power devices. The power device comprises a chip and a heat dissipation structure. The heat dissipation structure comprises a metal substrate and a heat dissipation back plate which are oppositely arranged, the metal substrate and the heat dissipation back plate are enclosed through an insulation sealing plate to form a sealing cavity, and a gas-liquid phase change insulation working medium is arranged in the sealing cavity. The chip is arranged on the side, away from the heat dissipation backboard, of the metal substrate. Heat generated by the chip can be directly transmitted to the metal substrate, the metal substrate transmits the heat to the gas-liquid phase change insulating working medium in the sealing cavity, the heat is transmitted to the heat dissipation back plate through the gas-liquid phase change insulating working medium, the heat dissipation back plate exchanges heat with the external environment or a heat dissipation piece, and heat dissipation of the chip is achieved. In the heat dissipation structure, as the metal heat dissipation substrate and the heat dissipation back plate are insulated and isolated through the insulating sealing plate and the gas-liquid phase change insulating working medium, an insulating layer such as a ceramic substrate does not need to be arranged between the chip and the metal substrate, the heat resistance can be reduced, and the heat dissipation efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of power devices, and in particular to a heat dissipation structure and a power device. Background Art

[0002] As power density requirements continue to increase, the heat dissipation structure has become a bottleneck for increasing the power density of devices such as module-packaged IGBTs and SiC modules, so it is necessary to improve the heat dissipation efficiency of power devices.

[0003] In existing heat dissipation solutions for shell-encapsulated or plastic-encapsulated IGBT and SiC modules, the chip is typically soldered to a double-sided copper-plated Al2O3 or Si3N4 ceramic substrate, with a copper base plate soldered to the back of the ceramic substrate. In this heat dissipation method, the ceramic substrate conducts heat from the chip to the copper base plate, which then transfers the heat to the external environment or other heat sinks via the copper base plate. The high thermal resistance between the ceramic and copper base plates severely limits the heat dissipation performance of the power device. Summary of the Invention

[0004] Based on the above-mentioned deficiencies, the present application provides a heat dissipation structure and a power device to improve the problem of low heat dissipation efficiency of the heat dissipation structure in the related art.

[0005] This application is implemented as follows:

[0006] In a first aspect, the examples of this application provide a heat dissipation structure comprising a metal substrate and a heat dissipation backplate disposed opposite each other. The metal substrate and the heat dissipation backplate are enclosed by an insulating sealing plate to form a sealed cavity, within which a gas-liquid phase-change insulating medium is disposed. The side of the metal substrate facing away from the heat dissipation backplate is electrically connected to a chip; the gas-liquid phase-change insulating medium is capable of transferring heat from the chip to the heat dissipation backplate.

[0007] In the above implementation process, the chip is directly placed on the metal substrate. Since the metal substrate and the heat dissipation backplate are enclosed by an insulating sealing plate to form a sealed chamber, and the gas-liquid phase change heat dissipation material set in the sealed chamber is an insulating medium, the metal substrate and the heat dissipation backplate can be insulated, and the ceramic substrate used to provide insulation in traditional heat dissipation structures can be omitted. When the chip is dissipated using the above heat dissipation structure, the heat generated by the chip can be directly transferred to the metal substrate, eliminating the need for multiple heat exchanges between the ceramic substrate and the metal substrate, reducing thermal resistance and thereby improving heat transfer efficiency. The heat at the metal substrate can be heat-exchanged with the gas-liquid phase change insulating medium in the sealed chamber. Through the gas-liquid phase change of the gas-liquid phase change insulating medium, the heat is transferred to the heat dissipation backplate, which is then dissipated by the heat dissipation backplate and the external environment or other heat dissipation components. In addition, when the chip is installed, the power terminals of the chip can be directly soldered to the metal substrate, eliminating the need to lead the power terminals out and solder them to an additional copper busbar. This can shorten the power terminal circuit, simplify the wiring, and improve power density.

[0008] In combination with the first aspect, in an optional implementation, the gas-liquid phase-change insulating working fluid includes ethanol or acetone.

[0009] In the above implementation process, the above-mentioned gas-liquid phase change insulating working fluid is used as a phase change heat dissipation working fluid. The liquid working fluid can absorb the heat transferred to the metal substrate and change phase to a gaseous working fluid. The gaseous working fluid can flow to the heat dissipation backplate to exchange heat with the heat dissipation backplate, release heat, and change phase to a liquid working fluid. The liquid working fluid can flow back to the metal substrate, absorb heat again and change phase, and this cycle is repeated. Through the gas-liquid phase change, efficient heat dissipation is achieved. In addition, the above-mentioned phase change working fluid has good insulation properties, whether in gas or liquid state. The probability of leakage in the heat dissipation structure is low, which can improve safety.

[0010] In combination with the first aspect, in an optional embodiment, the resistivity of the insulating sealing plate is 10 9 Ω·cm~10 16 Ω·cm.

[0011] Optionally, the insulating sealing plate is made of resin.

[0012] Optionally, the insulating sealing plate is made of epoxy resin, polyurethane resin, phenolic resin or rubber.

[0013] In the above implementation process, the resistivity of the insulating sealing plate is 10 9 Ω·cm~10 16Ω·cm, which can insulate the metal substrate from the heat sink backplane, eliminating the need for a ceramic substrate. The insulating sealing plate is made of resin, particularly epoxy, polyurethane, phenolic, or rubber. These materials not only exhibit excellent mechanical properties but also provide a strong seal, reducing the chance of gaseous fluid leakage within the sealed cavity and extending the life of the heat sink structure.

[0014] In combination with the first aspect, in an optional embodiment, a plurality of grooves are provided on a side of the metal substrate close to the heat dissipation back plate.

[0015] Optionally, the width of the groove is 10 to 1000 μm.

[0016] Optionally, the material of the metal substrate includes at least one of copper, silver or gold.

[0017] In the above implementation, multiple grooves are provided on the side of the metal substrate near the heat dissipation backplate to increase the contact area between the metal substrate and the gas-liquid phase-change insulating medium within the sealed cavity, further improving heat dissipation efficiency. Furthermore, the metal substrate is made of a high-electrical and high-thermal conductivity material such as copper, silver, or gold, which not only meets the heat transfer requirements of the heat dissipation structure but also satisfies the chip's conductive connection requirements, reducing the resistance between the chip and the metal substrate.

[0018] In combination with the first aspect, in an optional embodiment, in the sealed cavity, a wire mesh is provided on a side of the heat dissipation back plate facing the metal substrate.

[0019] Optionally, the porosity of the wire mesh is 70-90%.

[0020] In the above implementation process, a wire mesh is filled in the sealed cavity. The porous structure of the wire mesh has a certain permeability, which can promote the penetration of liquid working medium into the side of the metal substrate. In addition, the wire mesh can also promote the condensation of gaseous working medium flowing to the wire mesh into liquid working medium, further accelerating the gas-liquid phase transition rate of the working medium, thereby improving heat dissipation efficiency.

[0021] In combination with the first aspect, in an optional embodiment, in the sealed cavity, a plurality of spray nozzles are spaced apart on the side of the heat dissipation backplate facing the metal substrate, and each spray nozzle faces the metal substrate and is used to spray the liquid gas-liquid phase change insulating medium into the groove.

[0022] In the above implementation process, a spray nozzle is set in the sealed cavity near the heat dissipation backplate. The spray nozzle can spray the gas-liquid phase change insulating medium in liquid state after condensation on the heat dissipation backplate into the groove of the metal substrate, thereby accelerating the efficiency of heat exchange between the liquid insulating medium and the metal substrate, and further improving the heat dissipation efficiency.

[0023] In combination with the first aspect, in an optional implementation, the thermal conductivity of the heat dissipation backplate is not less than 10 W / (m·K).

[0024] Optionally, the heat dissipation back plate is made of metal, ceramic or resin.

[0025] Optionally, the heat dissipation backplate is made of copper.

[0026] In the above implementation process, the heat dissipation backplate adopts a high thermal conductivity material with a thermal conductivity coefficient of not less than 10W / (m·K), which can improve the heat transfer exchange efficiency between the heat dissipation backplate and the gaseous working medium in the sealed cavity, accelerate the phase transition of the gaseous working medium, and further improve the heat dissipation efficiency.

[0027] In combination with the first aspect, in an optional embodiment, a heat dissipation element is provided on a side of the heat dissipation back plate facing away from the metal substrate.

[0028] Optionally, the heat sink includes heat dissipation fins.

[0029] Optionally, the heat sink includes a liquid cooling plate.

[0030] In the above implementation process, heat dissipation components such as heat dissipation fins and liquid cooling plates are arranged on the side of the heat dissipation backplate away from the metal substrate, which can further accelerate the condensation effect of the heat dissipation backplate on the gaseous working medium, accelerate the phase change rate of the phase change working medium, and further improve the heat dissipation efficiency.

[0031] In a second aspect, an example of the present application provides a power device, comprising a chip and the heat dissipation structure provided in the first aspect. The chip is soldered to a side of a metal substrate facing away from a heat dissipation back plate.

[0032] In combination with the second aspect, in an optional implementation, the power terminal of the chip is welded to a side of the metal substrate facing away from the heat dissipation backplate.

[0033] In the above-mentioned power device, the chip can be directly soldered to the metal substrate of the heat dissipation structure, transferring heat to the metal substrate, which then transfers heat to the gas-liquid phase-change insulating medium in the sealed cavity. The gas-liquid phase-change insulating medium then exchanges heat with the heat dissipation backplate, and the heat dissipation of the chip is achieved by heat exchange between the heat dissipation backplate and the external environment or other heat dissipation components. In the above-mentioned power device, since the metal substrate and the heat dissipation backplate are insulated and isolated by the insulating sealing plate and the gas-liquid phase-change insulating medium, the metal substrate can serve as both a heat dissipation substrate and an electrical connection substrate (which can connect to the chip's power terminals, etc.), which can reduce the space occupancy of the heat dissipation structure in the power device, enable the arrangement of more chips and other power components, and thus improve the power density. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art.

[0035] Figure 1 A schematic diagram of the structure of a heat dissipation module provided for comparison technology;

[0036] Figure 2 A schematic diagram of a first heat dissipation structure provided in an embodiment of the present application;

[0037] Figure 3 A schematic diagram of a second heat dissipation structure provided in an embodiment of the present application;

[0038] Figure 4 A schematic diagram of a third heat dissipation structure provided in an embodiment of the present application;

[0039] Figure 5 A schematic diagram of the structure of a power device provided in an embodiment of the present application.

[0040] Icons: 100-heat dissipation module; 101-electronic component; 102-ceramic substrate; 103-first copper plating layer; 104-second copper plating layer; 105-copper substrate; 106-housing; 1-power device; 200-heat dissipation structure; 201-metal substrate; 202-heat dissipation back plate; 203-insulating sealing plate; 204-sealed cavity; 205-gas-liquid phase change insulating medium; 206-welding layer; 207-groove; 208-wire mesh; 209-spray nozzle; 210-heat dissipation component; 300-chip; 301-power terminal. DETAILED DESCRIPTION

[0041] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions.

[0043] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0044] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0045] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "middle", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "bottom", and "inside" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0046] See also Figure 1 In the current heat dissipation module 100, a first copper-plated layer 103 and a second copper-plated layer 104 are respectively provided on either side of a ceramic substrate 102. The first copper-plated layer 103 is used to solder the electronic component 101 to the ceramic substrate 102, and the second copper-plated layer 104 is used to solder the ceramic substrate 102 to the copper substrate 105. The back of the copper substrate 105 and the metal housing 106 form a sealed cavity, within which a gas-liquid phase change medium is disposed. Alternatively, the back of the copper substrate 105 directly dissipates heat through contact with the external environment.

[0047] Since the copper substrate 105 dissipates heat directly from the external environment or dissipates heat from the external environment through other heat sinks, in the existing heat dissipation module 100, an insulating ceramic substrate 102 needs to be provided between the electronic component 101 and the copper substrate 105 to insulate and isolate the electronic component 101 from the external environment.

[0048] When the heat dissipation module 100 is in operation, the heat generated by the electronic component 101 is transferred from the first copper-plated layer 103 to the ceramic substrate 102, then from the ceramic substrate 102 to the second copper-plated layer 104, then from the second copper-plated layer 104 to the copper substrate 105, and then from the copper substrate 105 to the gas-liquid phase change medium. The gas-liquid phase change medium transfers the heat to the metal housing 106, and the heat is dissipated by the body wall of the metal housing 106 and the outside world or other heat dissipation components. During the heat dissipation process of the heat dissipation module 100, before being transferred to the gas-liquid phase change medium, the heat is frequently transferred between the metal layer (referring to the first copper-plated layer 103, the second copper-plated layer 104, and the copper substrate 105) and the ceramic layer (referring to the ceramic substrate 102). There is a large thermal resistance between the metal layer and the ceramic layer, which affects the heat transfer and thus leads to low heat dissipation efficiency of the heat dissipation module 100.

[0049] Therefore, the present application further improves the heat dissipation mechanism, thereby improving the problem of low heat dissipation efficiency of the heat dissipation structure to a certain extent. To make the purpose, technical solution and advantages of the embodiments of the present application more clear, the technical solution of the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application.

[0050] See also Figure 2 The present embodiment provides a heat dissipation structure 200, comprising a metal substrate 201 and a heat dissipation backplate 202 disposed opposite each other. The metal substrate 201 and the heat dissipation backplate 202 are enclosed by an insulating sealing plate 203 to form a sealed cavity 204. A gas-liquid phase-change insulating medium 205 is disposed within the sealed cavity 204. The side of the metal substrate 201 facing away from the heat dissipation backplate 202 is electrically connected to the chip 300. The gas-liquid phase-change insulating medium 205 can transfer heat from the chip 300 to the heat dissipation backplate 202.

[0051] The gas-liquid phase-change insulating medium 205 is an insulating heat dissipation medium capable of undergoing a gas-liquid phase change. Within the sealed cavity 204, the heat dissipation medium includes both a gaseous insulating heat dissipation medium and a liquid insulating heat dissipation medium. Hereinafter, the liquid heat dissipation medium will be referred to as the liquid insulating heat dissipation medium, and the gaseous heat dissipation medium will be referred to as the gaseous insulating heat dissipation medium. The liquid insulating heat dissipation medium absorbs heat and undergoes a phase change to a gaseous insulating heat dissipation medium, while the gaseous insulating heat dissipation medium releases heat and undergoes a phase change to a liquid insulating heat dissipation medium.

[0052] When the heat dissipation structure 200 provided in the embodiment of the present application is used to dissipate heat from the chip 300, the heat generated by the chip 300 can be directly transferred to the metal substrate 201 without passing through a substrate made of insulating materials such as a ceramic substrate. The thermal resistance during the process of transferring the heat from the chip 300 to the metal substrate 201 is small, and the heat transfer efficiency is high. The heat transferred to the metal substrate 201 can be transferred to the liquid insulating medium in the sealed cavity 204. The liquid insulating medium absorbs the heat and undergoes a phase change to a gaseous insulating medium. The gaseous insulating medium flows to the heat dissipation backplate 202. The heat dissipation backplate 202 absorbs the heat of the gaseous insulating medium and exchanges heat with the external environment or other heat dissipating parts. The gaseous insulating medium undergoes a phase change to a liquid medium. The liquid phase change medium reabsorbs the heat from the metal substrate 201, and this cycle is repeated to achieve efficient heat dissipation of the chip 300.

[0053] Compared with the heat dissipation method of the heat dissipation module 100 in the comparative technology, when the heat of the electronic component 101 in the comparative technology is transferred to the copper substrate 105, the heat will be frequently transferred between the metal layer and the ceramic layer. However, in the heat dissipation structure 200 provided in the embodiment of the present application, when the heat of the chip 300 is transferred to the metal substrate 201, the heat will not be frequently transferred between the metal layer and the ceramic layer, thereby improving the problem of low heat transfer efficiency caused by the large thermal resistance between the metal layer and the ceramic layer.

[0054] The present application does not limit the specific material of the metal substrate 201. The metal substrate 201 needs to have good electrical conductivity and thermal conductivity. In some embodiments, the material of the metal substrate 201 can be any one of copper, silver or gold.

[0055] As an example, the metal substrate 201 may be a copper substrate.

[0056] The metal substrate 201 serves as a carrier for the chip 300 . The metal substrate 201 also needs to have a suitable thickness to support the chip 300 .

[0057] In some embodiments, see Figure 5 The chip 300 can be welded on the metal substrate 201 , and a welding layer 206 can be provided between the metal substrate 201 and the chip 300 .

[0058] Furthermore, in order to increase the contact area between the metal substrate 201 and the gas-liquid phase-change insulating medium 205 in the sealed cavity 204, in some embodiments, please continue to refer to Figure 3 , a plurality of grooves 207 may be provided on a side of the metal substrate 201 facing the heat dissipation back plate 202 .

[0059] The present application does not limit the specific size of the groove 207 . In some embodiments, the width of the groove 207 may be 10 to 1000 μm.

[0060] As an example, the width of the trench 207 may be one of 10 μm, 50 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm or 1000 μm, or a range between any two of them.

[0061] Furthermore, in some embodiments, the width of the trench 207 may be 10-100 μm.

[0062] The present application does not limit the specific arrangement of the grooves 207. In some embodiments, the grooves 207 may be arranged in an array, or the grooves 207 may be arranged in a disordered manner.

[0063] The present application does not limit the specific preparation method of the groove 207. In some embodiments, the groove 207 can be formed by laser grooving.

[0064] Alternatively, in other embodiments, a porous capillary structure may be provided on the side of the metal substrate 201 facing the heat dissipation backplate 202. This porous capillary structure provides more complete contact with the gas-liquid phase-change insulating medium, further improving heat dissipation efficiency. Furthermore, the porous capillary structure has a certain liquid absorption capacity, enabling liquid insulating phase-change medium condensed on the heat dissipation backplate 202 to be moved more quickly to the metal substrate 201.

[0065] The present application does not limit the specific preparation method of the porous capillary structure. In some embodiments, the preparation method of the porous capillary structure includes: laying a mixed powder of metal powder and a pore-forming agent on one side of the metal substrate 201, sintering the mixed powder at a suitable temperature, so that the pore-forming agent volatilizes or decomposes to leave holes in the metal matrix, thereby forming a metal porous capillary structure.

[0066] The present application does not limit the specific material of the heat dissipation back plate 202. The heat dissipation back plate 202 needs to have good heat dissipation performance and be able to dissipate heat with the external environment or other heat dissipation components.

[0067] In some embodiments, the thermal conductivity of the heat dissipation back plate 202 is not less than 10 W / (m·K).

[0068] Since the heat dissipation back plate 202 and the metal substrate 201 are insulated and isolated by the insulating sealing plate 203 and the gas-liquid phase change insulating medium, the present application does not limit whether the heat dissipation back plate 202 itself has insulation properties.

[0069] In some embodiments, the heat dissipation back plate 202 may be made of metal, ceramic, or resin materials with good heat dissipation performance.

[0070] As an example, the heat dissipation back plate 202 may be made of metal materials, including but not limited to metal iron or metal copper.

[0071] As an example, the heat dissipation back plate 202 may be made of ceramic materials, including but not limited to aluminum oxide or silicon nitride ceramics.

[0072] As an example, the heat dissipation back plate 202 may be made of a resin material, including but not limited to high-temperature resistant thermal conductive resins such as epoxy resin or polyimide resin.

[0073] The present application does not limit the specific material of the insulating sealing plate 203 . The insulating sealing plate 203 needs to have high insulation and good sealing properties to enclose the metal substrate 201 and the heat dissipation back plate 202 to form a sealed cavity 204 .

[0074] As an example, the resistivity of the insulating sealing plate 203 is 10 9 Ω·cm~10 16 Ω·cm.

[0075] As an example, the insulating sealing plate 203 is made of resin, and the resin material is in-situ molded by some curing method to form a sealed cavity 204 between the metal substrate 201 and the heat dissipation back plate 202 .

[0076] As an example, the material of the insulating sealing plate 203 includes at least one of epoxy resin, polyurethane resin, phenolic resin or rubber.

[0077] Furthermore, in some embodiments, the insulating sealing plate 203 may be sealed and connected to the metal substrate 201 and the heat dissipation back plate 202 by means of a sealant.

[0078] Furthermore, the present application does not limit the specific shape of the sealed cavity 204. As an example, the metal substrate 201 and the heat dissipation back plate 202 are both rectangular plate structures, one end of the insulating sealing plate 203 is enclosed around the four edges of the metal substrate 201, and the other end of the insulating sealing plate 203 is enclosed around the four edges of the heat dissipation back plate 202 to form a sealed cavity 204.

[0079] The present application does not limit the specific type of the gas-liquid phase-change insulating medium 205 . In some embodiments, the gas-liquid phase-change insulating medium 205 includes but is not limited to ethanol or acetone.

[0080] In some embodiments, the gas-liquid phase-change insulating medium may further include deionized water.

[0081] It is understandable that the gas-liquid phase-change insulating medium 205 will not completely fill the sealed cavity 204 , and a channel for the gaseous insulating medium and the liquid insulating medium to flow is left in the sealed cavity 204 .

[0082] In order to further accelerate the phase conversion efficiency of the gas-liquid phase-change insulating medium 205, in some embodiments, please continue to refer to Figure 3 In the sealed cavity 204 , a wire mesh 208 is provided on the side of the heat dissipation back plate 202 facing the metal substrate 201 .

[0083] A wire mesh 208 is provided at the heat dissipation back plate 202 . When the gaseous insulating working medium flows to the wire mesh 208 , the wire mesh 208 can accelerate the condensation efficiency of the gaseous insulating working medium.

[0084] The present application does not limit the specific size of the wire mesh 208. In some embodiments, the porosity of the wire mesh 208 is 70-90%, and the average pore size is 10-500 μm.

[0085] The present application does not limit the material of the wire mesh 208. In some embodiments, the wire mesh 208 may be a nylon mesh. Alternatively, in some embodiments, the wire mesh 208 may be a copper mesh, which is fixed to the heat dissipation backplate 202 and has a thickness no greater than that of the sealed cavity 204 to prevent contact between the copper mesh and the metal substrate 201.

[0086] In order to further accelerate the rate at which the liquid insulating medium flows to the metal substrate 201, in some embodiments, please continue to refer to Figure 3 In the sealed cavity 204 , a plurality of spray nozzles 209 are spaced apart on the side of the heat dissipation back plate 202 facing the metal substrate 201 , and each spray nozzle 209 faces the metal substrate 201 and is used to spray the liquid insulating medium into the groove 207 of the metal substrate 201 .

[0087] The present application does not limit the specific configuration of the spray nozzle 209. In some embodiments, a pump body is disposed at the bottom of the sealed cavity 204 and is immersed in the liquid insulating medium on the heat dissipation backplate 202. The pump body draws in the liquid insulating medium and delivers it to the nozzle, which then sprays it toward the metal substrate 201. A through hole can be provided in the heat dissipation backplate 202, and a working wiring harness of the pump body can be passed through the through hole in the heat dissipation backplate 202 to connect to an external device. The working wiring harness is sealed to the through hole to prevent the liquid insulating medium from leaking out of the through hole.

[0088] To further improve heat dissipation efficiency, in some embodiments, see Figure 4 A heat sink 210 may be provided on the side of the heat dissipation back plate 202 away from the metal substrate 201 to accelerate the heat exchange efficiency of the heat dissipation back plate 202 and improve the condensation efficiency of the liquid insulating medium.

[0089] As an example, the heat sink 210 may be a heat sink fin, a liquid cooling plate, or a fan.

[0090] Furthermore, the present invention also provides a power device 1, see Figure 5, including a chip 300 and a heat dissipation structure 200 , wherein the chip 300 is soldered to a side of a metal substrate 201 away from a heat dissipation back plate 202 .

[0091] In the power device 1 described above, since the chip 300 is directly soldered to the metal substrate 201, the heat generated by the chip 300 can be transferred to the metal substrate 201, and then transferred to the heat dissipation backplate 202 by the gas-liquid phase change insulating medium 205. The heat dissipation backplate 202 then exchanges heat with the external environment or the heat sink 210, achieving efficient heat dissipation of the chip 300. The heat dissipation structure 200 in the power device 1 has high heat dissipation efficiency and can meet the heat dissipation requirements of more chips 300, thereby increasing the power density of the power device 1.

[0092] Also, please continue reading Figure 5 The metal substrate 201 has good electrical conductivity, and the power terminal 301 of the chip 300 can be directly soldered to the metal substrate 201, shortening the line of the power terminal 301 and simplifying the wiring.

[0093] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A heat dissipation structure, characterized in that: include: A metal substrate and a heat dissipation backplate are arranged opposite to each other, and the metal substrate and the heat dissipation backplate are enclosed by an insulating sealing plate to form a sealed cavity, and a gas-liquid phase-change insulating medium is arranged in the sealed cavity; the side of the metal substrate facing away from the heat dissipation backplate is used for conductive connection with the chip; the gas-liquid phase-change insulating medium can transfer the heat of the chip to the heat dissipation backplate.

2. The heat dissipation structure according to claim 1, characterized in that: The gas-liquid phase-change insulating medium includes ethanol or acetone.

3. The heat dissipation structure according to claim 1 or 2, characterized in that: The resistivity of the insulating sealing plate is 10 9 Ω·cm~10 16 Ω·cm; Optionally, the insulating sealing plate is made of resin; Optionally, the insulating sealing plate is made of epoxy resin, polyurethane resin, phenolic resin or rubber.

4. The heat dissipation structure according to claim 1, characterized in that: A plurality of grooves are provided on a side of the metal substrate close to the heat dissipation back plate; Optionally, the width of the groove is 10 to 1000 μm; Optionally, the material of the metal substrate includes at least one of copper, silver or gold.

5. The heat dissipation structure according to claim 4, characterized in that: In the sealed cavity, a wire mesh is provided on the side of the heat dissipation back plate facing the metal substrate; Optionally, the porosity of the wire mesh is 60% to 90%.

6. The heat dissipation structure according to claim 4, characterized in that: In the sealed cavity, a plurality of spray nozzles are spaced apart on the side of the heat dissipation back plate facing the metal substrate, and each of the spray nozzles faces the metal substrate and is used to spray the gas-liquid phase change insulating medium in liquid state into the groove.

7. The heat dissipation structure according to claim 1, characterized in that: The thermal conductivity of the heat dissipation back plate is not less than 10W / (m·K); Optionally, the heat dissipation back plate is made of metal, ceramic or resin; Optionally, the heat dissipation backplate is made of copper.

8. The heat dissipation structure according to claim 1, characterized in that: A heat dissipation element is provided on a side of the heat dissipation back plate facing away from the metal substrate; Optionally, the heat sink includes heat dissipation fins; Optionally, the heat sink includes a liquid cooling plate.

9. A power device, characterized in that: The heat dissipation device comprises a chip and the heat dissipation structure according to any one of claims 1 to 8; the chip is welded to a side of the metal substrate facing away from the heat dissipation back plate.

10. The power device according to claim 9, characterized in that: The power terminal of the chip is welded to a side of the metal substrate facing away from the heat dissipation back plate.

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