An ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation

Abstract

The present invention discloses an ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation, belonging to the field of multi-heat-source heat dissipation of mobile terminal integrated electronic devices. The vapor chamber includes an upper shell plate, an ultra-thin metal wire mesh, a snowflake-like wick, and a lower shell plate. A sealed cavity is formed between the upper shell plate and the lower shell plate through a sealed connection. The upper layer in the sealed cavity is the ultra-thin metal wire mesh, and the lower layer is the snowflake-like wick. Channels are engraved on the snowflake-like wick, and a liquid working medium is provided inside the channels. The snowflake-like wick designed by the present invention adopts multiple intersecting channels to increase the evaporation area, and at the same time ensures that there are corresponding intersection centers near multiple unevenly distributed heat sources, avoiding local dry evaporation caused by uneven distribution of multiple heat sources and increasing the heat diffusion performance; a hydrophobic film layer is coated on the wire mesh to accelerate the reflux speed of the working medium. In the case of dealing with heat dissipation of two heat sources, the temperature difference at each position of the upper shell plate is small, and the temperature uniformity effect is excellent.

Description

Technical Field

[0001] The present invention relates to the design of an ultra-thin snowflake-like vapor chamber, and particularly to an ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation, belonging to the field of multi-heat-source heat dissipation of integrated electronic devices of mobile terminals. Background Art

[0002] With the development of communication technologies, especially 5G technology, the power of various mobile terminals has gradually increased. The power consumption of 5G chips is more than 2.5 times that of 4G chips, bringing higher heat dissipation challenges. At the same time, due to the miniaturization and functional diversification of mobile terminals, the integration degree of chips has also increased. Coupled with the additional heat generated by fast charging, problems such as an increasing number of heat sources, high heat generation of heat sources, and uneven heat dissipation have emerged in various current mobile terminals. These problems will directly affect the service life and safety of the machine.

[0003] Currently, among the heat dissipation solutions for integrated chips, there are three mainstream heat dissipation solutions: heat pipes, graphite sheets, and vapor chambers. In the high-power consumption field, vapor chambers can already be used on a large scale. However, due to the simple design of various traditional vapor chambers, they are not targeted at highly integrated systems. Patent CN 109579583 A discloses a leaf-like vapor chamber, and the channels on the wick diverge from the center to the surroundings. This structure only has a good heat dissipation effect on the heat source at the center. Once a heat source is generated in another place, local dry-out will occur, greatly reducing the heat dissipation rate of the entire vapor chamber. Patent CN110267494 A discloses a bionic wick with a cobweb structure and a vapor chamber using the same. The liquid working medium can quickly diffuse in the wick, but the gas condensation area is insufficient, and the problem of condensation and reflux of the working medium cannot be solved. The condensation and reflux process will surely be the main part of the thermal resistance of the entire vapor chamber. In highly integrated mobile terminals, there are many heat sources. In this case of multi-heat sources, there is often a situation where the heat dissipation of a certain heat source cannot be satisfied, leading to an increase in the temperature of the entire system. At the same time, the vapor chamber also needs to consider the problem of the reflux of the liquid working medium. The common reflux solutions for vapor chambers are very simple, and the coping effect for complex multi-heat-source situations is not very good. Summary of the Invention

[0004] The purpose of the present invention is to provide an ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation, which can solve the multi-heat-source heat dissipation problem, prevent local overheating of integrated chips, and effectively reduce the heating temperature of high-power chips.

[0005] In view of the various situations existing in the above prior art, the present invention proposes a snowflake-like wick that can be designed specifically according to the number and position distribution of heat sources, ensuring that each heat source can correspond to a sufficient evaporation area, and the micro-nano structure of the secondary channels further promotes liquid evaporation. At the same time, an ultra-thin metal mesh is designed, and steam diffuses through the metal wire mesh to the entire plane to accelerate condensation and reflux, so as to solve the problem of liquid reflux. The heat pipe provided by the present invention can be applied to the heat dissipation of devices with multiple heat sources, and each process of evaporation and condensation of the working medium is enhanced, and the heat diffusion efficiency is higher.

[0006] An ultra-thin snowflake-like heat pipe for multi-heat-source heat dissipation, the heat pipe includes an upper shell plate, an ultra-thin metal wire mesh, a snowflake-like wick and a lower shell plate. The upper shell plate and the lower shell plate are hermetically connected to form a sealed cavity. Inside the sealed cavity, the upper layer is an ultra-thin metal wire mesh, and the lower layer is a snowflake-like wick. Channels are engraved on the snowflake-like wick, and a liquid working medium is provided inside the channels.

[0007] The upper and lower surfaces of the ultra-thin metal wire mesh are respectively attached to the upper shell plate and the snowflake-like wick, the lower surface of the snowflake-like wick is attached to the lower shell plate, and snowflake-like channels are engraved on the upper surface of the snowflake-like wick. The sealed cavity is evacuated and a liquid working medium is injected into the channels.

[0008] The channels of the snowflake-like wick include main channels and secondary channels. The main channels are the main trunks for quickly flowing the liquid working medium to the corresponding heat source positions; the secondary channels are the branches of the main channels, radiating out centered on each heat source position to ensure the rapid evaporation of the liquid in the channels and the rapid reflux of the steam into the main channels; the width of the main channels is between 0.1 mm and 0.4 mm, and the depth is between 0.1 mm and 0.3 mm.

[0009] The divergence direction of the main channels follows two criteria: (1) pointing to each corner of the snowflake-like wick and extending as much as possible to increase the channel area; (2) pointing to the position of each heat source to ensure multi-heat-source heat dissipation.

[0010] The main channels generally diverge from the geometric center of the snowflake-like wick to the surrounding areas according to the positions of the heat sources, extending to each corner of the snowflake-like wick and the position of each heat source; at each corner of the snowflake-like wick and the position of each heat source where the main channels extend, secondary channels extending radially around are provided to form a plurality of snowflake-like independent unit structures. The independent unit structures have a plurality of cross channels, increasing the evaporation area and at the same time ensuring that there are corresponding cross centers near a plurality of unevenly distributed heat sources.

[0011] A carbon nanotube layer or micro-nano structures such as nano-cones for facilitating liquid evaporation are also provided in the secondary channels, and the thickness of the micro-nano structures ≤ 10 μm.

[0012] The parts of the upper surfaces of the ultra-thin metal wire mesh and the snowflake-like wick that are not engraved with channels are coated with a hydrophobic layer with hydrophobic function. A hydrophobic coating is used. The thickness of the snowflake-like wick is between 0.3 mm and 0.4 mm. According to different substrate materials, a superhydrophobic surface can be constructed by means of electrodepositing stearic acid / Al hydrophobic surface, adding an organic molecular film (such as 1-dodecanethiol), or using a metal modification method.

[0013] The snowflake-like wick can be made of oxygen-free copper, copper alloy, aluminum alloy, diamond / copper composite material, etc. The main channels and secondary channels are made by etching, and micro-nano structures are generated by electrochemical deposition technology.

[0014] The liquid working medium described can be a working medium with good affinity to the wick material or a non-toxic working medium, or some nanofluids can be selected for enhancing heat dissipation. For example, the liquid working medium is pure water, acetone, etc.

[0015] The thicknesses of the upper shell plate and the lower shell plate are both between 0.1 mm and 0.3 mm. The upper shell plate and the lower shell plate need to select the same material, and a high thermal conductivity material or a material with a coefficient of thermal expansion matching that of the heat source material can be used. The materials of the upper shell plate and the lower shell plate are oxygen-free copper, copper alloy, aluminum alloy, diamond / copper composite material.

[0016] The upper shell plate and the lower shell plate can be combined by welding. A protruding edge can be provided on the lower shell plate to wrap the upper shell plate, the ultra-thin metal wire mesh and the snowflake-like wick completely, or the lower shell plate does not have an edge.

[0017] The ultra-thin metal wire mesh is woven from extremely fine metal wires, which plays a role in supporting the upper shell plate and accelerating the condensation and reflux of liquid. The thickness of the ultra-thin metal wire mesh is between 0.01 mm and 0.05 mm. In order to ensure similar coefficients of thermal expansion, the material of the wire mesh needs to be made of fine wires of the same material as the upper shell plate, the lower shell plate, and the snowflake-like wick, that is, the materials of the upper shell plate, the lower shell plate, the snowflake-like wick, and the wire mesh in the heat pipe are the same.

[0018] The shape of the heat pipe of the present invention can be designed into any polygon or circle according to requirements.

[0019] In the present invention, the channel shape of the snowflake-like wick is designed according to the morphology of snowflake solidification to create a shape for addressing the multi-heat-source heat dissipation problem: the main channel serves as the trunk of the snowflake-like crystal, connecting all heat sources, while the secondary channels radiate outward from the center of each heat source in a radial pattern. The divergence direction of the main channel follows two criteria: 1. Pointing to each corner of the polygon to extend as much as possible and increase the channel area; 2. Pointing to the position of each heat source to ensure multi-heat-source heat dissipation. This design corresponds each heat source to a channel concentration intersection area, specifically increasing the heat dissipation area, enabling the solution of the multi-heat-source heat dissipation problem.

[0020] Due to the very small thickness of the heat pipe, the flow resistance of the liquid working medium in the channel is very large. The main channel of the snowflake-like wick is relatively wide to accelerate the flow rate of the liquid working medium, effectively reducing the flow resistance of the liquid working medium; the secondary channels evenly distribute the liquid working medium near the heat source center, increasing the total surface area and the evaporation rate. The secondary channels need to be processed inside the channel by adding some micro-nano structures such as nano-cones or carbon nanotube layers to further increase the evaporation rate of the liquid working medium in the secondary channels.

[0021] At the same time, the ultra-thin metal wire mesh diffuses the steam across the entire heat pipe plane, solving the problem that traditional bionic heat pipes cannot expand the heat dissipation area, increasing the heat dissipation rate and condensation rate of the system. The steam condenses in a bead-like manner on the hydrophobic layer of the ultra-thin metal wire mesh, further accelerating the liquid reflux. The liquid working medium returns through each channel to complete the cycle. The thickness of the ultra-thin metal wire mesh is much smaller than that of the snowflake-like wick, and the remaining liquid working medium will not affect the circulation of the entire system. Effectively solving the problem of the decline in the heat transfer performance of the ultra-thin heat pipe.

[0022] The present invention has the following advantages compared with the prior art:

[0023] The snowflake-like wick structure of the present invention solves the problem of multi-heat-source heat dissipation. This technology can adopt corresponding designs according to actual situations to ensure that each heat source corresponds to a channel concentration intersection area during use, and has better effects in the face of small spaces and complex heat dissipation conditions. The use of the ultra-thin metal wire mesh not only supports the upper and lower plate shells together with the wick, but also expands the condensation area of the gas. The wire mesh structure contains a large number of voids, greatly increasing the condensation reflux speed and preventing the occurrence of local dry burning. Significantly improving the heat transfer power of the ultra-thin heat pipe. Description of the Drawings

[0024] Figure 1 It is an exploded schematic diagram of the ultra-thin heat pipe structure provided by the present invention.

[0025] Figure 2 It is an overall schematic diagram of the snowflake-like wick structure provided by the present invention.

[0026] Figure 3 Schematic diagram of an independent unit of the snowflake-like wick structure provided by the present invention.

[0027] Figure 4 Partial cross-sectional schematic diagram of the snowflake-like wick structure provided by the present invention.

[0028] Figure 5 Schematic diagram of the irregular ultra-thin vapor chamber provided by the present invention.

[0029] Figure 6 Schematic diagram of the circular ultra-thin vapor chamber provided by the present invention.

[0030] Figure 7 Schematic diagram of another independent unit of the snowflake-like wick structure provided by the present invention.

[0031] Description of reference numerals:

[0032] 1 Upper shell plate 2 Ultra-thin metal wire mesh

[0033] 3 Snowflake-like wick 4 Lower shell plate

[0034] 5 Micro-nano structure 31 Main channel

[0035] 32 Secondary channel Detailed implementation manners

[0036] The following will elaborate on the detailed implementation manners in the embodiments of the present invention in conjunction with the accompanying drawings. However, the implementation manners of the present invention are not limited thereto.

[0037] As Figure 1 shown, the ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation of the present invention is composed of an upper shell plate 1, an ultra-thin metal wire mesh 2, a snowflake-like wick 3, and a lower shell plate 4. The upper shell plate 1 and the lower shell plate 4 are hermetically connected to form a sealed cavity. Inside the sealed cavity, there is an ultra-thin metal wire mesh 2 with an upper surface attached to the upper shell plate 1 and a lower surface attached to the snowflake-like wick 3. The lower surface of the snowflake-like wick 3 is attached to the lower shell plate 4 and channels are engraved on the upper surface. The sealed cavity is evacuated and a liquid working medium is injected into the channels.

[0038] As Figures 2-3As shown in the figure, the channels on the snowflake-like wick 3 are divided into main channels 31 and secondary channels 32. The main channels 31 are the main trunks, which are used to quickly flow the liquid working medium to the corresponding heat source positions. The secondary channels 32 are the branches of the main channels 31, and they radiate out centered on each heat source position to ensure the rapid evaporation of the liquid in the channels and the rapid reflux of the steam into the main channels 31. The width of the main channels 31 is between 0.1 mm and 0.4 mm, and the depth is between 0.1 mm and 0.3 mm. The parts of the upper surface of the snowflake-like wick 3 without channels are coated with a hydrophobic layer with hydrophobic function. The thickness of the snowflake-like wick 3 is between 0.3 mm and 0.4 mm.

[0039] As Figure 2 shown in the figure, the divergence direction of the main channels 31 follows two criteria: 1. Pointing to each corner of the snowflake-like wick 3, extending as much as possible to increase the channel area; 2. Pointing to the position of each heat source to ensure multi-heat-source heat dissipation. That is, the main channels 31 generally diverge from the geometric center of the heat sink to the surrounding, and the main channels 31 extend to each corner of the snowflake-like wick 3 and the position of each heat source; at each corner of the snowflake-like wick 3 and the position of each heat source where the main channels 31 extend, secondary channels 32 extending radially around are arranged to form a snowflake-like independent unit structure, and the independent unit structure has multiple cross channels.

[0040] The liquid working medium injected into the channels of the snowflake-like wick 3 can be pure water, acetone, etc., or other working media with good affinity can be selected according to the wick material; some non-toxic working media can be selected according to the working environment to prevent the harm caused by leakage; in order to enhance heat dissipation, some nanofluids can also be selected, and there is no limitation here.

[0041] As Figure 4 shown in the figure, micro-nano structures 5 such as carbon nanotube layers or nano-cones for facilitating liquid evaporation are also arranged in the secondary channels. The thickness of the micro-nano structures 5 is between 5 μm and 10 μm. The snowflake-like wick 3 can be made of oxygen-free copper, copper alloy, aluminum alloy, diamond / copper composite material. The main channels 31 and secondary channels 32 are made by etching method, and the micro-nano structures 5 are generated by electrochemical deposition technology. Different technical methods can be adopted according to different wick materials to prepare nano-cones or add some micro-nano structures 5 such as carbon nanotube layers. Generally, the micro-nano structures 5 are consistent with the material of the snowflake-like wick 3. For example, for copper alloy, copper nano-cones and copper nano-columns are prepared by electrochemical deposition method.

[0042] The ultra-thin metal wire mesh 2 is made of extremely fine metal wires, which plays a role in supporting the upper shell plate and accelerating the condensation and reflux of the liquid. The thickness of the ultra-thin metal wire mesh 2 can be adjusted according to the actual thickness of the required heat sink. The thickness of the ultra-thin metal wire mesh 2 is between 0.01 mm and 0.05 mm. The ultra-thin metal wire mesh 2 is coated with a hydrophobic layer with hydrophobic function.

[0043] The thicknesses of the upper plate shell 1 and the lower shell plate 4 are both between 0.1 mm and 0.3 mm. The upper shell plate 1, the snowflake-like wick 3, and the lower shell plate 4 are all made of oxygen-free copper, copper alloy, aluminum alloy, diamond / copper composite material, or other high thermal conductivity materials. If necessary, materials with a thermal expansion coefficient matching that of the heat source material can be used as required, which is not limited here. The ultra-thin metal wire mesh 2 is made of filaments of the same material as the overall structure.

[0044] The lower shell plate 4 and the upper shell plate 1 can be joined by welding. Protruding edges can be provided on the lower shell plate 4 to wrap the upper shell plate 1, the ultra-thin metal wire mesh 2, and the snowflake-like wick 3 entirely, or the lower shell plate 4 can be directly welded to the upper shell plate 1 without forming edges for wrapping. The processing method and the joining method are not limited here.

[0045] The heat pipe can be designed into any polygon or circle according to requirements.

[0046] Example 1

[0047] An ultra-thin snowflake-like heat pipe for multi-heat source heat dissipation, as Figure 1 shown, includes an upper shell plate 1, an ultra-thin metal wire mesh 2, a snowflake-like wick 3, and a lower shell plate 4. The snowflake-like wick 3 has a main channel 31 and secondary channels 32, and there are micro-nano structures 5 in the secondary channels 32. The upper shell plate 1 and the lower shell plate 4 are tightly joined and sealed under vacuum to form a cavity. The upper layer in the cavity is the ultra-thin metal wire mesh 2, and the lower layer is the snowflake-like wick 3. Adjacent layers are in contact with each other.

[0048] The upper shell plate 1, the snowflake-like wick 3, and the lower shell plate 4 are all made of copper plates. The ultra-thin metal wire mesh 2 is made of filaments of the same material as the overall structure. At the same time, the entire heat pipe needs to be ultra-thin, and the overall plate thickness should be ≤1 mm. The plate thicknesses of the upper shell plate 1 and the lower shell plate 4 are both 0.3 mm, the substrate thickness of the snowflake-like wick 3 is 0.35 mm, and the thickness of the ultra-thin metal wire mesh 2 is 0.03 mm. The heat pipe in this example is a rectangle with similar length and width. The length of the lower plate shell 4 is 60 mm, and the width is 50 mm. Protruding edges are provided on the lower shell plate 4 to wrap the upper shell plate 1, the ultra-thin metal wire mesh 2, and the snowflake-like wick 3 entirely. The thickness at the edge of the lower shell plate 4 is 0.98 mm, and the lower shell plate 4 and the upper shell plate 1 are joined by welding. The lengths of the upper shell plate 1, the ultra-thin metal wire mesh 2, and the snowflake-like wick 3 are all 58 mm, and the width is 48 mm. The liquid working medium injected into the channels of the snowflake-like wick 3 is pure water.

[0049] As Figure 2As shown, the main channels 31 on the snowflake-like wick 3 generally diverge from the geometric center of the heat pipe, and the divergence directions of the main channels 31 follow two criteria: 1. Pointing to each corner of the polygon, extending as much as possible to increase the channel area; 2. Pointing to the position of each heat source to ensure heat dissipation for multiple heat sources. In this embodiment, the heat pipe faces two symmetrical heat sources. After the main channels 31 diverge from the center, they first point to the four corners of the rectangle to ensure that the liquid working medium has sufficient evaporation area. Then they diverge towards the two heat sources, enabling the heat at the heat source to be transferred to the liquid working medium in a timely manner. As Figure 3 shown, it is a snowflake-like independent unit structure. The main channel 31 is the trunk of the independent unit structure, with a width of 0.4 mm. Due to the relatively wide width, the flow resistance of the working medium in the main channel 31 is reduced, and the liquid working medium can be transported to each independent unit, ensuring that the working medium in the unit at the heat source is not evaporated dry and that the working medium in the unit without a heat source evaporates and dissipates heat in a timely manner. The secondary channels 32 are the branches of the independent unit structure, with a width of 0.1 mm. The secondary channels 32 diverge around the heat source with the main channel 31 as the trunk, forming a snowflake-like shape to increase the heat dissipation area as much as possible. At the same time, some nanocones are generated in the secondary channels 32 through electrochemical deposition technology. The nanocones are generally electro-deposited from metal ions of the same material as the wick. As Figure 4 shown, the generated micro-nano structure 5 has a thickness of 10 μm. The addition of the micro-nano structure 5 can enhance the capillary force to fill the secondary channels 32 with the liquid working medium, ensuring the heat exchange area and further enhancing the evaporation of the liquid working medium.

[0050] The ultra-thin metal wire mesh 2 covers the snowflake-like wick 3, enabling the steam to diffuse over the entire surface, greatly increasing the condensation area. At the same time, a hydrophobic layer is coated on the ultra-thin metal wire mesh 2 to make the condensation efficiency higher. The steam condenses on the ultra-thin metal wire mesh 2 and quickly flows back into the channels of the heat pipe. The thickness of the ultra-thin metal wire mesh 2 accounts for a small proportion of the entire cavity, and the resulting liquid accumulation problem can be ignored. At the same time, it can play a supporting role and increase the reliability of the entire heat pipe.

[0051] Embodiment 2

[0052] As Figure 5 shown, the difference between this embodiment and Embodiment 1 is that: the shape of the heat pipe is an irregular polygon, the upper shell plate 1, the snowflake-like wick 3, and the lower shell plate 4 are all made of aluminum plates, and the ultra-thin metal wire mesh 2 is made of thin filaments of the same material as the overall structure. The rest is the same as in Embodiment 1.

[0053] Embodiment 3

[0054] As Figure 6As shown, the difference between this embodiment and Embodiment 1 is that: the shape of the heat sink plate is circular, and the lower housing plate 4 has no edge and is directly welded to the upper housing plate 1. The rest is the same as in Embodiment 1.

[0055] Embodiment 4

[0056] As Figure 7 shown, the difference between this embodiment and Embodiment 1 is that: the shapes of the independent units of the snowflake-like wick structure are different, all being snowflake-like.

[0057] The shapes of the independent units can have many forms and are not enumerated here. The rest is the same as in Embodiment 1.

[0058] The lower surface of the upper housing plate of the present invention is hermetically combined with the upper surface of the lower housing plate, and a vacuum cavity is formed therebetween. There is a copper mesh structure in the upper layer of the cavity to facilitate steam condensation, and a snowflake-like wick with its lower surface tightly combined with the lower housing plate in the lower layer of the cavity. The wick is designed according to the crystal structure of snowflakes, and the main channels are radially distributed on the wick body, with radial secondary channels added centered on each heat source. The snowflake-like wick designed by the present invention adopts a plurality of intersecting channels to increase the evaporation area, and at the same time ensures that there are corresponding intersection centers near multiple unevenly distributed heat sources, avoiding local dry-out caused by uneven distribution of multiple heat sources and increasing the heat diffusion performance; a hydrophobic film layer is coated on the ultra-thin metal wire mesh above the snowflake-like wick to promote dropwise condensation, absorb and reflux the condensed liquid, and accelerate the reflux speed of the working medium. When the heat sink plate of the present invention deals with the heat dissipation of two heat sources, the temperature difference at each position of the upper housing plate of the present invention is small, not exceeding 0.5 °C, and the temperature equalization effect is excellent.

[0059] The above embodiments are all examples for elaborating the design of the present invention and do not limit the implementation method of the present invention. It is impossible to list all the implementation methods here, and the present invention is not limited to the above embodiments. For those skilled in the art, on the basis of the above design, parameter modifications can be made according to different functional requirements and usage environments, and these should all be within the protection scope of the present invention.

Claims

1. An ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation, characterized in that: The heat pipe includes an upper shell plate, an ultra-thin metal wire mesh, a snowflake-like wick, and a lower shell plate. A sealed cavity is formed between the upper shell plate and the lower shell plate through a sealed connection. An ultra-thin metal wire mesh is arranged in the upper layer of the sealed cavity, and a snowflake-like wick is arranged in the lower layer. Channels are engraved on the snowflake-like wick, and a liquid working medium is arranged inside the channels. Snowflake-like channels are engraved on the upper surface of the snowflake-like wick. The channels include main channels and secondary channels. The main channels are the main trunks, and the secondary channels are the branches of the main channels, radiating out radially with each heat source position as the center. The width of the main channels is between 0.1 mm and 0.4 mm, and the depth is between 0.1 mm and 0.3 mm. The divergence direction of the main channels follows two criteria: (1) pointing to each corner of the snowflake-like wick, extending as much as possible to increase the channel area; (2) pointing to the position of each heat source to ensure heat dissipation for multiple heat sources. The main channels extend from the geometric center of the heat pipe to each corner of the snowflake-like wick and the position of each heat source. Secondary channels extending radially around are arranged at each corner of the snowflake-like wick and the position of each heat source where the main channels extend, forming multiple snowflake-like independent unit structures. The independent unit structures have multiple cross channels. A hydrophobic layer with hydrophobic function is coated on the ultra-thin metal wire mesh.

2. The ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation according to claim 1, characterized in that: The upper and lower surfaces of the ultra-thin metal wire mesh are respectively attached to the upper shell plate and the snowflake-like wick. The lower surface of the snowflake-like wick is attached to the lower shell plate. The sealed cavity is evacuated and a liquid working medium is injected into the channels.

3. The ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation according to claim 1, characterized in that: A micro-nano structure of a carbon nanotube layer or nano-cones is also arranged in the secondary channels, and the thickness of the micro-nano structure is ≤ 10 μm.

4. The ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation according to claim 1, characterized in that: The part of the upper surface of the snowflake-like wick where no channels are engraved is coated with a hydrophobic layer with hydrophobic function. The thickness of the snowflake-like wick is between 0.3 mm and 0.4 mm. The snowflake-like wick is made of oxygen-free copper, copper alloy, aluminum alloy, or diamond / copper composite material. The main channels and secondary channels are made by etching, and the micro-nano structure is generated by electrochemically depositing technology.

5. The ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation according to claim 1, characterized in that: The ultra-thin metal wire mesh is made of metal wires, and the thickness of the ultra-thin metal wire mesh is between 0.01 mm and 0.05 mm.

6. The ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation according to claim 1, characterized in that: The thicknesses of both the upper shell plate and the lower shell plate are between 0.1 mm and 0.3 mm. The upper shell plate and the lower shell plate are combined by welding. A protruding edge is arranged on the lower shell plate to wrap the upper shell plate, the ultra-thin metal wire mesh, and the snowflake-like wick completely, or the lower shell plate does not have an edge. The upper shell plate, the lower shell plate, the snowflake-like wick, and the ultra-thin metal wire mesh are made of the same material.

7. The ultra-thin snowflake-like vapor chamber for multi-heat-source heat dissipation according to claim 1, characterized in that: The shape of the heat pipe is a polygon or a circle.

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