Nanometer porous wick vapor chamber and preparation method thereof

Abstract

The invention relates to a nano-porous wick vapor chamber and a preparation method thereof in the vapor chamber heat dissipation technology, and the preparation method comprises the following steps: preparing an upper cover plate and a lower cover plate, and printing a template structure sacrificial layer on one side of the upper cover plate by using 3D printing equipment; electroplating is conducted on the printed upper cover plate to deposit porous nano-copper, and a nano-copper structure is obtained on the side, provided with the template structure sacrificial layer, of the upper cover plate and located in a set area outside the template structure sacrificial layer; calcining the electroplated upper cover plate, and removing the sacrificial layer of the template structure on the upper cover plate while curing the porous nano-copper structure; the upper cover plate and the lower cover plate are packaged, liquid is injected, degassing and sealing treatment are carried out, and the vapor chamber is prepared. According to the vapor chamber prepared through the preparation method, the liquid absorption performance of the liquid absorption core of the vapor chamber can be improved, and the structural stability of the liquid absorption core can be improved.

Description

Technical Field

[0001] The present application relates to the field of heat dissipation technology, and in particular to a nanoporous liquid wick heat spreader and a preparation method thereof. Background Art

[0002] With the rapid development of electronics, solar energy, communications, IT, LED and other industries, the heat generation power inside various devices is getting higher and higher, and the heat flux density is constantly increasing, causing the temperature inside the device to rise sharply, and the traditional heat dissipation components cannot meet the current heat dissipation needs. Most traditional heat dissipation is a heat dissipation method that combines heat sources and heat sinks. The heat is exchanged in the air by the heat sink to achieve a cooling effect. However, due to the heat transfer properties of the material, spatial structure, weight and stability of the heat dissipation module, it is difficult for traditional heat dissipation to solve the related heat transfer problems when it comes to specific small spaces, high heat flux density, and high-power devices.

[0003] The heat spreader is a heat transfer element with ultra-high thermal conductivity. It is generally composed of a shell, a support column, a vacuum cavity (steam cavity), a wick and a working fluid. It achieves efficient heat exchange through the huge latent heat of the internal working fluid gas-liquid phase change. It can evenly distribute heat to a larger area of ​​equipment and has been widely used in electronic devices, optical equipment, and heat exchange. However, the current preparation of the wick structure still has problems such as unclear optimization of the structural direction and unstable heat dissipation performance. Summary of the invention

[0004] In view of the problems existing in the background technology, the present application provides a nanoporous liquid absorbent core vapor chamber and a preparation method thereof, wherein the preparation method can improve the liquid absorption performance of the liquid absorbent core of the vapor chamber and can improve the structural stability of the liquid absorbent core.

[0005] According to one aspect of the present invention, a method for preparing a nanoporous liquid-absorbing core heat spreader is provided, comprising: preparing an upper cover plate and a lower cover plate, and printing a template structure sacrificial layer on one side of the upper cover plate by using a 3D printing device; electroplating is performed on the printed upper cover plate to deposit porous nano-copper, and a nano-copper structure is obtained in a set area on the side of the upper cover plate with the template structure sacrificial layer and outside the template structure sacrificial layer; calcining the electroplated upper cover plate, and removing the template structure sacrificial layer on the upper cover plate while curing the porous nano-copper structure; packaging the upper cover plate and the lower cover plate, injecting liquid, degassing, and sealing to prepare the heat spreader.

[0006] In some embodiments of the present invention, the height of the sacrificial layer of the template structure is 0.01-0.2 mm.

[0007] In some embodiments of the present invention, the electroplating deposition of porous nano-copper on the upper cover comprises the following steps: preparing a nano-copper electroplating solution, placing the prepared electroplating solution in an electrolytic cell, using a copper plate as an anode and the printed upper cover as a cathode, and performing electroplating to deposit porous nano-copper.

[0008] In some embodiments of the present invention, the molar ratio of CuSO4 to H2SO4 in the electroplating solution is (0.35-0.55):(1.45-1.85).

[0009] In some embodiments of the present invention, the temperature of the electroplating solution during the electroplating process is 20-40°C, and the current density is 3-5A / cm 2 , the electroplating time is 20 to 40S.

[0010] In some embodiments of the present invention, the calcination temperature of the electroplated upper cover plate is 400-500° C., and the calcination time is 60-120 min.

[0011] In some embodiments of the present invention, after the electroplated upper cover plate is calcined, the temperature is cooled to room temperature at a cooling rate of 3 to 6° C. per minute.

[0012] In some embodiments of the present invention, the vapor chamber is an ultra-thin vapor chamber with gas and liquid coplanar, the template structure sacrificial layer is designed according to the position of the porous nano-copper structure, and the template structure sacrificial layer is staggered with the porous nano-copper structure.

[0013] In some embodiments of the present invention, the heat spreader is a conventional heat spreader with different gas and liquid surfaces, and the sacrificial layer of the template structure is designed according to the positions of the support columns arranged in an array. The sacrificial layer of the template structure coincides with the support columns arranged in an array, and before the upper cover plate and the lower cover plate are packaged, the support columns are welded between the upper cover plate and the lower cover plate.

[0014] According to another aspect of the present invention, a vapor chamber prepared by the method for preparing the above-mentioned nanoporous liquid wick vapor chamber is provided.

[0015] The embodiment of the present application provides a method for preparing a nanoporous liquid-absorbing core heat spreader. The preparation method uses a method for preparing a heat spreader by electrodepositing nano-copper to generate nano-copper during the electroplating process of an upper cover plate, and an independent porous structure can be obtained through calcination and solidification, which improves the liquid absorption performance of the nano-copper structure as a liquid-absorbing core. At the same time, after high-temperature treatment, the structure of the nano-copper as a liquid-absorbing core is more stable, which is beneficial to extending the life of the heat spreader; its unique nano-copper porous structure increases the specific surface area of ​​the material, and the increase in porosity improves the liquid absorption capacity of the heat spreader; the prepared heat spreader has good stability and temperature-averaging performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0017] Figure 1 It is a flowchart of preparing a heat spreader by electroplating and depositing porous nano-copper in the present invention;

[0018] Figure 2 It is a cross-sectional view of the overall structure of the gas-liquid coplanar ultra-thin heat sink in the present invention;

[0019] Figure 3 Schematic diagram of the overall structure of the gas-liquid coplanar ultra-thin heat sink in the present invention;

[0020] Figure 4 It is a cross-sectional view of the overall structure of a conventional vapor chamber with different gas and liquid surfaces in the present invention;

[0021] Figure 5 It is a schematic diagram of the overall structure of a conventional vapor chamber with different gas and liquid surfaces in the present invention;

[0022] Figure 6 This is a picture of nanoporous copper electroplated and deposited on the upper cover plate in Example 1 of the present invention;

[0023] Figure 7 This is a picture of nanoporous copper after solidification after electroplating deposition on the upper cover plate in Example 1 of the present invention.

[0024] The reference numerals in the accompanying drawings represent the following: 1. upper cover plate; 2. sacrificial layer of template structure; 3. nano copper structure; 4. lower cover plate; 5. cavity; 6. support column. DETAILED DESCRIPTION

[0025] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0026] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are only examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims.

[0027] In the description of the present application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previously associated objects are in an "or" relationship.

[0028] A first aspect of the present invention provides a method for preparing a nanoporous liquid wick vapor chamber.

[0029] like Figure 1 As shown, the preparation method comprises the following steps:

[0030] S1. Plate and shell 3D printing processing.

[0031] In the present invention, an upper cover plate and a lower cover plate are first prepared, and then a template structure sacrificial layer is printed on one side of the upper cover plate using a 3D printing device.

[0032] In some embodiments of the present invention, the design of the sacrificial layer of the template structure is different depending on the type of the designed heat spreader. The heat spreaders prepared in the present invention include ultra-thin heat spreaders with gas and liquid coplanarity and conventional heat spreaders with gas and liquid skewed surfaces.

[0033] like Figure 2 and Figure 3 As shown, the gas-liquid coplanar ultra-thin heat spreader includes an upper cover plate 1, a nano-copper structure 3, a lower cover plate 4 and a cavity 5; when the prepared heat spreader is a gas-liquid coplanar heat spreader, the template structure sacrificial layer 2 is designed according to the position of the nano-copper structure 3, and the template structure sacrificial layer 2 is misaligned with the porous nano-copper structure.

[0034] like Figure 4 and Figure 5 As shown, the conventional gas-liquid unequal-surface vapor chamber comprises an upper cover plate 1, a nano-copper structure 3, a lower cover plate 4, a support column 6 and a cavity 5; when the prepared vapor chamber is a gas-liquid unequal-surface vapor chamber, the template structure sacrificial layer 2 is designed according to the position of the support columns 6 arranged in an array, and the template structure sacrificial layer 2 coincides with the position of the support columns 6 arranged in an array.

[0035] In some embodiments of the present invention, the height of the sacrificial layer of the template structure can be 0.01-0.2 mm; it should be noted that the height of the sacrificial layer of the template structure is not particularly limited, and those skilled in the art can make a reasonable choice based on actual needs. As some specific examples, the height of the sacrificial layer of the template structure can be 0.01 mm, 0.04 mm, 0.08 mm, 0.12 mm, 0.16 mm, 0.20 mm, etc.

[0036] In some embodiments of the present invention, a resin-based template structure sacrificial layer may be printed on the surface of the upper cover plate using a 3D printing device.

[0037] In some embodiments of the present invention, before 3D printing the sacrificial layer of the template structure, ethanol may be used to clean the upper cover plate and its surface may be polished to better bond the sacrificial layer of the template structure to the upper cover plate.

[0038] Furthermore, after the sacrificial layer of the template structure is 3D printed, the upper cover plate can be taken out and the residual resin on the surface of the upper cover plate can be cleaned with fluorinated liquid.

[0039] S2. Prepare nano copper electroplating solution.

[0040] In the present invention, the nano copper electroplating solution is obtained by dissolving copper sulfate in water and then adding the solution into concentrated sulfuric acid and mixing the mixture evenly.

[0041] In some embodiments of the present invention, copper sulfate can be selected from one of anhydrous copper sulfate and copper sulfate pentahydrate or a combination of the two; concentrated sulfuric acid can be 98% by mass; and the water used to dissolve copper sulfate is preferably ultrapure water.

[0042] In some embodiments of the present invention, the molar ratio of CuSO4 to H2SO4 in the electroplating solution is preferably (0.35-0.55):(1.45-1.85).

[0043] In some embodiments of the present invention, 60 to 80 g of copper sulfate can be dissolved in 200 to 300 ml of water, and then the copper sulfate solution is slowly added to 80 to 100 ml of concentrated sulfuric acid along the wall of the cup using a glass rod and slowly stirred, and the nano-copper electroplating solution is obtained after standing for 2 hours.

[0044] S3. Electroplating pretreatment.

[0045] In the present invention, a certain width area around one side of the upper cover plate printed with the template structure sacrificial layer in step S1 is sealed with tape, and the narrower space reserved around the upper cover plate is used for the subsequent packaging process, and the back side of the upper cover plate is completely sealed with tape to avoid electroplating deposition in these areas during the subsequent electroplating treatment. That is, the area to be electroplated is the side of the upper cover plate with the template structure sacrificial layer, and is a set area outside the template structure sacrificial layer and the tape coverage, so as to control the current density per square centimeter in the deposition area of ​​the subsequent electroplating process.

[0046] In some embodiments of the present invention, the tape may be an epoxy tape to achieve a stable seal on the non-electroplating deposition area.

[0047] It should also be noted that the operations of step S2 and step S3 are not in order, and the embodiments of the present application are only examples. It should be understood that in other implementations, it is also possible to choose to first perform electroplating pretreatment on the upper cover plate and then prepare the nano copper electroplating solution.

[0048] S4, electroplating to generate nano copper.

[0049] In the present invention, electroplating is performed on the printed upper cover to deposit porous nano-copper, and a nano-copper structure is obtained in a set area on the side of the upper cover with the template structure sacrificial layer and outside the template structure sacrificial layer.

[0050] Electroplating and depositing porous nano-copper on the upper cover specifically includes the following steps:

[0051] The prepared electroplating solution is placed in an electrolytic cell, with the copper plate as the anode and the printed upper cover as the cathode, and electroplating is performed to deposit porous nano-copper.

[0052] In some embodiments of the present invention, the temperature of the plating solution during the electroplating process is 20-40°C, and the current density is 3-5 A / cm 2 , the electroplating time is 20 to 40S.

[0053] In some embodiments of the present invention, before electroplating the printed upper cover, the oil stains on the surface of the upper cover can be removed by sodium hydroxide solution, and then the residual sodium hydroxide on the surface of the upper cover is rinsed with pure water, and then the upper cover is connected to the negative pole of the power supply and the positive pole is connected to the polished copper plate, so as to improve the quality of electroplating.

[0054] S5, calcining and solidifying the nano copper.

[0055] In the present invention, the electroplated upper cover plate is calcined, and the template structure sacrificial layer on the upper cover plate is removed while the porous nano-copper structure is solidified.

[0056] In some embodiments of the present invention, the calcination temperature of the electroplated upper cover plate is 400-500° C., and the calcination time is 60-120 min.

[0057] Furthermore, the upper cover plate is preferably heated to the calcination temperature at a heating rate of 10° C. per minute, thereby completing the solidification of the nano copper and the removal of the resin water flow channel (template structure sacrificial layer).

[0058] In some embodiments of the present invention, after the electroplated upper cover plate is calcined, the temperature is cooled to room temperature at a cooling rate of 3 to 6° C. per minute. The cooling process takes about 60 to 120 minutes.

[0059] In some embodiments of the present invention, before calcining the electroplated upper cover plate, the upper cover plate may be cleaned with ultrapure water and dried to improve the calcination quality.

[0060] In some embodiments of the present invention, a muffle furnace or other calcination equipment may be used to calcine the electroplated upper cover plate.

[0061] S6. Packaging.

[0062] In the present invention, the upper cover plate and the lower cover plate are packaged, liquid is injected, degassing is performed, vacuuming is performed, and sealing treatment is performed to finally prepare a heat spreader, and the heat spreader is prepared by using the nanoporous copper structure solidified by the upper cover plate as a liquid wick.

[0063] In some embodiments of the present invention, before packaging the upper cover plate and the lower cover plate, the upper cover plate may be polished, such as by using sandpaper, to ensure that the sealing weld is smooth, and the periphery of the upper cover plate may be carefully polished to ensure that there are no sealing holes in the packaging.

[0064] In some embodiments of the present invention, the lower cover plate and the upper cover plate can be welded and sealed by a welding edge sealing device, such as a laser welding machine, and then the upper and lower cover plates with completed edge sealing are filled with working fluid by a liquid injection and degassing device, such as injecting liquid as the working medium of the heat spreader through a liquid injector, and the interior is evacuated and sealed by a primary degassing machine, such as degassing and vacuuming by a vacuum degassing machine, and the excess external part is cut and sealed again by a secondary degassing machine, thereby obtaining a nanoporous liquid absorbent core ultra-thin heat spreader.

[0065] In some embodiments of the present invention, the working medium includes one or more of ultrapure water, ethanol, acetone and saline solution.

[0066] In addition, in some embodiments of the present invention, if the prepared vapor chamber is a conventional vapor chamber with different gas and liquid surfaces, it is necessary to weld the support column to the lower cover plate before welding and sealing the lower cover plate and the upper cover plate, and ensure that the support column is consistent with the position of the sacrificial layer of the template structure, such as Figure 5 As shown, the lower cover plate and the upper cover plate are welded and sealed.

[0067] The preparation method of the present application utilizes the method of preparing a heat spreader by electrodepositing nano-copper to generate nano-copper during the electroplating process of the upper cover plate, and an independent porous structure can be obtained through calcination and solidification, which improves the liquid absorption performance of the nano-copper structure as a liquid absorption core. At the same time, after high-temperature treatment, the structure of the nano-copper as a liquid absorption core is more stable, which is beneficial to extending the life of the heat spreader; its unique nano-copper porous structure increases the specific surface area of ​​the material, and the increase in porosity improves the liquid absorption capacity of the heat spreader; the prepared heat spreader has good stability and temperature-averaging performance.

[0068] The preparation process of the invention is simple, the raw materials are easily available, the cost is low, and the operation is simple, which is conducive to further realizing the industrial large-scale production of heat spreaders; compared with the traditional etched liquid absorption core structure, the structure of nano copper has a multi-level pore distribution to improve the liquid absorption performance, and the stable structure allows it to be applied to ultra-thin (gas-liquid coplanar) heat spreaders and conventional (gas-liquid skewed) heat spreaders according to the design scenario, which has important practical significance and technical development for improving the design method of the heat spreader.

[0069] The second aspect of the present invention provides a nanoporous liquid wick vapor chamber, and the nanoporous liquid wick vapor chamber is prepared by the preparation method provided by the first aspect of the present invention.

[0070] The preparation method of the nanoporous liquid wick vapor chamber of the present invention will be further described below in conjunction with specific embodiments.

[0071] Example 1

[0072] like Figure 2 and 3 As shown, the overall structure of the porous nano-ultra-thin heat spreader with gas and liquid coplanar is prepared, which is composed of a lower cover plate, an upper cover plate and a nano-copper structure as a liquid wick, and a resin-based template structure sacrificial layer is used to control the generation range of the porous nano-copper. The method for preparing the porous nano-ultra-thin heat spreader includes the following steps:

[0073] S1. Clean the stamped upper cover with alcohol and then polish it with sandpaper. Then print the designed resin-based template structure sacrificial layer with a height of 0.01-0.2mm under the 3D resin printer. After printing, use fluorinated liquid to clean the residual resin on the surface of the upper cover.

[0074] S2. Dissolve 100 g of copper sulfate pentahydrate crystals in 255 ml of ultrapure water, heat and stir to 50-70°C to ensure that the crystals are dissolved in the water, take 81 ml of concentrated sulfuric acid and then use a glass rod to slowly drain the prepared copper sulfate solution into the beaker close to the wall of the beaker, let it stand and cool for 2 hours to obtain a nano copper electrolytic solution.

[0075] S3. The upper cover plate in S1 with the template structure sacrificial layer printed on one side is sealed with epoxy resin tape on all sides, and the back side is completely sealed with tape to ensure that only the front side of the upper cover plate can contact the nano copper electrolytic solution during the immersion process, so as to control the current density per square centimeter.

[0076] S4. Clean the surface of a copper plate with a purity of 99.99% with sodium hydroxide, then polish the surface with sandpaper, and finally clean it with ultrapure water to remove oil stains and oxides on the surface. Connect the copper plate to the positive pole of the power supply, and the negative pole of the power supply to the upper cover plate processed in S3. Immerse both in the nano-copper electrolytic solution prepared in S2. The solution temperature is controlled between 20 and 40°C to ensure that the sacrificial layer of the template structure of the upper cover plate is completely immersed. Turn on the power supply to control the surface current density of the upper cover plate to 3 to 5A / cm 2 , the nano copper structure can be deposited on the surface of the upper cover plate. As the deposition time increases, the height of the nano copper deposition will also increase. It can be deposited to a thickness of 50 to 100 μm in 20 to 40 seconds. Its morphology is as follows Figure 6 As shown, the electrodeposition time exceeding 40S will cause the structure of the nano-copper to be blocked and lose the characteristics of the porous structure, affecting the performance of the liquid wick.

[0077] S5. Immerse the top cover plate after electrodeposition in ultrapure water for 5 to 10 minutes to ensure that the residual electrolyte on the surface is removed. Then take it out to dry and remove the protective epoxy resin tape on the surface. Place it in a muffle furnace and pass nitrogen as a protective gas for calcination. Set the temperature to 400 to 500°C within 30 to 50 minutes and calcine at this temperature for 60 to 120 minutes. Then lower the temperature to room temperature within 60 to 120 minutes to complete the solidification of nano copper. Figure 7 As shown in the figure, the surface of the nano copper after solidification is strong while retaining the original porous structure, which is beneficial to improving the liquid absorption performance as a liquid absorption core. The sacrificial layer of the template structure is completely removed after calcination, leaving only the nano copper as the liquid absorption core structure and the support for the ultra-thin heat sink. Prolonging the temperature during the calcination process will make the surface of the nano copper structure solidify more completely, but too long a time will cause the nano copper structure to twist and detach from the upper cover.

[0078] S6. After calcination, the periphery of the upper cover plate will be polished to ensure smoothness, and it will be sealed with the lower cover plate by welding. Then, a specific injector will be used to inject precise liquid into it as the working medium. The volume of the liquid accounts for 10-70% of the entire packaged ultra-thin heat spreader cavity. The commonly used working medium is composed of one or more of ultra-pure water, ethanol, acetone and salt solution. The ultra-thin heat spreader after liquid injection is placed in a low-temperature environment to ensure that it drops to a certain temperature before proceeding to the next step of vacuum degassing in a primary degassing machine. After completion, it is placed in a secondary degassing machine to cut and weld the excess ultra-thin heat spreader sealing part. After sealing, a porous nano-ultra-thin heat spreader with gas and liquid coplanar can be obtained. The internal structure is as follows: Figure 2 shown.

[0079] Example 2

[0080] like Figure 4 and Figure 5 As shown, the overall structure of the gas-liquid hot plate with different surfaces is prepared, which is composed of an upper cover plate, a lower cover plate, a support column and a porous nano-copper structure as a liquid wick. The generation range of the porous nano-copper is controlled by using a template structure sacrificial layer. The steps of preparing the gas-liquid hot plate with different surfaces are as follows:

[0081] S1. Printing pretreatment is the same as S1 in Example 1. Then, a sacrificial layer of a resin-based template structure is 3D printed with a height of 0.01-0.2 mm, which is used to reserve a position for the support column part in the gas-liquid non-uniform heat sink. After printing is completed, the residual resin on the surface of the upper cover plate is cleaned with fluorinated liquid.

[0082] S2. Prepare nano copper electrolyte.

[0083] Same as Example 1.

[0084] S3. Electroplating pretreatment.

[0085] Same as Example 1.

[0086] S4, electroplating to generate nano copper.

[0087] Same as Example 1.

[0088] S5, calcining and solidifying the nano copper.

[0089] Same as Example 1.

[0090] S6. Grind the four sides of the calcined upper cover plate cleanly, weld the support columns required for the upper gas-liquid heat spreader on the corresponding reserved support columns on the lower cover plate, and then seal and weld the lower cover plate with the upper cover plate. The subsequent liquid injection, degassing and sealing welding are the same as in Example 1. After completing the sealing and cutting of the excess parts, a porous nano-conventional heat spreader with gas-liquid surfaces can be obtained, and the internal structure is as follows Figure 4 shown.

[0091] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for preparing a nanoporous liquid wick soaking plate, characterized in that: include: Prepare an upper cover plate and a lower cover plate, and use a 3D printing device to print a template structure sacrificial layer on one side of the upper cover plate; Electroplating is performed on the printed upper cover plate to deposit porous nano-copper, and a nano-copper structure is obtained in a set area on the side of the upper cover plate with the template structure sacrificial layer and outside the template structure sacrificial layer; calcining the electroplated upper cover plate, and removing the template structure sacrificial layer on the upper cover plate while solidifying the porous nano-copper structure; The upper cover plate and the lower cover plate are packaged, liquid is injected, deaeration is performed, and sealing treatment is performed to prepare a heat spreader.

2. The preparation method according to claim 1, characterized in that: The height of the sacrificial layer of the template structure is 0.01-0.2 mm.

3. The preparation method according to claim 1, characterized in that: The electroplating deposition of porous nano-copper on the upper cover plate comprises the following steps: Prepare nano-copper electroplating solution, put the prepared electroplating solution in an electrolytic cell, use the copper plate as the anode and the printed upper cover as the cathode, and perform electroplating to deposit porous nano-copper.

4. The preparation method according to claim 3, characterized in that: The molar ratio of CuSO4 to H2SO4 in the electroplating solution is (0.35-0.55):(1.45-1.85).

5. The preparation method according to claim 3, characterized in that: During the electroplating process, the temperature of the electroplating solution is 20-40°C, and the current density is 3-5A / cm 2 , the electroplating time is 20 to 40S.

6. The preparation method according to claim 1, characterized in that: The calcination temperature of the electroplated upper cover plate is 400-500° C., and the calcination time is 60-120 minutes.

7. The preparation method according to claim 6, characterized in that: After the electroplated upper cover plate is calcined, the temperature is cooled to room temperature at a cooling rate of 3-6° C. per minute.

8. The preparation method according to claim 1, characterized in that: The heat spreader is an ultra-thin heat spreader with gas and liquid coplanar. The template structure sacrificial layer is designed according to the position of the porous nano-copper structure, and the template structure sacrificial layer is misaligned with the porous nano-copper structure.

9. The preparation method according to claim 1, characterized in that: The heat spreader is a conventional heat spreader with different gas and liquid surfaces. The sacrificial layer of the template structure is designed according to the positions of the support columns arranged in an array. The sacrificial layer of the template structure coincides with the support columns arranged in an array. Before the upper cover plate and the lower cover plate are packaged, the support columns are welded between the upper cover plate and the lower cover plate.

10. A vapor chamber obtained by the method for preparing a nanoporous liquid wick vapor chamber according to any one of claims 1 to 9.

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