Vapor chamber with porous wick with secondary structure and preparation method of vapor chamber

Abstract

The invention relates to the technical field of liquid absorption cores of vapor chambers, in particular to a vapor chamber with a porous liquid absorption core of a secondary structure and a preparation method of the vapor chamber. The preparation method comprises the following steps that an upper cover plate and a lower cover plate are prepared; cutting the metal wire mesh to obtain a wire mesh structure, and fixing the wire mesh structure on the surface of one side of the lower cover plate; electroplating is carried out on the silk screen structure of the lower cover plate to deposit nano-copper; calcining and curing the secondary structure of the silk screen electroplated with the nano-copper; and packaging the upper cover plate and the calcined lower cover plate, and performing liquid injection, degassing, sealing welding and packaging treatment to obtain the vapor chamber. According to the vapor chamber, the liquid absorption core with a secondary structure is prepared on the silk screen of the lower cover plate through electro-deposition of nano copper, the nano copper structure on the silk screen serves as the liquid absorption core through calcination and solidification, the service life of the vapor chamber can be effectively prolonged, the secondary porous structure provides multi-stage hole distribution for the liquid absorption core, multiple liquid flowing channels are provided, and heat conduction is accelerated.

Description

Technical Field

[0001] The present application relates to the technical field of liquid wicks of vapor chambers, and in particular to a vapor chamber having a secondary structure and a porous liquid wick and a preparation method thereof. Background Art

[0002] With the continuous development and popularization of electronic devices, the problem of heat dissipation has become increasingly prominent. In order to meet users' demand for high performance, manufacturers have increased the computing speed and function of core components such as processors, and the heat generated has increased dramatically. Traditional heat sinks and fans are not up to the task. The efficiency of heat sinks is limited, and fans have problems with high power consumption, space occupation, noise, and reliability, especially in thin and light devices. Against this background, heat spreader technology was born. It uses phase change materials to achieve efficient heat transfer and uniform distribution through liquid-to-gas phase change. It has the advantages of high heat dissipation efficiency, small space occupation, and no noise, and has become a key heat dissipation technology to promote the development of electronic equipment.

[0003] At present, the preparation of vapor chamber mainly forms liquid phase heat conduction by etching metal, and uses the process of internal working fluid gas-liquid phase conversion to achieve efficient heat conversion. It can be widely used in electronic products, optical devices and military equipment. However, it still has problems such as unstable internal structural materials of vapor chamber, easy damage of liquid absorption core due to long-term flow and unsatisfactory high heat conduction performance. Summary of the invention

[0004] The main purpose of the present invention is to provide a heat spreader with a porous liquid-absorbing core having a secondary structure and a preparation method thereof, aiming to solve at least one of the above-mentioned technical problems.

[0005] To achieve the above-mentioned purpose, the present invention proposes a method for preparing a heat spreader with a porous liquid-absorbing core with a secondary structure, comprising the following steps: preparing an upper cover plate and a lower cover plate; cutting a metal wire mesh to obtain a wire mesh structure, and fixing the wire mesh structure on a side surface of the lower cover plate; electroplating the wire mesh structure of the lower cover plate to deposit nano-copper; calcining and curing the wire mesh secondary structure after the nano-copper electroplating; packaging the upper cover plate and the calcined lower cover plate, and then performing liquid injection, degassing, sealing welding and packaging treatment to obtain the heat spreader.

[0006] In some embodiments of the present invention, the temperature of the electrolytic solution during the electroplating process is 15-30°C, and the current density is 5-8A / cm 2 , the electroplating time is 10 to 50S.

[0007] In some embodiments of the present invention, the electrolytic solution contains CuSO 4 With H 2 SO 4 The molar ratio is (0.3-0.5):(1-2).

[0008] In some embodiments of the present invention, the deposition thickness of the nano copper on the wire mesh structure is 30-80 μm.

[0009] In some embodiments of the present invention, the nano copper is calcined at a temperature of 400 to 500° C. and a calcination time of 60 to 90 min.

[0010] In some embodiments of the present invention, the nano copper is cooled to 20-25° C. after calcination for 60-120 min.

[0011] In some embodiments of the present invention, the mesh number of the wire mesh structure is 100 to 300 meshes.

[0012] In some embodiments of the present invention, before electroplating the screen structure on the lower cover, the front area of ​​the lower cover located around the screen structure, the back side and surrounding side walls of the lower cover are sealed.

[0013] In some embodiments of the present invention, after electroplating nano-copper on the wire mesh structure, the electroplated wire mesh structure and the lower cover are firstly cleaned and dried, and then the secondary structure of the wire mesh after the nano-copper electroplating is calcined and solidified.

[0014] To achieve the above object, the present invention further provides a vapor chamber prepared by the method for preparing the vapor chamber with a porous liquid-absorbing core having a secondary structure.

[0015] The present invention uses electrodeposited nano-copper to prepare a liquid wick with a secondary structure on the wire mesh of the lower cover plate. The nano-copper structure on the wire mesh is used as a liquid wick through calcination and solidification, which can effectively extend the life of the heat spreader. The secondary porous structure provides a multi-level pore distribution for the liquid wick, provides multiple liquid flow channels, and accelerates heat conduction.

[0016] The invention has low preparation cost, simple operation, and readily available raw materials, and can be used to better achieve the goal of industrialization and be put into use; compared with the traditional etched liquid wick structure, the design of the secondary porous structure effectively improves heat conduction and accelerates the uniform temperature and heat dissipation capacity of the heat spreader, and the more stable and reliable structure can be applied to different scenarios, which provides an effective idea for the design method of the heat spreader. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] 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:

[0018] Figure 1 Schematic diagram of the overall structure of the ultra-thin vapor chamber in the present invention;

[0019] Figure 2 is a cross-sectional view of the overall structure of the ultra-thin vapor chamber in the present invention;

[0020] Figure 3 Schematic diagram of the overall structure of a conventional vapor chamber in the present invention;

[0021] Figure 4 is a cross-sectional view of the overall structure of a conventional vapor chamber in the present invention;

[0022] Figure 5 It is a flowchart of preparing a vapor chamber according to the present invention;

[0023] Figure 6 It is a picture of the screen structure in the present invention;

[0024] Figure 7 This is a picture of the porous nano-copper structure on the screen after 5S of electrodeposition in the present invention;

[0025] Figure 8 This is a picture of the porous nano-copper structure on the screen after 15S of electrodeposition in the present invention;

[0026] Fig. 9 This is a picture of the porous nano-copper structure on the screen after 30S of electrodeposition in the present invention;

[0027] Fig.10 This is a picture of the porous nano-copper structure on the screen after 40S of electrodeposition in the present invention;

[0028] Fig.11 This is a picture of the porous nano-copper structure on the screen after 50S of electrodeposition in the present invention;

[0029] Fig.12 This is a picture of the secondary porous structure on the wire mesh of the present invention after calcination and solidification;

[0030] Fig.13 It is a capillary suction curve diagram of the wire mesh secondary porous liquid wick structure in the present invention;

[0031] Fig.14 It is a capillary suction rate diagram of the wire mesh secondary porous liquid absorbent core structure in the present invention.

[0032] The reference numerals in the accompanying drawings indicate the following: 1. upper cover plate; 2. secondary structure porous liquid absorbent core; 3. lower cover plate; 4. cavity; 5. support column. DETAILED DESCRIPTION

[0033] 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.

[0034] 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.

[0035] 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 objects associated before and after are in an "or" relationship.

[0036] The following is a description of a heat spreader with a porous liquid-absorbing core having a secondary structure and a preparation method thereof provided in an embodiment of the present application in conjunction with the accompanying drawings.

[0037] The embodiment of the present application discloses a method for preparing a heat spreader having a porous liquid-absorbing core with a secondary structure.

[0038] like Figure 1 As shown, the heat spreader includes an upper cover plate 1, a lower cover plate 3 and a secondary structure porous liquid absorbent core 2 arranged between the upper cover plate 1 and the lower cover plate 3, wherein the secondary structure porous liquid absorbent core 2 includes a wire mesh structure and porous nano-copper arranged on the surface of the wire mesh structure.

[0039] The preparation method of the vapor chamber comprises the following steps:

[0040] 1) Prepare the upper and lower covers.

[0041] 2) Cut the metal wire mesh to obtain a wire mesh structure, and fix the wire mesh structure on the inner surface of the lower cover plate.

[0042] 3) Electroplating is performed on the wire mesh structure of the lower cover plate to deposit nano copper.

[0043] 4) Calcination and solidification of the secondary structure of the wire mesh after electroplating nano-copper.

[0044] 5) The upper cover plate and the calcined lower cover plate are packaged, and then subjected to liquid injection, degassing, sealing welding and packaging processes to obtain a heat spreader.

[0045] By using the preparation method in the technical solution, nano-copper is prepared on the surface of the wire mesh structure of the lower cover plate by utilizing the electroplating deposition technology, and then the wire mesh structure together with the nano-copper is calcined and solidified by a calcination process to obtain porous nano-copper on the wire mesh structure, and a secondary structure porous liquid-absorbing core based on the wire mesh structure and the porous nano-copper can be obtained. The porous nano-copper as the liquid-absorbing core not only makes the internal structural material of the heat spreader more stable and can effectively extend the life of the heat spreader, but also the porous nano-copper as the secondary porous structure provides a multi-level pore distribution for the liquid-absorbing core, provides more liquid flow channels, increases the specific surface area of ​​the liquid-absorbing core, and has a stable structure. As a hydrophilic structure, it utilizes the internal multi-level pore distribution to accelerate liquid circulation and heat conduction, greatly improving the uniform temperature heat dissipation effect of the heat spreader.

[0046] In addition, the preparation method of the heat spreader of the present invention is simple to operate, the raw materials are easily available, and the preparation cost is low, which can better achieve the goal of industrialization and put it into use; compared with the traditional etched liquid wick structure, the design of the secondary structure porous liquid wick effectively improves heat conduction and accelerates the uniform temperature and heat dissipation capacity of the heat spreader, and the more stable and reliable structure can be applied to different scenarios.

[0047] In some embodiments of the present invention, the temperature of the electrolytic solution during the electroplating process is 15-30°C, and the current density is 5-8A / cm 2 , the electroplating time is 10 to 50S.

[0048] In this embodiment, by controlling the process parameters such as the temperature of the electrolytic solution for electroplating and depositing nano-copper, the current density and the electroplating time, a nano-copper layer with uniform and moderate thickness can be obtained on the surface of the wire mesh structure, so that after the nano-copper is calcined and solidified, the performance of the obtained porous nano-copper as a liquid absorbent core can be guaranteed, which can avoid excessive deposition of nano-copper on the surface of the wire mesh structure, resulting in blockage of the wire mesh structure and loss of the multi-level pore distribution characteristics of the porous nano-copper structure grown on its surface, thereby affecting the performance of the liquid absorbent core, and avoid insufficient deposition of nano-copper on the surface of the wire mesh structure, resulting in too low performance of the secondary structure porous liquid absorbent core.

[0049] Furthermore, the nano copper is preferably deposited on the wire mesh structure with a thickness of 30 to 80 μm, for example, a deposition thickness of 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, etc.

[0050] In some embodiments of the present invention, the CuSO 4 With H 2 SO 4 The molar ratio is (0.3-0.5):(1-2).

[0051] In this embodiment, the electrolytic solution can be obtained by dissolving copper sulfate in water and then adding the solution into concentrated sulfuric acid and mixing the mixture evenly.

[0052] 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; the water used to dissolve copper sulfate is preferably deionized water or ultrapure water; concentrated sulfuric acid can be, for example, 98% by mass concentrated sulfuric acid.

[0053] In some embodiments of the present invention, a corresponding proportion of copper sulfate crystals can be dissolved in water, concentrated sulfuric acid is slowly added along the cup wall using a glass rod according to the proportion, and the nano-copper electrolytic solution is obtained after cooling.

[0054] For example, 70-90 g of anhydrous copper sulfate is dissolved in 250-350 mL of water, and slowly added into 90-110 mL of concentrated sulfuric acid along the wall of the beaker using a glass rod and slowly stirred, and the electroplating nano-copper solution can be obtained after standing for 2 hours; or, for example, 120 g of copper sulfate pentahydrate crystals are dissolved in 295 mL of deionized water, 90 mL of concentrated sulfuric acid is taken, and the prepared copper sulfate solution is slowly drained into the beaker using a glass rod close to the wall of the beaker and then stood to cool for 2 hours to obtain a nano-copper electrolytic solution.

[0055] Furthermore, in order to ensure that the copper sulfate crystals are completely dissolved in water, the water may be heated and stirred to 50-70° C. during the dissolution process.

[0056] In some embodiments of the present invention, the nano copper is calcined at a temperature of 400 to 500° C. and a calcination time of 60 to 90 min.

[0057] In this embodiment, by controlling the process parameters such as the calcination temperature and calcination time of nano-copper, it can be ensured that the electroplated deposited nano-copper is completely solidified, so that the structure and material of the secondary structure porous liquid absorbent core composed of the wire mesh structure and porous nano-copper are more stable, and the liquid absorption capacity and liquid absorption rate of the liquid absorbent core are effectively guaranteed.

[0058] Furthermore, the temperature can be uniformly raised to 400-500° C. within 20-40 minutes and maintained at this temperature for 60-90 minutes, and the temperature can be lowered to 20-25° C. after calcining the nano-copper for 60-120 minutes.

[0059] By slowly heating and cooling the nano-copper before and after the calcination process, the microstructure can be improved and the internal stress can be reduced, thereby improving the solidification quality and further enhancing the stability of the porous nano-copper on the wire mesh structure.

[0060] In some embodiments of the present invention, the mesh number of the wire mesh structure is 100 to 300 meshes.

[0061] In this embodiment, the wire mesh structure is obtained by cutting the metal wire mesh according to the size of the heat spreader. Specifically, the wire mesh structure is cut to a distance of 1 to 2 cm from the edge of the heat spreader.

[0062] Furthermore, the wire mesh structure can be fixed to the lower cover plate by welding methods such as spot welding.

[0063] In some embodiments of the present invention, the metal wire mesh can be formed by stacking or weaving multiple layers of metal wire mesh to form a complex pore structure of varying sizes, and the pores are interconnected, so that the mesh number of the metal wire mesh (wire mesh structure) is 100 to 300 meshes, and the porous nano-copper attached to the surface of the metal wire of the wire mesh structure has a good liquid absorption effect.

[0064] In some embodiments of the present invention, the metal mesh material may be made of metal materials such as stainless steel, pure copper, aluminum alloy, copper alloy, etc.

[0065] In some embodiments of the present invention, before electroplating the screen structure on the lower cover, the front area of ​​the lower cover located around the screen structure, the back side and surrounding side walls of the lower cover are sealed.

[0066] In this embodiment, by sealing the area around the wire mesh structure on the front side of the lower cover plate, as well as the back side and surrounding side walls of the lower cover plate, the wire mesh structure can be better immersed in the electrolytic solution, thereby ensuring the electroplating effect on the wire mesh structure and the performance of the nano-copper as a liquid wick after calcination, while avoiding the deposition of nano-copper on the back side of the lower cover plate and other areas, which would affect the quality of the heat spreader.

[0067] In some embodiments of the present invention, for the area on the front side of the lower cover plate surrounding the screen structure, anti-plating glue can be evenly applied and then placed in an oven and baked at 60 to 80° C. for 30 to 60 minutes to ensure complete curing and sealing. For the back side of the lower cover plate, epoxy resin tape can be used for sealing.

[0068] In some embodiments of the present invention, after electroplating nano copper on the wire mesh structure, the electroplated wire mesh structure and the lower cover are first cleaned and dried, and then the wire mesh secondary structure after the nano copper electroplating is calcined and solidified.

[0069] Specifically, in this embodiment, the oil stains on the surface of the lower cover plate and the screen can be removed by sodium hydroxide solution, and then the residual sodium hydroxide on the surface can be rinsed clean with pure water to reduce the influence of dirt on the calcination of nano copper.

[0070] In some embodiments of the present invention, the thickness of the upper cover plate and the lower cover plate is respectively between 0.05 and 1 mm, and the material thereof can be metal materials such as stainless steel, pure copper, aluminum alloy, copper alloy, etc.

[0071] The embodiment of the present application further discloses a vapor chamber having a porous liquid-absorbing core with a secondary structure, and the vapor chamber is prepared by the preparation method provided by the present invention.

[0072] In some embodiments of the present invention, the vapor chamber may be an ultra-thin vapor chamber or a conventional vapor chamber.

[0073] like Figure 1 and Figure 2 As shown, the ultra-thin heat spreader includes an upper cover plate 1, a lower cover plate 3, a secondary structure porous liquid absorbent core 2 arranged between the upper cover plate 1 and the lower cover plate 3, and a cavity 4 formed, wherein the secondary structure porous liquid absorbent core 2 includes a wire mesh structure and porous nano-copper arranged on the surface of the wire mesh structure.

[0074] like Figure 3 and Figure 4 As shown, a conventional heat spreader includes an upper cover plate 1, a lower cover plate 3, a secondary structure porous liquid absorbent core 2 and a support column 5 arranged between the upper cover plate 1 and the lower cover plate 3, and a cavity 4 formed, wherein the secondary structure porous liquid absorbent core 2 includes a wire mesh structure and porous nano-copper arranged on the surface of the wire mesh structure.

[0075] The preparation method of the vapor chamber with a porous liquid-absorbing core having a secondary structure in the present invention will be further described below in conjunction with specific embodiments.

[0076] Embodiment 1:

[0077] like Figure 1 The figure shows the overall structure of an ultra-thin heat spreader with a secondary structure porous liquid absorbent core, which consists of an upper cover plate, a lower cover plate and a secondary structure porous liquid absorbent core, and porous nano-copper is formed on the surface of the wire mesh structure by electrodeposition as the liquid absorbent core.

[0078] like Figure 5 As shown, the preparation method thereof comprises the following steps:

[0079] S1. Punch out the upper cover and the lower cover. The upper cover has its own inwardly concave support column. Clean the stamped lower cover with alcohol.

[0080] S2. Cut the 100-300 mesh pure copper wire mesh to a size of 1-2 cm from the edge of the lower cover. The wire mesh structure is as follows: Figure 6 As shown, the wire mesh structure is fixed on the lower cover plate by spot welding.

[0081] S3. Dissolve 120 g of copper sulfate pentahydrate crystals in 295 ml of deionized water, heat and stir to 50-70°C to ensure that the crystals are dissolved in the water, take 90 ml of concentrated sulfuric acid and then use a glass rod to slowly drain the prepared copper sulfate solution into the beaker by pressing against the wall of the beaker, let it stand and cool for 2 hours to obtain a nano copper electrolytic solution.

[0082] S4. Use anti-electroplating glue to evenly apply around the welding wire mesh structure of the lower cover plate, put it into an oven and bake it at 60-80℃ for 30-60min to ensure complete curing, and then seal the back of the lower cover plate with epoxy resin tape to ensure that nano copper will not be deposited in the immersed copper electrolytic solution.

[0083] Use sodium hydroxide solution to remove oil stains on the surface of the lower cover and the screen structure, then rinse the residual sodium hydroxide on the surface with pure water, and then dry the surface moisture. Clean the surface of the pure copper plate 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.

[0084] Connect the copper plate to the positive pole of the power supply, and the negative pole of the power supply to the processed lower cover plate, and immerse both into the nano copper electrolytic solution prepared in S3. The solution temperature is controlled between 15 and 30°C to ensure complete immersion of the wire mesh structure.

[0085] Turn on the power supply to control the current density on the surface of the submerged part of the lower cover to 5-8A / cm 2 , nano copper can be electrodeposited on the wire mesh structure. After a certain period of deposition, nano copper with a thickness of 30 to 80 μm can be deposited. The porous nano copper and wire mesh structure images after electrodeposition for 5s, 15s, 30s, 40s, and 50s are shown in the figure below. Figure 7 , Figure 8 , Fig. 9 , Fig.10 , Fig.11 shown.

[0086] S5. Take out the electroplated screen structure and lower cover plate and immerse them in ultrapure water for 10 to 20 minutes to clean the residual nano copper electrolytic solution on the screen surface. After drying, remove the protective anti-electroplating glue and epoxy resin tape.

[0087] Then, the product is placed in a muffle furnace and nitrogen is introduced as a protective gas for calcination. The temperature is raised to 400-500° C. within 20-40 minutes and maintained at the temperature for 60-90 minutes. After 60-120 minutes, the temperature is lowered to room temperature to obtain a solidified secondary structure porous liquid wick structure.

[0088] Prolonging the calcination time will make the surface of the wire mesh nano-copper structure more completely solidified, such as Fig.12 shown.

[0089] Here, a capillary suction device is used to conduct a capillary suction experiment on a secondary structure porous wick. Figures 13-14 It can be seen that the prepared absorbent core has excellent absorbent capacity and good absorbent rate.

[0090] S6. The lower cover plate that has been cured and calcined is polished with sandpaper around the secondary structure porous liquid absorbent core until it is smooth and flat. The upper cover plate has an integrated stamping support column and is packaged by a laser welding machine.

[0091] Liquid is injected through the injector as the working medium of the vapor chamber. The volume of the liquid accounts for 10-70% of the entire packaged ultra-thin vapor chamber. The commonly used working medium is composed of one or more of ultrapure water, ethanol, acetone and salt solution. After completion, it is placed in a low-temperature environment for freezing treatment to ensure the subsequent use of a vacuum degassing machine to complete the vacuuming and sealing of the vapor chamber. Finally, the redundant vapor chamber sealing part is cut and re-sealed through a secondary degassing packaging machine, thereby obtaining an ultra-thin vapor chamber with a secondary structure porous liquid absorbent core. The specific structure is as follows: Figure 2 shown.

[0092] Embodiment 2:

[0093] like Figure 3 The figure shows the overall structure of a conventional heat spreader with a secondary structure porous liquid absorbent core, which is composed of an upper cover plate, a lower cover plate, a support column and a secondary structure porous liquid absorbent core.

[0094] like Figure 5 As shown, the preparation method thereof comprises the following steps:

[0095] S1. Pre-processing of stamping of upper and lower cover plates.

[0096] Same as Example 1.

[0097] S2. Cover plate welding wire mesh processing.

[0098] Same as Example 1.

[0099] S3. Prepare nano copper electrolytic solution.

[0100] Same as Example 1.

[0101] S4, electroplating to generate wire mesh nano copper.

[0102] Same as Example 1.

[0103] S5, calcining and solidifying the wire mesh nano-copper.

[0104] Same as Example 1.

[0105] S6. Grind the surroundings and back of the calcined lower cover plate welding wire mesh clean, and weld the upper cover plate to the corresponding lower cover plate welding point position with the support column required by the conventional heat sink.

[0106] Then the lower cover plate and the upper cover plate are sealed and welded. The subsequent liquid injection, degassing and sealing welding are the same as in Example 1. After completing the sealing and cutting of the excess part, a conventional heat spreader with a secondary structure porous liquid wick can be obtained. The internal structure is as follows Figure 4 shown.

[0107] 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 vapor chamber with a porous liquid wick having a secondary structure, characterized in that: The following steps are involved: Prepare the upper and lower covers; Cutting the metal wire mesh to obtain a wire mesh structure, and fixing the wire mesh structure on the inner surface of the lower cover plate; Electroplating is performed on the wire mesh structure of the lower cover plate to deposit nano copper; Calcination and solidification of the secondary structure of the wire mesh after electroplating nano copper; The upper cover plate and the calcined lower cover plate are packaged, and then subjected to liquid injection, degassing, sealing welding and packaging processes to obtain the heat spreader.

2. The preparation method according to claim 1, characterized in that: During the electroplating process, the temperature of the electrolytic solution is 15-30°C, and the current density is 5-8A / cm 2 , the electroplating time is 10 to 50S.

3. The preparation method according to claim 2, characterized in that: The molar ratio of CuSO4 to H2SO4 in the electrolytic solution is (0.3-0.5):(1-2).

4. The preparation method according to claim 1, characterized in that: The deposition thickness of the nano copper on the wire mesh structure is 30-80 μm.

5. The preparation method according to claim 1, characterized in that: The nano copper is calcined at a temperature of 400 to 500° C. and for a time of 60 to 90 minutes.

6. The preparation method according to claim 5, characterized in that: After the nano copper is calcined, the temperature is lowered to 20-25° C. over 60-120 minutes.

7. The preparation method according to claim 1, characterized in that: The mesh number of the wire mesh structure is 100 to 300 meshes.

8. The preparation method according to claim 1, characterized in that: Before electroplating the screen structure on the lower cover plate, the front area of ​​the lower cover plate located around the screen structure, as well as the back side and surrounding side walls of the lower cover plate are sealed.

9. The preparation method according to claim 1, characterized in that: After the nano copper is electroplated on the wire mesh structure, the electroplated wire mesh structure and the lower cover plate are firstly cleaned and dried, and then the secondary structure of the wire mesh after the nano copper is electroplated is calcined and solidified.

10. A vapor chamber obtained by the method for preparing a vapor chamber with a porous liquid-absorbing core having a secondary structure according to any one of claims 1 to 9.

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