Capillary wick and method of making same, and chip heat spreader

Abstract

The application discloses a capillary wick, a preparation method thereof and a chip radiator, and the capillary wick comprises a metal woven mesh, and an aluminum oxide film layer is arranged on the surface of the metal woven mesh; the metal woven mesh comprises a metal wire mesh layer, the metal wire mesh layer is woven by a plurality of metal wires with different wire diameters, and the metal wires are aluminum wires or aluminum alloy wires. The capillary wick in the application is provided with an aluminum oxide film layer on the surface of the metal woven mesh, the surface of the aluminum oxide film layer is microporous, the porous surface is helpful for the separation of bubbles or droplets when the capillary wick in the application is applied to a liquid cooling phase change type chip radiator, and the phase change heat exchange capacity is improved; the aluminum wires and the aluminum alloy wires have the characteristics of light weight and high yield strength, the thin and light capillary wick is realized by using the aluminum wires or the aluminum alloy wires, and the chip thermal management is developed towards the thin and light direction.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of capillary wicking, in particular to a capillary wicking, a preparation method thereof and a chip radiator. BACKGROUND

[0002] With the commercial operation of 5G network, electronic consumer products such as smart phones, ipads, notebook computers and other electronic products are rapidly iterated, and the lightweight, thin and flexible design of electronic consumer products gradually becomes an objective requirement of user experience. Of course, the thin and lightweight design also puts higher challenges on chip thermal management. Chip heat dissipation not only affects its running speed and stability, user experience, but also fatally affects its service life. Looking at the chip heat dissipation management, it has experienced the development of key technologies such as metal material heat conduction, heat pipe, graphite material, liquid cooling heat dissipation (two-phase flow latent heat vapor chamber), and the application of phase change latent heat technology has become the mainstream of current heat dissipation design. At present, the existing chip radiator cannot meet the demand of thin and lightweight design of chip thermal management while ensuring the heat dissipation effect. In addition, the heat dissipation effect of the existing chip radiator still needs to be improved. SUMMARY

[0003] The purpose of the present application is to overcome the above-mentioned shortcomings, and provide a capillary wicking. By setting an aluminum oxide film layer on the surface of the metal woven mesh, the surface of the aluminum oxide film layer is microporous, so that when the capillary wicking in the present application is applied to a liquid cooling phase change chip radiator, the porous surface helps the separation of bubbles or droplets, thereby improving the phase change heat transfer capacity. In addition, the present application also provides a preparation method of the capillary wicking and a chip radiator.

[0004] To achieve the above-mentioned purpose, the first aspect of the present application provides a capillary wicking, comprising a metal woven mesh, wherein the surface of the metal woven mesh is provided with an aluminum oxide film layer; the metal woven mesh comprises a metal wire mesh layer, the metal wire mesh layer is woven by a plurality of metal wires with different wire diameters, and the metal wires are aluminum wires or aluminum alloy wires.

[0005] By adopting the above technical scheme, by setting an aluminum oxide film layer on the surface of the metal woven mesh, the surface of the aluminum oxide film layer is microporous, so that when the capillary wicking in the present application is applied to a liquid cooling phase change chip radiator, the porous surface helps the separation of bubbles or droplets, thereby improving the phase change heat transfer capacity. The aluminum wires and aluminum alloy wires have the characteristics of light weight and high yield strength, and the use of aluminum wires or aluminum alloy wires realizes the thinness and lightness of the capillary wicking, which helps the chip thermal management to develop towards thinness and lightness.

[0006] Further, the thickness of the aluminum oxide film layer is 20-200 μm.

[0007] Further, the aluminum oxide film layer comprises a porous layer and a barrier layer, the barrier layer is located between the metal woven mesh and the porous layer, both the porous layer and the barrier layer are aluminum oxide film layers; the thickness of the porous layer is greater than the thickness of the barrier layer; the porous layer has a plurality of micropores A, and the barrier layer has a plurality of micropores B, the pore of the micropore A is greater than the pore of the micropore B.

[0008] Further, the pore diameter of the micropore A is 100-300 nm, and the pore diameter of the micropore B is 100-300 nm.

[0009] Further, the metal wire is a flat strip structure, the width of the metal wire is 20-150 μm, and the pore diameter of the mesh hole of the metal wire mesh layer is 20-200 μm.

[0010] Further, the cross section of the metal wire is circular, the wire diameter of the metal wire is 20-150 μm, and the pore diameter of the mesh hole of the metal wire mesh layer is 20-200 m.

[0011] The second application of the application provides a preparation method of the above-mentioned capillary liquid wick, comprising the following steps: surface treatment is performed on the surface of the metal woven mesh to form an oxide film layer on the surface, and the capillary liquid wick is obtained.

[0012] Further, the surface treatment method is any one of an anodization method, a solution immersion method, a magnetron sputtering method, an atomic layer deposition method, an electrochemical deposition method, a surface spraying method, and a vacuum evaporation method.

[0013] The third aspect of the application provides a chip heat sink, comprising a metal pipe body which is closed at both ends, and the capillary liquid wick described above; the two ends of the metal pipe body in the axial direction are respectively an evaporation end and a condensation end, the evaporation end is in heat transfer connection with a chip, and the condensation end is in heat transfer connection with an external heat dissipation environment; the inner cavity of the metal pipe body is a heat dissipation channel, the extension direction of the heat dissipation channel is consistent with the axial direction of the metal pipe body; the heat dissipation channel is in a vacuum state, the heat dissipation channel is provided with a liquid phase change working medium, and the inner wall surface of the heat dissipation channel is provided with the capillary liquid wick.

[0014] Further, a plurality of heat dissipation fins are arranged outside the condensation end.

[0015] Compared with the prior art, the application has the following beneficial effects:

[0016] 1. The capillary wick in the application is provided with an aluminum oxide film layer on the surface of the metal woven mesh, and the surface of the aluminum oxide film layer is microporous, so that the capillary wick in the application is applied to a liquid cooling phase change chip radiator, the porous surface helps the separation of bubbles or droplets, and the phase change heat transfer capacity is improved; the aluminum wire and the aluminum alloy wire have the characteristics of light weight and high yield strength, the use of aluminum wire or aluminum alloy wire realizes the thinness and lightness of the capillary wick, and helps the chip thermal management to develop towards thinness and lightness.

[0017] 2. The chip radiator in the application adopts the scheme of providing the capillary wick with an aluminum oxide film layer on the surface in the metal pipe body closed at both ends, has the characteristics of higher heat dissipation efficiency, realizes thinness and lightness at the same time, and helps the electronic products such as smart phones, ipads and notebook computers to develop towards thinness and lightness. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a structure schematic view of the capillary wick in embodiment 1.

[0019] Figure 2 It is a structure schematic view of the aluminum oxide film layer in embodiment 1.

[0020] Figure 3 It is an SEM analysis diagram of the aluminum oxide film layer in embodiment 1.

[0021] Figure 4 It is a structure schematic view of the metal wire mesh layer in embodiment 1.

[0022] Figure 5 It is a structure schematic view of the metal wire mesh layer in embodiment 2.

[0023] Figure 6 It is a structure schematic view of the chip radiator in embodiment 3.

[0024] The correspondence between each mark and component name is as follows:

[0025] Metal woven mesh 1, metal wire mesh layer 2, aluminum oxide film layer 3, porous layer 4, barrier layer 5, metal wire 6, metal pipe body 7, evaporation end 8, condensation end 9, heat dissipation channel 10, capillary wick 11, heat dissipation fin 12. DETAILED DESCRIPTION

[0026] In order to make the technical means for implementing the application, for the purpose of the embodiments of the present application, the technical solutions and advantages are clearer, the technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0028] It should be noted that: similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0029] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship of the product in use, only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present application, it should also be noted that unless otherwise explicitly specified and limited, the terms "set", "mount", "connect" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the communication inside two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] Example 1

[0032] Reference Figure 1 And Figure 3As shown, the embodiment provides a capillary wick, which comprises a metal woven mesh 1, and the surface of the metal woven mesh 1 is provided with an aluminum oxide film layer 3; the metal woven mesh 1 comprises a metal wire mesh layer 2, the metal wire mesh layer 2 is woven by a plurality of metal wires 6 with different diameters, and the metal wires 6 are aluminum wires or aluminum alloy wires. The metal wire mesh layer 2 can be woven in parallel, staggered, single layer, multi-layer and the like. The metal wire mesh layer 2 woven by the metal wires 6 with different diameters can significantly improve the capillary force of the capillary wick, especially for long-distance capillary return design, and has good heat exchange effect.

[0033] In the above, the metal woven mesh 1 can also comprise a plurality of metal wire mesh layers 2, and by arranging the plurality of metal wire mesh layers 2, the capillary porosity and water content of the capillary wick can be effectively improved, thereby increasing the equivalent latent heat capacity of the capillary wick 11.

[0034] For the metal wires 6, the materials of the plurality of metal wires 6 can be completely same or different.

[0035] Specifically, the thickness of the aluminum oxide film layer 3 in the embodiment is 20-200 μm.

[0036] Specifically, referring to Figure 2 As shown, the aluminum oxide film layer 3 in the embodiment comprises a porous layer 4 and a barrier layer 5, the barrier layer 5 is located between the metal woven mesh 1 and the porous layer 4, and the porous layer 4 and the barrier layer 5 are aluminum oxide film layers 3; the thickness of the porous layer 4 is greater than that of the barrier layer 5; the porous layer 4 has a plurality of micropores A, the barrier layer 5 has a plurality of micropores B, and the pore of the micropore A is greater than that of the micropore B.

[0037] Specifically, the pore diameter of the micropore A in the embodiment is 100-300 nm, and the pore diameter of the micropore B is 100-300 nm.

[0038] Referring to Figure 4 As shown, the metal wire 6 in the embodiment is in a flat strip structure, the width of the metal wire 6 is 20-150 μm, and the pore diameter of the mesh hole of the metal wire mesh layer 2 is 20-200 μm. Of course, the above parameters are not limited to the range of the listed sizes. In addition, the widths of the plurality of metal wires 6 can be completely same or different.

[0039] The preparation method of the capillary wick in the embodiment comprises the following steps: surface treatment is performed on the surface of the metal woven mesh 1 to form an oxide film layer on the surface, and the capillary wick is obtained.

[0040] Specifically, the aluminum oxide film 3 can be obtained by any one of the following methods: anodic oxidation, solution immersion, magnetron sputtering, atomic layer deposition, electrochemical deposition, surface spraying, and vacuum evaporation. However, it should be noted that the aluminum oxide film 3 is not limited to the processes listed above.

[0041] In this embodiment, the capillary wick has an aluminum oxide film layer 3 on the surface of the metal braided mesh 1. The surface of the aluminum oxide film layer 3 is micro-nano porous, which makes the capillary wick of this invention easier for bubbles or droplets to detach when applied to liquid-cooled phase change chip heat sinks, thereby improving the phase change heat transfer capacity. Aluminum wire and aluminum alloy wire are lightweight and have high yield strength. The use of aluminum wire or aluminum alloy wire realizes the thinning and lightweighting of the capillary wick, which helps the chip thermal management to develop towards thinner and lighter designs.

[0042] Example 2

[0043] This embodiment discloses a capillary suction core. The structural difference between the capillary suction core in this embodiment and the capillary suction core in Embodiment 1 is that the cross-section of the metal wire 6 in this embodiment is circular (refer to...). Figure 5 As shown, the diameter of the metal wire 6 is 20–150 μm, and the mesh size of the metal wire mesh layer 2 is 20–200 μm. Of course, the parameters above are not limited to the listed size range. In addition, the diameters of multiple metal wires 6 can be exactly the same or different.

[0044] Example 3

[0045] Reference Figure 6 As shown, this embodiment discloses a chip heat sink, including a metal tube 7 that is closed at both ends, and a capillary wick 11 disclosed in Embodiment 1; the two ends of the metal tube 7 in the axial direction are an evaporation end 8 and a condensation end 9, respectively. The evaporation end 8 is connected to the chip for heat transfer, and the condensation end 9 is connected to the external heat dissipation environment for heat transfer; the inner cavity of the metal tube 7 is a heat dissipation channel 10, and the extension direction of the heat dissipation channel 10 is consistent with the axial direction of the metal tube 7; the inside of the heat dissipation channel 10 is in a vacuum state, the heat dissipation channel 10 is provided with a liquid phase change working medium, and the inner wall surface of the heat dissipation channel 10 is provided with a capillary wick 11.

[0046] The chip heat sink in this embodiment features higher heat dissipation efficiency, as well as a thinner and lighter design, making it widely applicable to smartphones, iPads, laptops, and other devices, thus improving the user experience. Furthermore, the thinner and lighter design can be further enhanced by using a metal tube 7 made of stainless steel, aluminum, or aluminum alloy.

[0047] When the chip heat sink in the embodiment is used, the liquid phase change working medium fills the capillary wick 11. When the evaporation end 8 is heated, the working fluid in the capillary wick 11 evaporates and vaporizes to form steam. The steam flows to the condensation end 9 under the action of a small pressure difference. In the process of flowing to the condensation end 9, the steam condenses into liquid phase change working medium and releases heat. The liquid phase change working medium flows back to the evaporation end 8 along the capillary wick 11 under the action of the capillary force generated by the combination of the capillary wick 11 and the liquid. The cycle is repeated to realize heat dissipation.

[0048] Further, the condensation end 9 in the embodiment is provided with a plurality of heat dissipation fins 12 on the outside. When the chip heat sink in the embodiment is used, heat is continuously transmitted from the evaporation end 8 of the metal pipe body 7 to the condensation end 9. The heat transmitted to the condensation end 9 is conducted to the heat dissipation fins 12 to realize rapid heat dissipation.

[0049] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A capillary wick, characterized in that The metal woven net is provided with an aluminum oxide film layer on the surface, and the metal woven net comprises a metal wire mesh layer woven by a plurality of metal wires with different diameters, and the materials of the metal wires with different diameters are different. The thickness of the aluminum oxide film layer is 20-200 μm, the aluminum oxide film layer comprises a porous layer and a barrier layer, the barrier layer is located between the metal woven net and the porous layer, and the porous layer and the barrier layer are both aluminum oxide film layers; the thickness of the porous layer is greater than that of the barrier layer. The porous layer has a plurality of micropores A, and the barrier layer has a plurality of micropores B; the micropores A have larger apertures than the micropores B. The micropores A have a pore diameter of 100-300 nm, and the micropores B have a pore diameter of 100-300 nm.

2. The capillary wick of claim 1, wherein, The metal wires have a flat strip structure, the width of the metal wires is 20-150 μm, and the mesh holes of the metal wire mesh layer have a pore diameter of 20-200 μm.

3. The capillary wick of claim 1, wherein, The cross section of the metal wires is circular, and the diameter of the metal wires is 20-150 μm.

4. A method of manufacturing a capillary wick according to any one of claims 1 to 3, characterized in that, The method comprises the following steps: The surface of the metal woven net is treated to form an oxidation film layer on the surface, thereby obtaining a capillary liquid wick.

5. The method of claim 4, wherein the capillary wick is prepared by The surface treatment method is any one of an anodic oxidation method, a solution immersion method, a magnetron sputtering method, an atomic layer deposition method, an electrochemical deposition method, a surface spraying method, and a vacuum evaporation method.

6. A chip heat spreader characterized by, The metal tube body is closed at both ends, and further comprises the capillary liquid wick according to any one of claims 1-4; the two ends of the metal tube body in the axial direction are respectively an evaporation end and a condensation end, the evaporation end is in heat transfer connection with a chip, and the condensation end is in heat transfer connection with an external heat dissipation environment; the inner cavity of the metal tube body is a heat dissipation channel, the extension direction of the heat dissipation channel is consistent with the axial direction of the metal tube body; the heat dissipation channel is in a vacuum state, the heat dissipation channel is provided with a liquid phase change working medium, and the inner wall surface of the heat dissipation channel is provided with the capillary liquid wick; The condensation end is provided with a plurality of heat dissipation fins on the outside.

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