Heat dissipation structure, electronic device, and manufacturing method thereof

Abstract

To provide a heat dissipation structure, an electronic device, and a manufacturing method thereof that can prevent a decrease in the heat transfer performance between a heat-generating electrical component and a heat dissipator, and can maintain the surface of the electrical component in a suitable condition.SOLUTION: A heat dissipation structure 60 includes a metal mesh 64 that contacts the surface of a die 46, and a heat receiving plate 72 that holds the mesh 64 between the heat receiving plate and the surface of the die 46. The mesh 64 is impregnated with liquid metal 70 at least in the portion that contacts the surface of the die 46, and intersections 96 of vertical and horizontal strands 90 are crushed in a thickness direction. The mesh 64 has flat portions 90a formed on the surface side of the strands 90 at the intersections 96.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a heat dissipation structure for a heat-generating electrical component, an electronic device equipped with the heat dissipation structure, and a method for manufacturing the same. [Background technology]

[0002] Portable information devices such as notebook PCs are equipped with semiconductor chips such as CPUs and GPUs. The CPU and GPU have a shape that includes a substrate, which is the part to be mounted on a board, and a rectangular die provided on the surface of the substrate.

[0003] Semiconductor chips such as CPUs and GPUs are heat generating bodies, and depending on their power consumption (especially under high load), heat needs to be dissipated. As a means for dissipating heat from a CPU or GPU, a heat dissipator such as a vapor chamber, heat spreader, or heat sink may be used, and the die may be brought into contact with the surface of the die via such a heat dissipator to dissipate heat. In some cases, a fluid such as liquid metal or thermally conductive grease may be interposed between the die and the heat dissipator to efficiently transfer heat (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-146819 A Summary of the Invention [Problem to be solved by the invention]

[0005] Liquid metal has higher thermal conductivity than thermal grease and can effectively transfer heat from the die to the heat sink. On the other hand, liquid metal has the characteristic of being more fluid than thermal grease. When electronic devices are carried around, they are prone to vibration and shock. In that case, there is a concern that the fluid liquid metal may leak out from the gap between the die and the heat sink due to the repeated forces it receives from the die and the heat sink.

[0006] Liquid metal may contain gallium as its main component, which may cause a chemical reaction with copper or solder. In addition, liquid metal is conductive, so if it leaks and touches nearby electrical elements such as capacitors, it will cause a short circuit, so some kind of countermeasure is necessary.

[0007] Therefore, the inventors of the present application have been considering providing a metal mesh impregnated with liquid metal between a heat generating body such as a semiconductor chip and a heat sink such as a vapor chamber, and the liquid metal impregnated in the metal mesh is maintained with almost no leakage.

[0008] Incidentally, since the wires are woven in all directions in the metal mesh, the intersections of the wires form small protrusions, which may slightly scratch the surface of the die that they come into contact with.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a heat dissipation structure, an electronic device, and a manufacturing method thereof that can prevent a decrease in heat transfer performance between a heat-generating electrical component and a heat sink, and further can maintain the surface of the electrical component in an optimal condition. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems and achieve the object, a heat dissipation structure according to a first embodiment of the present invention is a heat dissipation structure for a heat-generating electrical component, comprising a metal mesh abutting a surface of the electrical component and a heat sink sandwiching the metal mesh between the surface of the electrical component, wherein the metal mesh is impregnated with a heat conductive fluid at least in the portion abutting the surface of the electrical component, and the intersections of the vertical and horizontal wires are crushed in the thickness direction.

[0011] An electronic device according to a second aspect of the present invention is an electronic device equipped with a heat-generating electrical component, comprising a metal mesh in contact with a surface of the electrical component, and a heat sink sandwiching the metal mesh between the surface of the electrical component, wherein the metal mesh is impregnated with a heat conductive fluid at least in the portion in contact with the surface of the electrical component, and the intersections of the vertical and horizontal wires are crushed in the thickness direction.

[0012] A manufacturing method for an electronic device according to a third aspect of the present invention is a manufacturing method for an electronic device having a heat-generating electrical component, and includes the steps of pressing a metal mesh, impregnating the metal mesh with a heat-transferring fluid, and sandwiching the metal mesh between a surface of the electrical component and a heat sink. Effect of the Invention

[0013] According to the above-described aspect of the present invention, it is possible to prevent a decrease in the heat transfer performance between the heat-generating electrical component and the heat sink, and further, since the intersection points of the wires are crushed in the thickness direction, it is possible to maintain the surface of the electrical component in a suitable condition. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic plan view of an electronic device according to an embodiment viewed from above. [Diagram 2] FIG. 2 is a bottom view illustrating a schematic internal structure of the housing. [Diagram 3] FIG. 3 is a schematic exploded perspective view of a CPU, a heat transfer structure, and a sponge mounted on a motherboard. [Figure 4] FIG. 4 is an exploded perspective view of the heat dissipation structure. [Diagram 5] FIG. 5 is a perspective view of the heat dissipation structure. [Figure 6] FIG. 6 is a schematic cross-sectional side view of the heat dissipation structure. [Figure 7] FIG. 7 is an exploded perspective view of the heat transfer structure. [Figure 8]FIG. 8 is a cross-sectional view of the mesh and its surrounding area. [Figure 9] FIG. 9 is an enlarged plan view of the mesh. [Figure 10] FIG. 10 is a cross-sectional view of the mesh material. [Figure 11] FIG. 11 is a schematic diagram showing how a mesh is produced by rolling a mesh material. [Figure 12] FIG. 12 is a flowchart showing a part of a manufacturing method of an electronic device. [Figure 13] FIG. 13 is a perspective view of a heat dissipation structure covered with a protective film. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of a heat dissipation structure, an electronic device, and a manufacturing method thereof according to the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to these preferred embodiments.

[0016] Fig. 1 is a schematic plan view of an electronic device 10 according to an embodiment, seen from above. As shown in Fig. 1, the electronic device 10 is a clamshell notebook PC in which a display housing 12 and a housing 14 are connected by a hinge 16 so as to be relatively rotatable, and is a so-called mobile workstation. The electronic device according to the present invention may be, for example, a desktop PC, a tablet PC, a mobile phone, a smartphone, a game machine, or the like, other than a notebook PC.

[0017] The display housing 12 is a thin, flat box. A display 18 is mounted on the display housing 12. The display 18 is configured with, for example, an organic light emitting diode (OLED) or liquid crystal.

[0018] In the following, the housing 14 and each element mounted thereon will be described assuming that the housings 12, 14 are in an open state as shown in FIG. 1, and the posture for viewing the display 18 is used as the reference, with the front side being referred to as the front, the back side being referred to as the rear, the width direction being the left and right, and the height direction (thickness direction of the housing 14) being referred to as the top and bottom.

[0019] The housing 14 is a thin, flat box. The housing 14 is composed of a cover member 14A forming the upper surface and the four side surfaces, and a cover member 14B forming the lower surface. The upper cover member 14A has a substantially bathtub shape with an opening at the bottom. The lower cover member 14B has a substantially flat plate shape and serves as a lid that closes the opening at the bottom of the cover member 14A. The cover members 14A and 14B are stacked in the thickness direction and detachably connected to each other. A keyboard 20 and a touch pad 21 are provided on the upper surface of the housing 14. The rear end of the housing 14 is connected to the display housing 12 using a hinge 16.

[0020] Fig. 2 is a bottom view showing a schematic internal structure of the housing 14. In Fig. 2, the cover member 14B on the bottom surface is omitted to expose the inside. As shown in Fig. 2, a cooling module 22, a motherboard (substrate) 24, and a battery device 26 are provided inside the housing 14. Various electronic components, mechanical components, etc. are also provided inside the housing 14.

[0021] The motherboard 24 is a main board of the electronic device 10. The motherboard 24 is disposed toward the rear of the housing 14 and extends in the left-right direction. The motherboard 24 is a printed circuit board on which various electronic components such as a CPU (Central Processing Unit) 30, a GPU (Graphics Processing Unit) 31, a communication module, a memory, and a connection terminal are mounted. The motherboard 24 is disposed under the keyboard 20 and is screwed to the rear surface of the keyboard 20 and the inner surface of the cover member 14A. The upper surface of the motherboard 24 is the mounting surface for the cover member 14A, and the lower surface is the mounting surface for the CPU 30 and the like. The CPU 30 performs calculations related to the main control and processing of the electronic device 10. The GPU 31 performs calculations necessary for image depiction such as 3D graphics. The CPU 30 and the GPU 31 are disposed side by side in the approximate center of the mounting surface of the motherboard 24.

[0022] The battery device 26 is a rechargeable battery that serves as a power source for the electronic device 10. The battery device 26 is disposed in front of the motherboard 24, and extends left and right along the front end of the housing 14.

[0023] The CPU 30 and the GPU 31 are heat generating elements that generate the largest amount of heat among the electronic components mounted in the housing 14. Therefore, the cooling module 22 absorbs and diffuses the heat generated by the CPU 30 and the GPU 31, and further discharges it to the outside of the housing 14. The cooling module 22 is stacked on the lower surface of the motherboard 24.

[0024] The cooling module 22 includes a vapor chamber (heat dissipation body) 36, two heat pipes 38, 38, a pair of left and right cooling fins 40, 41, and a pair of left and right blower fans 42, 43.

[0025] The vapor chamber 36 is a plate-type heat transport device. The vapor chamber 36 is formed by forming a sealed space between two thin metal plates and sealing the working fluid in the sealed space. The metal plates are made of a metal with high thermal conductivity such as aluminum, copper, or stainless steel. The sealed space becomes a flow path through which the sealed working fluid flows while undergoing a phase change. Examples of the working fluid include water, alternative fluorocarbons, acetone, and butane. A wick is disposed in the sealed space to transport the condensed working fluid by capillary action. The wick is formed of a porous body such as a mesh made of thin metal wires woven into a cotton-like shape or a fine flow path. The vapor chamber 36 is reinforced by a frame 45 (see FIG. 4).

[0026] The heat pipes 38, 38 are pipe-type heat transport devices. In this embodiment, two heat pipes 38 are used in parallel in a pair, but one or three or more heat pipes may be used. The heat pipe 38 is a metal pipe that is crushed thin and flat to form an elliptical cross section, and a working fluid is sealed in a sealed space formed in the metal pipe. The metal pipe is made of a metal with high thermal conductivity such as aluminum, copper, or stainless steel. The sealed space becomes a flow path through which the sealed working fluid flows while undergoing a phase change. Examples of the working fluid include water, alternative fluorocarbons, acetone, and butane. A wick that transports the condensed working fluid by capillary action is disposed in the sealed space. The wick is made of a porous body such as a mesh made of thin metal wires woven into a cotton-like shape or a fine flow path.

[0027] The left cooling fins 40, 41 have a structure in which multiple plate-shaped fins are arranged at equal intervals in the left-right direction on the surface of a plate. Each fin stands upright in the up-down direction and extends in the front-rear direction. A gap is formed between adjacent fins to allow air sent from blower fans 42, 43 to pass through.

[0028] FIG. 3 is a schematic exploded perspective view of the CPU 30, the heat transfer structure 62, and the sponge 65 mounted on the motherboard 24. As shown in FIG.

[0029] The CPU 30 has a substrate 44 and a die 46. The substrate 44 is a thin plate-like portion mounted on the motherboard 24, and is a rectangle that is long in the left-right direction in a plan view. The die 46 is a portion that includes an arithmetic circuit, and is provided so as to protrude slightly from the surface of the substrate 44. The die 46 is a rectangle that is long in the left-right direction in a plan view, and is provided approximately in the center of the surface of the substrate 44. The CPU 30 is one of the components in the electronic device 10 that generates the most heat, and the die 46 generates the most heat among them.

[0030] Reinforcing ribs 48 are provided on the four periphery edges of the substrate 44. The ribs 48 are slightly lower than the die 46. The gap between the die 46 and the ribs 48 is slightly wider in the left-right direction but narrower in the front-back direction. A small element 50 such as a capacitor is provided on the surface of the substrate 44. The element 50 is covered with an insulating material 52. The insulating material 52 is, for example, an ultraviolet-curing coating material formed in a film shape. This coating material is applied so as to cover the element 50, and then hardened by irradiation with ultraviolet light to form the insulating material 52. The insulating material 52 can be easily formed by using an ultraviolet-curing coating material. The insulating material 52 may be another insulating adhesive or the like. Although the liquid metal 70 described later does not basically come into contact with the element 50, the reliability of the element 50 is further improved by covering the element 50 with the insulating material 52.

[0031] Next, a heat dissipation structure 60 according to the present embodiment will be described. Fig. 4 is an exploded perspective view of the heat dissipation structure 60. Fig. 5 is a perspective view of the heat dissipation structure 60. Fig. 6 is a schematic cross-sectional side view of the heat dissipation structure 60. Fig. 7 is an exploded perspective view of the heat transfer structure 62.

[0032] The heat dissipation structure 60 is intended to dissipate heat, particularly from the die (electrical component) 46 of the heat-generating CPU (electrical component, semiconductor chip) 30, and includes a heat transfer structure 62 and a sponge 65. The vapor chamber 36 also constitutes a part of the heat dissipation structure 60.

[0033] The heat transfer structure 62 has a mesh (metal mesh) 64 and sheet materials 66, 68 that sandwich both left and right ends of the mesh 64 from above and below. The heat transfer structure 62 is small and lightweight. The mesh 64 and the sheet materials 66, 68 are inexpensive.

[0034] The mesh 64 has a central rectangular heating element contact area 64a and a heating element non-contact area 64b that protrudes in the left-right direction from the heating element contact area 64a. Specifically, the mesh 64 is rectangular in shape, with the central portion corresponding to the heating element contact area 64a and the other portions corresponding to the heating element non-contact area 64b. At the boundary between the heating element contact area 64a and the heating element non-contact area 64b, a small step 64c corresponding to the thickness of the heat receiving plate 72 described later is formed.

[0035] The heating element contact area 64a is a portion that receives heat by contacting the surface of the die 46. At least the heating element contact area 64a of the mesh 64 is impregnated with liquid metal (thermal conductive fluid) 70 over substantially the entire surface. The heating element non-contact area 64b is basically not impregnated with liquid metal 70, which reduces costs by reducing the amount of liquid metal 70 used and also makes it easier for an adhesive 74, which will be described later, to be impregnated therein.

[0036] The liquid metal 70 is a metal that is primarily composed of, for example, gallium and is basically liquid at room temperature, but may be a phase change material that is liquid at least at temperatures in normal use when the motherboard 24 is energized and the CPU 30 is in operation. Since the liquid metal 70 is a metal, it has excellent thermal conductivity and electrical conductivity. Also, since the liquid metal 70 is liquid, it has fluidity.

[0037] The liquid metal 70 is basically impregnated over almost the entire surface of the heating element contact area 64a, and is in contact with the surfaces of the die 46 and the vapor chamber 36, providing good thermal connection between the two. The liquid metal 70 is basically impregnated over almost the entire surface of the heating element contact area 64a, but depending on the conditions, there may be some non-impregnated areas at the ends of the heating element contact area 64a to allow for the absorption of excess. Since the liquid metal 70 is impregnated and held in the mesh 64, it will not leak out into the surroundings even if it is subjected to a certain amount of vibration or impact.

[0038] The impregnation may be performed, for example, by immersing the mesh 64 in a tank of the liquid metal 70 or by applying the liquid metal 70 to the mesh 64. Although it may be difficult for the liquid metal 70 to impregnate the mesh 64, the mesh 64 is easy to handle as a standalone unit prior to being incorporated into the heat dissipation structure 60, and furthermore, six sides (top, bottom, front, back, left and right) are open, making it easy to impregnate the mesh 64 with the liquid metal 70. Furthermore, since the mesh 64 is a standalone unit at this stage, it is possible to inspect visually or by a prescribed means whether the mesh 64 is properly impregnated with the liquid metal 70.

[0039] The heating element contact area 64a is a rectangle having the same size as or slightly larger than the surface of the die 46, and covers the surface of the die 46. Small holes may be provided in the heating element contact area 64a depending on the heat distribution in the die 46, and the holes may serve as pools for the liquid metal 70.

[0040] The heating element contact area 64a impregnated with the liquid metal 70 is thermally connected to the vapor chamber 36 via a heat receiving plate 72. The heat receiving plate 72 is a metal plate such as copper, and can be regarded as a part of the vapor chamber 36 that essentially serves as a heat dissipator. The heat receiving plate 72 may be omitted.

[0041] The heating element non-contact area 64b is formed continuously in the left-right direction from the heating element contact area 64a, and the heating element non-contact area 64b does not contact the surface of the die 46.

[0042] The mesh 64 will be further described. Fig. 8 is a cross-sectional view of the mesh 64 and its surrounding area. Fig. 9 is an enlarged plan view of the mesh 64. The liquid metal 70 is omitted in Figs. 8 and 9. Fig. 10 is a cross-sectional view of a mesh material 92. Fig. 11 is a schematic diagram showing how the mesh material 92 is rolled to produce the mesh 64.

[0043] The mesh 64 is formed by weaving metal wires 90 vertically and horizontally, and is produced by rolling a mesh material 92 shown in FIG. 10 with a pair of rolling rollers 95 as shown in FIG. 11, crushing it in the thickness direction, and cutting it to a predetermined length. The thickness H0 of the mesh material 92 is twice the diameter of the wires 94, which have a substantially circular cross section. In contrast, the thickness H of the crushed mesh 64 is about 0.4 to 0.6 times the thickness H0, specifically, H0 is about 0.1 mm, and H is about 0.04 to 0.06 mm. With such a thickness H, the wires 90 become a moderately flat ellipse, and the flat portion 90a described below is reliably formed. In addition, since a certain degree of thickness is maintained, it is easy to impregnate with the liquid metal 70, and less liquid metal 70 is required compared to the mesh material 92.

[0044] The wires 90 of the mesh 64 are formed by crushing the wires 94 of the mesh material 92, and in particular, the intersections 96 of the vertical and horizontal directions are crushed, and the cross section is an approximately elliptical shape that is thin in the thickness direction. In addition, flat portions 90a are formed on the wires 90 at the intersections 96 of the mesh 64. The flat portions 90a are formed on the front and back sides of the mesh 64, in other words, on the side where the wires 90 abut against the die 46 or the heat receiving plate 72, and on the side opposite to the side where the wires 90 face each other. The flat portions 90a are formed by direct contact with the rolling roller 95, and are approximately elliptical in plan view (see FIG. 9). However, the flat portions 90a are not necessarily strictly flat for reasons of manufacturing accuracy, and may be slightly curved, and may be substantially flat to the extent that they can be distinguished from other surfaces as traces of contact with the rolling roller 95.

[0045] In this way, the cross section of the wire 90 that contacts the die 46 and the heat receiving plate 72 is a flattened, approximately elliptical shape that conforms to the surfaces of these contact objects, and has no localized protrusions, and the contact intersections 96 have flat portions 90a, so that an appropriate contact area is ensured, and the pressure is dispersed, and the surfaces of the die 46 and the heat receiving plate 72 can be maintained in a suitable state. In particular, the lid that forms the surface of the die 46 is made of ceramic or alloy, and may be easily scratched by protrusions, but the mesh 64 described above can maintain the surface in a suitable state. The mesh 64 can be easily formed by crushing the entire surface of the mesh material 92 by rolling as shown in Figure 11, but depending on the manufacturing conditions, it is sufficient that at least the intersections 96 of the vertical and horizontal wires 90 in the heating element contact area 64a are crushed in the thickness direction.

[0046] The mesh 64 is made of a metal material, and thus provides suitable heat transfer performance. When the mesh 64 is made of a metal material such as copper or aluminum, it is advisable to use a material plated with nickel (including an alloy mainly composed of nickel) or to subject the mesh to a prescribed anti-corrosion treatment. In other words, by making at least the surface of the mesh 64 out of nickel or subjecting it to an anti-corrosion treatment, it is possible to prevent the mesh 64 from being altered by the liquid metal 70. By making the mesh 64 out of nickel, the plating process can be omitted. Furthermore, by nickel plating copper or aluminum, suitable heat conductivity can be obtained.

[0047] Returning to Figs. 4 to 7, the sheet materials 66, 68 are, for example, thin resin film-like. The thickness of each of the sheet materials 66, 68 is, for example, about 0.05 mm. The pair of heat generating element non-contact range portions 64b are sandwiched between the pair of sheet materials 66, 68. The sheet materials 66 and 68 are the same, but here, the side that is attached to the vapor chamber 36 is the sheet material 68, and the opposite side is the sheet material 66. The sheet materials 66, 68 are overlapped, and a part of them sandwich the end of the heat generating element non-contact range portion 64b so as to surround three sides (up and down directions and right or left). The sheet materials 66, 68 have a suitable area and can be reliably fixed to the vapor chamber 36 by an adhesive tape 76 described later. The liquid metal 70 is not basically impregnated into the heating element non-contact area 64b, but even if it seeps out from the heating element contact area 64a and penetrates into the heating element non-contact area 64b, it will not leak out any further because the three sides are covered with the sheet materials 66, 68.

[0048] The sheet materials 66, 68 and the mesh 64, and the sheet materials 66, 68 are fixed together with an adhesive 74. The layer of adhesive 74 between the sheet materials 66, 68 is sufficiently thin. The adhesive 74 is appropriately impregnated into the non-heating element contact area 64b of the mesh 64, and high adhesive strength is obtained. Depending on the design conditions, the non-heating element contact area 64b may be almost entirely covered with the sheet materials 66, 68, or a portion close to the heating element contact area 64a may be somewhat exposed.

[0049] The sheet material 68 and the vapor chamber 36 are fixed with an adhesive tape (adhesive material) 76. The adhesive tape 76 fixes the heat transfer structure 62 to the vapor chamber 36 with a moderate adhesive force, but can be removed as necessary for maintenance, etc. The thickness of the adhesive tape 76 is, for example, about 0.05 mm. Depending on the design conditions, a portion of the overlapped sheet materials 66, 68 may be attached on top of the frame 45 (see FIG. 4) or may be inserted under the frame 45.

[0050] The sponge 65 has a frame shape and closes the gap between the vapor chamber 36 and the substrate 44 around the die 46. A part of the sponge 65 abuts against the vapor chamber 36 through a portion of the sheet materials 66, 68 that does not overlap with the mesh 64. That is, the sponge 65 is provided so as to surround the mesh 64 in a plan view. Although the liquid metal 70 does not basically come into contact with the electrical components mounted on the motherboard 24, by partitioning the four periphery of the substrate 44 with the sponge 65, the liquid metal 70 is further prevented from leaking out to the surroundings. In addition, the sponge 65 is provided between the rib 48 and the vapor chamber 36 and fixed with an adhesive. This allows the thickness of the sponge 65 to be thin and stable.

[0051] Next, a description will be given of a part of a manufacturing method of the electronic device 10. Fig. 12 is a flow chart showing a part of the manufacturing method of the electronic device 10.

[0052] In the assembly process of the heat dissipation structure 60, the first manufacturer first rolls the mesh material 92 (see FIG. 11), and then cuts it to a predetermined length to obtain the mesh 64 (step S1). However, depending on the manufacturing conditions, the method of crushing the mesh material 92 is not limited to the rolling process, and other pressing means may be used. The nickel plating or anti-corrosion treatment may be performed either before or after the rolling process. The mesh 64 is bent so as to be divided into a heating element contact area 64a and a heating element non-contact area 64b (see FIG. 7).

[0053] Next, the first manufacturer assembles the heat transfer structure 62. Here, as shown in Fig. 7, the heat-generating-element non-contact areas 64b at both ends of the mesh 64 are sandwiched between the sheet materials 66, 68, and fixed with the adhesive material 74 as described above (step S2). An adhesive tape 76 is attached to the surface of the sheet material 68 opposite to the sheet material 66. In addition, a release paper 78 is attached to the surface of the adhesive tape 76 opposite to the sheet material 68 to protect the adhesive surface. The thickness of the release paper 78 is, for example, about 0.1 mm. One sheet of release paper 78 may be provided across the two sheet materials 68, or two sheets may be provided individually for the two sheet materials 68.

[0054] The first manufacturer further impregnates the heating element contact area 64a of the mesh 64 with liquid metal 70 (step S3). The timing of impregnation with the liquid metal 70 is, for example, after the heating element non-contact area 64b is sandwiched between the sheet materials 66 and 68. The heat transfer structure 62 assembled by the first manufacturer is supplied to the second manufacturer. Such a heat transfer structure 62 can be handled as one component and is portable. If one release paper 78 is provided across the two sheet materials 68, the release paper 78 can protect one side of the heating element contact area 64a impregnated with the liquid metal 70 when the heat transfer structure 62 is transported alone. A separate protective film may be provided on the other side of the heating element contact area 64a for transport.

[0055] The second manufacturer is a company that assembles the cooling module 22, and removes the release paper 78 from the supplied heat transfer structure 62, attaches the sheet material 68 with the adhesive tape 76 attached to a predetermined position in the vapor chamber 36 as shown in FIG. 4, and further attaches the sponge 65 (step S4). The heat dissipation structure 60 (see FIG. 5) assembled by the second manufacturer in this way is covered with a protective film 80 as shown in FIG. 13. The cooling module 22 including the heat dissipation structure 60 assembled by the second manufacturer is supplied to a third manufacturer. Since the heat dissipation structure 60 is incorporated into the cooling module 22 in this way, it can be handled as one with the cooling module 22.

[0056] The third manufacturer is a manufacturer that assembles the electronic device 10, and removes the protective film 80 from the supplied cooling module 22 and attaches it to a predetermined position in the housing 14 as shown in Fig. 2. As a result, the heating element contact area 64a of the mesh 64 in the heat transfer structure 62 is sandwiched between the surface of the die 46 and the vapor chamber 36 and contacts both of them (step S5). Since the heating element contact area 64a is impregnated with the liquid metal 70, the thermal resistance between the die 46 and the vapor chamber 36 becomes sufficiently small.

[0057] In addition, the third manufacturer can handle the cooling module 22 including the heat dissipation structure 60 as a single component, and can install it in the housing 14 by a simple operation such as screwing. Furthermore, since the third manufacturer basically does not need to handle the liquid metal 70, no storage device or application device for the liquid metal 70 is required, which is suitable for mass production assembly.

[0058] Furthermore, when it becomes necessary to replace the heat transfer structure 62 during repair or maintenance of the electronic device 10, a worker can simply reattach a replacement heat transfer structure 62, and there is no need to transport the electronic device 10 to a facility that has a storage device or application device for the liquid metal 70. Therefore, the repair work location, service base, etc. are not limited.

[0059] The heat transfer structure 62 containing the liquid metal 70 is removed together with the cooling module 22 or vapor chamber 36 during repair, so that the heat transfer structure 62 does not remain on the CPU 30 by itself, there is no scattering of the liquid metal 70, and it is easy to handle.

[0060] In the heat dissipation structure 60, heat transfer structure 62, and electronic device 10 described above, the liquid metal 70 is impregnated into the heating element contact area 64a of the mesh 64, so that leakage to the surroundings is prevented, and furthermore, the action of the liquid metal 70 can prevent a decrease in the heat transfer performance between the die 46 and the vapor chamber 36. Also, the heating element contact area 64a is sandwiched between the die 46 and the heat receiving plate 72 and is stable to a certain extent, but the heating element non-contact areas 64b at both ends are fixed to the vapor chamber 36 via the sheet materials 66, 68, respectively, so that the mesh 64 can be further prevented from shifting in position. The mesh 64 is somewhat hard and is not suitable for direct fixing to the vapor chamber 36, but it can be suitably fixed to the vapor chamber 36 by securing an appropriate area with the flexible sheet materials 66, 68.

[0061] The pair of heat-generating-element non-contact ranges 64b are sandwiched between a pair of sheet materials 66, 68, respectively, and therefore are strong and unlikely to come off, particularly when the heat-transfer structure 62 is transported or attached as a single unit. However, depending on design conditions, the sheet material 68 may be omitted and the heat-transfer structure 62 may be fixed to the vapor chamber 36 by the sheet material 66 alone. The sheet materials 66, 68 sandwich the end of the heat-generating-element non-contact ranges 64b so as to surround three sides, but depending on design conditions, they may surround only the left-right direction or only the front-rear direction.

[0062] The heat transfer structure 62 can be applied to various dies 46 as long as the heating element contact area 64a has a suitable area, and since there is no particular restriction on the fixed side vapor chamber 36, it is highly versatile. The mesh 64 constituting the heat transfer structure 62 is a strip-shaped structure consisting of the heating element contact area 64a and the heating element non-contact area 64b on both sides thereof, and therefore can be suitably applied to the horizontally elongated CPU 30 and die 46 in particular. In the CPU 30 of the above example, the vertical distance between the edge of the die 46 and the rib 48 is small, but the horizontal distance is relatively large, and by arranging the strip-shaped mesh 64 along the horizontal direction, the rib 48 is unlikely to interfere with the sheet materials 66, 68, and the space is effectively utilized. The heat dissipation structure 60 and the heat transfer structure 62 can also be applied to heat-generating electrical components other than the CPU 30 (e.g., the GPU 31).

[0063] The fluid impregnated into the mesh 64 is not limited to the liquid metal 70, and may be other heat-conductive fluids such as heat-conductive grease. The heat-conductive fluid in this application is not limited to liquids, but refers to semi-solids, viscous bodies, and other fluids that have fluidity, including greases and oil compounds.

[0064] The present invention is not limited to the above-described embodiment, and can of course be freely modified without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0065] 10 Electronic equipment 14. Chassis 22 Cooling module 24 Motherboard (circuit board) 30 CPU (electrical components) 36 Vapor chamber (heat sink) 38 Heat Pipe 44 Substrate 46 Die (Electrical Parts) 48 Ribs 60 Heat dissipation structure 62 Heat Transfer Structure 64 mesh (metal mesh) 64a Heating element contact area 64b Heating element non-contact area 65 Sponge 66,68 Sheet material 70 Liquid metal (heat transfer fluid) 72 Heat receiving plate (heat sink) 74 Adhesive 76 Adhesive Tape 78 Release paper 80 Protective film 90 Wire 90a flat part 92 Mesh Material 94 Wire 96 Intersections

Claims

1. A heat dissipation structure for a heat-generating electrical component, comprising: a metal mesh abutting a surface of the electrical component; a heat sink that holds the metal mesh between the heat sink and a surface of the electrical component; having The metal mesh is impregnated with a heat conductive fluid at least in the portion that contacts the surface of the electrical component, and the intersections of the vertical and horizontal wires are crushed in the thickness direction. A heat dissipation structure characterized by:

2. The heat dissipation structure according to claim 1 , The metal mesh has a flat portion formed on the side where the wires come into contact with the electrical component or the heat sink at the intersection. A heat dissipation structure characterized by:

3. The heat dissipation structure according to claim 1 , The metal mesh is a heat-transferring element contact area having a central portion impregnated with a heat-transfer fluid and contacting a surface of the electrical component to receive heat; a pair of heating element non-contact areas extending continuously from both sides of the heating element contact area and not in contact with a surface of the electrical component; Equipped with The pair of non-contact areas of the heat generating element are fixed to the heat sink via sheet materials. A heat dissipation structure characterized by:

4. The heat dissipation structure according to claim 3, The pair of non-contact areas of the heating element are sandwiched between a pair of sheet materials. A heat dissipation structure characterized by:

5. The heat dissipation structure according to claim 1 , A substrate and a semiconductor chip mounted on the substrate, the semiconductor chip comprises a substrate and a die; The electrical component is the die. A heat dissipation structure characterized by:

6. An electronic device having a heat-generating electrical component, a metal mesh abutting a surface of the electrical component; a heat sink that holds the metal mesh between the heat sink and a surface of the electrical component; having The metal mesh is The metal mesh is impregnated with a heat conductive fluid at least in the portion that contacts the surface of the electrical component, and the intersections of the vertical and horizontal wires are crushed in the thickness direction.

1. An electronic device comprising:

7. A method for manufacturing an electronic device having a heat-generating electrical component, comprising the steps of: pressing the metal mesh; impregnating the metal mesh with a thermally conductive fluid; sandwiching the metal mesh between a surface of the electrical component and a heat sink; have 2. A method for manufacturing an electronic device comprising the steps of:

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