Electronic equipment, vapor chamber and preparation method of vapor chamber

Abstract

The invention discloses electronic equipment, a vapor chamber and a preparation method thereof, and relates to the field of electronic equipment. The heat dissipation performance of the vapor chamber is improved. According to the specific scheme, the vapor chamber comprises a first metal layer, a second metal layer and a capillary structure, wherein the first metal layer comprises a first main body part and a first edge part; the second metal layer comprises a second main body part and a second edge part; the surfaces of the first edge part and the second edge part are connected to form a connecting layer, and the number of grains with the grain size smaller than or equal to 50 microns in the connecting layer accounts for 70% or above. The crystal grains of the connecting layer are small, impurities influencing the capillary force of the capillary structure in the containing cavity can be prevented from entering the containing cavity, and the heat dissipation performance of the vapor chamber is good. The vapor chamber can comprise a metal cover plate and a connecting layer, is mainly composed of metal grains with relatively small grain sizes, and can have the characteristics of high strength and high rigidity macroscopically. Part of non-metal materials can also be included, the high-flexibility characteristic is achieved, and the heat dissipation characteristic requirements of different electronic products are met.

Description

Electronic equipment, temperature distribution board and preparation method thereof

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on January 2, 2024, with application number 202410009564.5 and application name “Electronic device, temperature spreader and preparation method thereof”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of electronic devices, and in particular to an electronic device, a temperature vapor chamber, and a method for manufacturing the same. Background Art

[0003] Electronic devices (such as mobile phones) generate heat when working. If this heat accumulates inside the electronic device for a long time, it will cause the temperature of the electronic product to rise, affecting the user experience and even causing failures. Currently, vapor chambers (VCs) are used to dissipate heat on electronic devices. A vapor chamber is a vacuum cavity with a capillary structure on the inner wall and a working medium (i.e., a working medium). At present, the heat dissipation performance of the vapor chamber has become an important factor affecting the heat dissipation performance of electronic devices. Therefore, improving the heat dissipation performance of the vapor chamber is an urgent problem that needs to be solved by the vapor chamber.

[0004] Summary of the Invention

[0005] The embodiments of the present application provide an electronic device, a temperature vapor chamber, and a method for manufacturing the same, aiming to improve the heat dissipation performance of the temperature vapor chamber.

[0006] In order to achieve the above objectives, this application adopts the following technical solutions.

[0007] In a first aspect, embodiments of the present application provide a temperature-vaporizing plate. The temperature-vaporizing plate includes a first cover plate, a second cover plate, and a capillary structure. The first cover plate includes a first metal layer, the first metal layer including a first main body and a first edge portion surrounding the outer periphery of the first main body. The second cover plate includes a second metal layer, the second metal layer including a second main body and a second edge portion surrounding the outer periphery of the second main body. The surface of the first edge portion and the surface of the second edge portion are connected to form a connecting layer, and the first and second main bodies together form a receiving cavity. The capillary structure is located within the receiving cavity and connected to the first main body. In a direction perpendicular to the thickness of the connecting layer, at least 5 mm of the connecting layer has a grain size of less than or equal to 50 μm, accounting for 70% or more of the total grain count. As a result, the connection between the first and second cover plates has the advantage of small grain size, which facilitates uniform stress between the first and second edge portions, and provides excellent mechanical properties between the first and second edge portions. In addition, the smaller grain size of the first edge portion can prevent other grain structures on the side of the first metal layer facing away from the storage cavity from passing through the first edge portion and entering the storage cavity, thereby preventing the aforementioned other grain structures from affecting the capillary force of the capillary structure within the storage cavity and reducing the heat dissipation performance of the heat spreader. Similarly, the smaller grain size of the second edge portion can prevent other grain structures on the side of the second metal layer facing away from the storage cavity from affecting the capillary force of the capillary structure within the storage cavity. The better the capillary force of the capillary structure, the better the heat dissipation performance of the heat spreader, which can effectively improve the heat dissipation performance of the heat spreader.

[0008] In conjunction with the first aspect, in some achievable embodiments, the number of grains with a grain size of less than or equal to 50 μm in the connection layer accounts for 70% or more of the total number of grains. Thus, the entire connection between the first cover plate and the second cover plate has the advantage of excellent mechanical properties.

[0009] In conjunction with the first aspect, in some achievable embodiments, the number of grains with a grain size of less than or equal to 50 μm in the connection layer accounts for 90% or more of the total number of grains. Thus, the entire connection between the first cover plate and the second cover plate has the advantage of excellent mechanical properties.

[0010] In combination with the first aspect, in some feasible methods, the material of the first metal layer is a first metal material, the first edge portion has a first surface and a second surface arranged opposite to each other, the second surface is connected to the surface of the second edge portion, and the mass percentage of the first metal material is greater than or equal to 95% at a distance greater than or equal to 3μm from the first surface in the first edge portion. As a result, the first edge portion is mainly made of the first metal material, and there is little or almost no other material other than the first metal material, thereby avoiding that other materials other than the first metal material have a greater impact on the connection performance between the first edge portion and the second edge portion. This improves the problem of reduced heat dissipation performance of the heat spreader due to the reaction of other materials other than the first metal material with the working fluid.

[0011] In conjunction with the first aspect, in some achievable embodiments, the second metal layer is made of a second metal material, the second edge portion has a third surface and a fourth surface disposed opposite each other, the fourth surface being connected to the surface of the first edge portion, and the mass percentage of the second metal material within the second edge portion at a distance of 3 μm or greater from the third surface is greater than or equal to 95%. This improves the mechanical properties of the second edge portion and can alleviate the problem of reduced heat dissipation performance of the vapor chamber caused by the presence of a large amount of material other than the second metal material.

[0012] In conjunction with the first aspect, in some achievable embodiments, the first cover plate further includes a support layer connected to a side of the first metal layer remote from the second metal layer. Thus, provision of the support layer can increase the thickness of the first cover plate. The strength and thickness of the first cover plate can be adjusted by adjusting the mechanical strength and thickness of the support layer.

[0013] In conjunction with the first aspect, in some achievable embodiments, the second cover plate further includes a support layer connected to a side of the second metal layer away from the first metal layer. Thus, provision of the support layer can improve the strength of the second cover plate.

[0014] In conjunction with the first aspect, in some achievable embodiments, the material of the support layer includes at least one of titanium and its alloys, aluminum and its alloys, magnesium and its alloys, and steel. This provides a wider range of material options for the support layer. Furthermore, because the number of grains with a grain size of less than or equal to 50 μm in the connecting layer, which is at least 5 mm long, accounts for 70% or more of the total grain count, the material of the support layer is unlikely to penetrate the first metal layer and enter the accommodation cavity. Consequently, the material choice of the support layer has a minimal impact on the heat dissipation performance of the working medium within the accommodation cavity.

[0015] In conjunction with the first aspect, in some achievable embodiments, the first cover plate further includes a polymer layer connected to a side of the first metal layer remote from the second metal layer. The polymer material has a low density, which helps reduce the mass of the first cover plate, making the vapor chamber lightweight and flexible.

[0016] In conjunction with the first aspect, in some achievable embodiments, the second cover plate further comprises a polymer layer connected to a side of the second metal layer away from the first metal layer. The polymer material has a low density, which helps reduce the mass of the second cover plate and make the vapor chamber lighter.

[0017] In combination with the first aspect, in some achievable embodiments, the material of the first metal layer includes at least one of copper and its alloys, and aluminum and its alloys.

[0018] In conjunction with the first aspect, in some achievable embodiments, the thickness of the first metal layer is 5μm-80μm. This is because the number of grains with a grain size of less than or equal to 50μm in the connection layer, which is at least 5mm long, accounts for 70% or more of the total number of grains. Even if the thickness of the first metal layer is only 5μm, the connection performance at the junction of the first edge portion and the second edge portion is excellent, and the first metal layer can effectively isolate substances that generate non-condensable gases from entering the accommodation cavity, thus ensuring that the vapor chamber has excellent heat dissipation performance.

[0019] In conjunction with the first aspect, in some achievable embodiments, the thickness of the first metal layer can be 5 μm-10 μm. A smaller thickness of the first metal layer can save on the amount of the first metal layer used. Furthermore, within this range, the first metal layer can still reduce the amount of impurities that enter the containment cavity and reduce the generation of non-condensable gases within the containment cavity.

[0020] In combination with the first aspect, in some feasible embodiments, the heat spreader further includes: a plurality of protrusions spaced apart in the accommodating cavity, one end of each of the plurality of protrusions being connected to the second main body, and the other end being a free end. Thus, the plurality of protrusions can increase the surface area in the accommodating cavity, increase the contact area between the working fluid and the accommodating cavity, and make it easier for the working fluid to adhere to the accommodating cavity. Secondly, the plurality of protrusions can guide the gaseous working fluid. In addition, the protrusions also have the function of drainage, and the working fluid attached to the surface of the protrusions can flow and converge along the surface of the protrusions, which is beneficial to shorten the time of the thermal cycle of the working fluid and increase the heat dissipation performance of the heat spreader.

[0021] In conjunction with the first aspect, in some achievable embodiments, the capillary structure is connected to the first main body as an integrally formed component. This provides excellent connectivity between the capillary structure and the first main body, making them difficult to separate. In scenarios where the heat spreader bends, the integrally formed first main body and capillary structure can effectively reduce friction caused by the relative movement between the capillary structure and the first main body during bending. Furthermore, if the first main body bends, delamination and tearing between the capillary structure and the first main body are less likely to occur.

[0022] In a second aspect, embodiments of the present application provide a method for manufacturing a heat spreader. The method comprises: providing a first cover plate, a second cover plate, and a capillary structure. The first cover plate comprises a first metal layer, the first metal layer comprising a first main body and a first edge portion surrounding the first main body; the second cover plate comprises a second metal layer, the second metal layer comprising a second main body and a second edge portion surrounding the second main body; and the capillary structure is connected to the first main body. A first heat treatment is performed on the first cover plate, the capillary structure, and the second cover plate, which are stacked in sequence, to connect the first edge portion and the second edge portion. The first heat treatment temperature is 150°C to 400°C, the pressure is greater than or equal to 30 MPa, and the duration is greater than or equal to 30 minutes. Due to the low temperature of the first heat treatment, the problem of deformation and oxidation of the first and second cover plates caused by high temperatures is effectively alleviated. In addition, due to the low temperature, the first heat treatment process has a relatively low impact on the hardness and yield strength of the first and second cover plates. The first metal layer and the second metal layer have relatively small grains at 150°C-400°C, so that more than 70% of the grains in the connecting layer are less than 50μm in size. The grains in the connecting layer are uniform and small, the internal stress of the connecting layer is low, and it is not easy to delaminate or crack.

[0023] In combination with the second aspect, in some achievable embodiments, the pressure of the first heat treatment is 30 MPa-200 MPa, and the time is 30 min-100 min.

[0024] In combination with the second aspect, in some feasible methods, before the first heat treatment step is performed on the first cover plate, the capillary structure and the second cover plate stacked in sequence, the step further includes: performing a second heat treatment on the first cover plate and the capillary structure to connect the capillary structure to the first main body. The temperature of the second heat treatment is 150°C-400°C, the pressure is greater than or equal to 5MPa, and the time is greater than or equal to 30min. Since the temperature of the second heat treatment is relatively low, the second heat treatment process has little effect on the capillary structure and the first cover plate, so that the first cover plate can maintain good hardness and yield strength after the second heat treatment. During the second heat treatment, the amount of grain growth in the first cover plate is small, and the elements on the side of the first cover plate away from the capillary structure are not easy to diffuse to the side close to the capillary structure. During the second heat treatment of the capillary structure, the micro-nano structure on the capillary structure is not easy to collapse or deform, and can still maintain good capillary force.

[0025] In combination with the second aspect, in some achievable embodiments, the pressure is 5 MPa-200 MPa, and the time is 30 min-100 min.

[0026] In conjunction with the second aspect, in some achievable embodiments, before the first heat treatment step is performed on the first cover plate, the capillary structure, and the second cover plate stacked in sequence, the step further includes: stacking the first cover plate, the capillary structure, and the second cover plate, and filling nanoparticles between the first edge portion and the second edge portion. Thus, the nanoparticles help the grains on the surfaces of the first edge portion and the second edge portion to quickly fuse during the first treatment process. The nanoparticles act as crystal nuclei of the grains, helping to shorten the nucleation time on the surfaces of the first edge portion and the second edge portion, and shortening the formation time of the connecting layer.

[0027] In a third aspect, embodiments of the present application provide an electronic device. The electronic device includes a printed circuit board and any of the heat spreaders provided in the first aspect, wherein the first cover is connected to the printed circuit board. Because the heat spreader has excellent heat dissipation performance, the heat spreader can cool the printed circuit board, thereby improving the heat dissipation performance of the electronic device.

[0028] In conjunction with the third aspect, in some achievable embodiments, the electronic device further comprises: a middle frame; the temperature vapor chamber, the middle frame, and the printed circuit board are stacked in sequence; the middle frame is provided with a through hole extending through the middle frame along the thickness direction of the middle frame, and the first cover plate is connected to the printed circuit board through the through hole. This is conducive to reducing the total thickness of the middle frame and the temperature vapor chamber, improving the integration of the electronic device, and facilitating the miniaturization of the electronic device. In addition, the temperature vapor chamber can be regarded as part of the middle frame, providing support strength for structures such as the display screen, so that the temperature vapor chamber can take on multiple functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1a is a schematic structural diagram of an electronic device.

[0030] FIG1 b is a schematic diagram of the structure of the middle frame and the temperature vapor chamber provided in an embodiment of the present application.

[0031] FIG2 a is a schematic diagram of the structure of a temperature homogenizing plate provided in an embodiment of the present application.

[0032] FIG2 b is a schematic diagram of the exploded structure of the temperature homogenizing plate provided in an embodiment of the present application.

[0033] FIG3 a is a schematic structural diagram of a vapor chamber in the related art.

[0034] FIG3 b is a schematic cross-sectional view of a vapor chamber obtained by a process at section CC in FIG3 a .

[0035] FIG3 c is a schematic cross-sectional view of a vapor chamber obtained by another process at section CC in FIG3 a .

[0036] FIG3 d is a schematic cross-sectional view of a vapor chamber obtained by another process at section CC in FIG3 a .

[0037] FIG4 a is a schematic cross-sectional view of the first edge portion and the second edge portion, with the example being 50 μm.

[0038] FIG4 b is a schematic cross-sectional view of the first edge portion and the second edge portion, with the example being 20 μm.

[0039] FIG4 c is a schematic cross-sectional view of the first edge portion and the second edge portion, with the example being 1 μm.

[0040] FIG5a is a schematic cross-sectional view of a portion DD in FIG2a.

[0041] FIG5 b is another cross-sectional schematic diagram of the portion DD in FIG2 a .

[0042] FIG5c is another cross-sectional schematic diagram of the portion DD in FIG2a.

[0043] FIG5 d is another cross-sectional schematic diagram of a portion DD in FIG2 a .

[0044] FIG6 a is a schematic diagram of the internal structure of another temperature vapor chamber provided in an embodiment of the present application.

[0045] FIG6 b is a schematic diagram of the internal structure of another temperature homogenizing plate provided in an embodiment of the present application.

[0046] FIG7 a is a process flow chart of a temperature vapor chamber provided in an embodiment of the present application.

[0047] FIG7 b is a schematic structural diagram when step s2 in FIG7 a is executed.

[0048] FIG7c is a schematic structural diagram when s3 in FIG7a is executed.

[0049] FIG7 d is a schematic structural diagram when s4 in FIG7 a is executed.

[0050] In the figure: 10-electronic device; 11-cover plate; 12-display screen; 13-printed circuit board; 14-middle frame; 15-back shell; 16-frame; 17-through hole; 171-stepped surface; 100-heat spreader; 110-first cover plate; 120-second cover plate; 130-capillary structure; 111-first metal layer; 101-first main body; 102-first edge portion; 112-support layer; 113-polymer layer; 121-second metal layer; 201-second main body; 202-second edge portion; 20-connecting layer; 140-accommodating cavity; 150-protrusion; 01-heat spreader; 02-upper cover; 03-lower cover; 04-capillary element; 05-solder layer; 06-guide column; 103-first surface; 104-second surface; 122-opening; 203-third surface; 204-fourth surface. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of this application clearer, this application will be further described in detail below with reference to the accompanying drawings.

[0052] Hereinafter, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified with "first," "second," etc., may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0053] In addition, in this application, directional terms such as "upper" and "lower" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to changes in the orientation of the components in the drawings.

[0054] Vapor chamber (VC): Also known as a heat spreader, it is a vacuum cavity with a microstructure on the inner wall and capable of injecting a working fluid. The working principle of the vapor chamber specifically includes four main steps: conduction, evaporation, convection, and condensation. When the heat generated by the heat source enters the vapor chamber through heat conduction, the working fluid near the heat source in the vapor chamber will quickly vaporize after absorbing the heat, taking away a large amount of heat at the same time. Reusing the heat dissipation properties of steam, when the steam in the vapor chamber diffuses from the high-temperature zone to the low-temperature zone, when the steam contacts the inner wall with a lower temperature, it will quickly condense into liquid and release heat energy; the working fluid condensed into liquid returns to the heat source through the capillary structure, thereby completing a heat conduction cycle and forming a two-way circulation system in which the working fluid coexists in both vapor and liquid phases.

[0055] Capillary structure: Due to surface tension, when a liquid is immersed in a capillary pore, its surface is concave. This surface exerts a pulling force on the liquid below, causing it to move upward along the pore wall. This triggers the capillary phenomenon. The capillary structure can include multiple capillaries or microscopic grooves similar to capillaries. Once the liquid enters the capillary pores or microscopic grooves in the capillary structure, it flows to the other end of the pore through capillary action, completing the transfer and return of the liquid.

[0056] The present application provides an electronic device, which may be a terminal device having an antenna and an electrical connector. The electronic device may be implemented in various forms, including but not limited to a mobile phone, a tablet computer, a personal digital assistant (PDA), a desktop computer, a wearable device, a display device (such as a television), an information display device, or a smart home terminal. In addition, in an embodiment of the present application, the electronic device may be a foldable device, such as a foldable mobile phone. The electronic device may also be a bar phone. In the embodiment of the present application, the electronic device is exemplified as a mobile phone.

[0057] Figure 1a is a schematic diagram of the structure of an electronic device 10. As shown in Figure 1a, electronic device 10 may include a cover 11, a display 12, a printed circuit board (PCB) 13, a middle frame 14, and a rear housing 15. In some embodiments, rear housing 15 is also called a rear cover. Cover 11, display 12, and rear housing 15 are stacked.

[0058] The cover plate 11 can be placed closely against the display screen 12 to protect and prevent dust from forming on the display screen 12. The cover plate 11 can be made of glass or other materials, such as ultra-thin glass or PET.

[0059] The display screen 12 may include a liquid crystal display (LCD), a light emitting diode (LED), or an organic light emitting diode (OLED) display panel, etc., and this application does not limit this. The types of the display screen 12 include, but are not limited to, a water drop screen, a notch screen, a full screen, or a punch-hole screen.

[0060] The middle frame 14 supports the entire device. Made of a highly thermally conductive material (e.g., copper or aluminum), the middle frame 14 has a high thermal conductivity, allowing it to dissipate heat from within the electronic device 10 to the exterior. The printed circuit board 13 shown in FIG1a is positioned between the middle frame 14 and the rear housing 15. It should be understood that in some embodiments, the printed circuit board 13 may also be positioned between the middle frame 14 and the display screen 12, although this is not a limitation in the present application.

[0061] For example, the electronic device 10 may further include a battery (not shown). The battery may be disposed between the middle frame 14 and the rear housing 15, or between the middle frame 14 and the display screen 12, which is not limited in this application.

[0062] For example, the printed circuit board 13 carries electronic components, such as a radio frequency chip. In some embodiments, components such as input buttons, a transmitter, a processor, a memory, a battery, a charging circuit, and a system on chip (SoC) structure can be mounted on or connected to the printed circuit board 13.

[0063] In some embodiments, the printed circuit board 13 is divided into a main board and a sub-board, and the battery can be arranged between the main board and the sub-board, wherein the main board can be arranged between the middle frame 14 and the upper edge of the battery, and the sub-board can be arranged between the middle frame 14 and the lower edge of the battery.

[0064] In some embodiments, electronic device 10 may further include a frame 16, which may be formed of a conductive material such as metal. Frame 16 may be disposed between display screen 12 and rear housing 15 and extend circumferentially around display screen 12. Frame 16 may have four sides surrounding display screen 12, and the four sides may help secure display screen 12.

[0065] In Figure 1a, the frame 16 and the middle frame 14 are connected as an integral part, and together they support the entire electronic device 10. The rear housing 15 and the cover 11 are respectively attached along opposite sides of the frame 16 to form the outer shell or housing of the electronic device. In other embodiments, the frame 16 and the middle frame 14 may be connected by means of spring clips, screws, welding, or the like.

[0066] In some embodiments, electronic device 10 includes a vapor chamber 100 , which can be connected to electronic components carried on a printed circuit board 13 . When electronic device 10 is operating, printed circuit board 13 generates a significant amount of heat, and vapor chamber 100 , connected to printed circuit board 13 , can dissipate heat from printed circuit board 13 .

[0067] The embodiment of the present application does not limit the connection method between the temperature plate 100 and the printed circuit board 13. In some embodiments, the middle frame 14 is located between the printed circuit board 13 and the temperature plate 100. The heat on the printed circuit board 13 is transferred to the middle frame 14 and then dissipated by the temperature plate 100. In some embodiments, a hollow area is provided on the middle frame 14, and some devices (such as chips) of the printed circuit board 13 pass through the aforementioned hollow area to fit the temperature plate 100. Alternatively, part of the temperature plate 100 passes through the aforementioned hollow area to fit the printed circuit board 13.

[0068] In some embodiments, the temperature vapor chamber 100 may be located between the middle frame 14 and the printed circuit board 13 .

[0069] It is understandable that in other embodiments of the present application, the temperature vapor chamber 100 can be connected to other structures in the electronic device 10 (such as the rear housing 15, etc.), and the embodiments of the present application do not limit this.

[0070] FIG2 a is a schematic structural diagram of a heat spreader 100 according to an embodiment of the present invention. Referring to FIG2 a , the heat spreader 100 includes a first cover plate 110 and a second cover plate 120 , which together enclose a receiving cavity 140 .

[0071] Figure 2b is a schematic diagram of the exploded structure of the heat spreader 100 provided in an embodiment of the present application. Referring to Figure 2b, the heat spreader 100 further includes a capillary structure 130. The first cover plate 110, the capillary structure 130, and the second cover plate 120 are stacked in this order. The thickness direction of the heat spreader 100 is defined as the z-direction, and the first cover plate 110, the capillary structure 130, and the second cover plate 120 are stacked along this z-direction.

[0072] The first cover plate 110 includes a first metal layer 111, which includes a first main portion 101 and a first edge portion 102. The first edge portion 102 is disposed around the periphery of the first main portion 101 and is connected to the first main portion 101, for example, the first edge portion 102 and the first main portion 101 are connected to each other as a single piece. The second cover plate 120 includes a second metal layer 121, which includes a second main portion 201 and a second edge portion 202. The second edge portion 202 is disposed around the periphery of the second main portion 201 and is connected to the second edge portion 202, for example, the second main portion 201 and the second edge portion 202 are connected to each other as a single piece.

[0073] The first metal layer 111 and the second metal layer 121 are stacked along the z-direction. The surface of the first edge portion 102 and the surface of the second edge portion 202 are connected to form a connection layer 20. Specifically, the connection layer 20 includes the connected first edge portion 102 and the second edge portion 202. The first main portion 101 and the second main portion 201 together enclose a receiving cavity 140. The capillary structure 130 is located within the receiving cavity 140 and connected to the first main portion 101. In the connection layer 20, which is at least 5 mm long, the number of grains having a grain size of less than or equal to 50 μm (micrometers) accounts for 70% or more of the total number of grains.

[0074] In the embodiments of the present application, the "edge" of the first edge portion 102 refers to the portion located at the periphery of the first main body portion 101 and directly connected to or in direct contact with the first main body portion 101. Similarly, the "edge" of the second edge portion 202 refers to the portion located at the periphery of the second main body portion 201 and directly connected to or in direct contact with the second main body portion 201. There are no bubbles between the first edge portion 102 and the second edge portion 202, or the size of the bubbles between the first edge portion 102 and the second edge portion 202 is less than or equal to 10μm. The embodiments of the present application do not limit the widths of the first edge portion 102 and the second edge portion 202.

[0075] Figure 3a is a schematic diagram of the structure of a vapor chamber 01 in the related art. In Figure 3a, vapor chamber 01 comprises an upper cover 02, a lower cover 03, a guide column 06, and a capillary element 04. The upper and lower covers 02 and 03 together form a cavity, within which both the capillary element 04 and the guide column 06 are located. Both the upper and lower covers 02 and 03 are made of copper.

[0076] FIG3b is a schematic cross-sectional view of a heat spreader 01 obtained by a process at section CC in FIG3a. In FIG3b, the upper cover 02 and the lower cover 03 are connected by high-temperature diffusion welding. The welding temperature is in the range of 700°C-850°C. The temperature of 700°C-850°C will reduce the capillary force of the capillary element and cause deformation of the upper cover 02 and the lower cover 03, resulting in low structural strength of the heat spreader 01. The legend of FIG3b (1) is 50μm, and the legend of FIG3b (2) is 20μm. As can be seen from FIG3b, the grain size at the connection between the upper cover 02 and the lower cover 03 is 29μm-140μm. The grains are coarse.

[0077] FIG3c is a schematic cross-sectional view of the heat spreader 01 obtained by another process at section CC in FIG3a. In FIG3c, the upper cover 02 and the lower cover 03 are welded by solder paste, and a solder layer 05 is formed between the upper cover 02 and the lower cover 03. The legend of FIG3c (1) is 20 μm, and the legend of FIG3c (2) is 50 μm. As can be seen from FIG3c, there are pores at the connection between the upper cover 02 and the lower cover 03. The presence of pores will affect the airtightness and vacuum degree of the heat spreader 01, resulting in a decrease in the heat dissipation performance of the heat spreader 01. In addition, the grain size at the connection between the upper cover 02 and the lower cover 03 is 91 μm-102 μm. The grains are coarse. In addition, during the welding process of the upper cover 02 and the lower cover 03, the solder paste enters the cavity and affects the capillary force of the capillary element. The solder paste will decompose at high temperature to generate non-condensable gases (NCG), which will affect the vacuum degree of the cavity and reduce the heat dissipation performance of the heat spreader 01. The solder paste will form a solder layer between the upper cover 02 and the lower cover 03 , and the solder layer will reduce the mechanical strength and yield strength of the heat spreader 01 .

[0078] FIG3d is a schematic cross-sectional view of the heat spreader 01 obtained by another process at section CC in FIG3a. The upper cover 02 in FIG3d includes a copper layer and a stainless steel layer stacked together. The lower cover 03 includes a copper layer and a stainless steel layer stacked together. The legend of FIG3d (1) is 3 μm, and the legend of FIG3d (2) is 10 μm. The dark gray in the dotted box in FIG3d (1) is stainless steel, and the light gray is copper grains. As can be seen in FIG3d, the copper grains at the connection between the upper cover 02 and the lower cover 03 are relatively large, and some components of the stainless steel (such as carbon and iron) are doped between the copper grains. The components of the aforementioned stainless steel (such as iron grains) enter the cavity and generate non-condensable gas with the water in the cavity, affecting the vacuum degree of the cavity and reducing the heat dissipation of the heat spreader 01.

[0079] Furthermore, in related technologies, during the connection process between the upper and lower covers, the grains within each grow, with some reaching sizes as high as 100μm. This grain growth reduces the strength of the upper and lower covers. After connection, the hardness and yield strength of the upper and lower covers decrease by as much as 40%, severely impacting the mechanical properties of the vapor chamber.

[0080] The heat dissipation capability of the heat vapor chamber 100 provided in the embodiment of the present application is better.

[0081] Please return to Figure 2b. In this application, the number of grains with a grain size of less than or equal to 50μm in the connecting layer 20 that is at least 5mm long accounts for 70% or more of the total number of grains. The length of the connecting layer 20 mentioned above refers to the dimension of the connecting layer 20 along the direction perpendicular to the thickness direction of the connecting layer 20. That is, along the direction perpendicular to the z-direction, the number of grains with a grain size of less than or equal to 50μm in the connecting layer 20 that is at least 5mm long accounts for 70% or more of the total number of grains. Because there are multiple directions perpendicular to the z-direction, it is sufficient that the number of grains with a grain size of less than or equal to 50μm in the connecting layer 20 that is at least 5mm long in any one direction accounts for 70% or more of the total number of grains. Exemplarily, the number of grains having a grain size less than or equal to 50 μm in the aforementioned connecting layer 20 having a length of at least 5 mm accounts for 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% of the total number of grains.

[0082] Here, a crystal grain refers to a tiny or micron-sized crystal. The aforementioned grain size is the linear length of the grain, or the diameter of the grain, which refers to the largest dimension of the grain in all directions. For example, the grain size can be obtained by obtaining a crystal phase diagram using X-ray diffraction patterns, metallography, scanning electron microscope (SEM), etc.

[0083] The connection between the first cover plate 110 and the second cover plate 120 has the advantage of a small grain size. Small grains facilitate uniform stress between the first edge portion 102 and the second edge portion 202, and provide excellent mechanical properties between the first edge portion 102 and the second edge portion 202. Furthermore, the smaller grain size of the first edge portion 102 prevents other grain structures on the side of the first metal layer 111 facing away from the accommodating cavity 140 from passing through the first edge portion 102 and entering the accommodating cavity 140, thereby preventing these other grain structures from affecting the capillary force of the capillary structure 130 within the accommodating cavity 140 and reducing the heat dissipation performance of the vapor chamber 100. Similarly, the smaller grain size of the second edge portion 202 prevents other grain structures on the side of the second metal layer 121 facing away from the accommodating cavity 140 from affecting the capillary force of the capillary structure 130 within the accommodating cavity 140. The better the capillary force of the capillary structure 130, the better the heat dissipation performance of the vapor chamber 100, effectively improving the heat dissipation performance of the vapor chamber 100.

[0084] In addition, the small grain size in the first edge portion 102 and the second edge portion 202 indicates that during the process of connecting the first edge portion 102 and the second edge portion 202, the internal grain growth of the first edge portion 102 and the second edge portion 202 is small. This indicates that the process conditions for connecting the first edge portion 102 and the second edge portion 202 may not contain process conditions that cause large grain growth (such as high temperature), thereby avoiding such process conditions from weakening the mechanical properties of the first cover plate 110 and the second cover plate 120 and reducing the capillary force of the capillary structure 130. For example, high temperature can cause the micro-nano structure on the surface of the capillary structure 130 to collapse or melt. The aforementioned micro-nano structure includes micron- or nano-scale pores, barb structures, or needle-like protrusions on the surface of the capillary structure 130.

[0085] In some embodiments, the number of grains in the connection layer 20 with a grain size of 50 μm or less accounts for 70% or more of the total number of grains. In other words, more than 70% of the grains in the entire connection layer 20 have a size of 50 μm or less. This allows the entire connection between the first cover plate 110 and the second cover plate 120 to have excellent mechanical properties, and the vapor chamber 100 has better heat dissipation performance.

[0086] In the embodiment of the present application, the “metal” in the first metal layer 111 is not limited to a single metal, but may include a metal alloy. The same applies to the “metal” in the second metal layer 121 .

[0087] Exemplarily, the material of the first metal layer 111 includes at least one of copper and its alloys, and aluminum and its alloys. Copper and its alloys, and aluminum and its alloys have relatively low melting points, and the temperature requirement for the connection process between the first metal layer 111 and the second metal layer 121 is relatively low (e.g., 150°C-400°C). It is understood that the first metal layer 111 may also include unavoidable impurities, such as impurities that are unavoidable during the process of forming the raw materials of the first metal layer 111 at the current level of technology.

[0088] Similarly, in some embodiments, the material of the second metal layer 121 includes at least one of copper and its alloys, or aluminum and its alloys. The following description uses copper as an example. In embodiments where both the first metal layer 111 and the second metal layer 121 are made of copper, copper has excellent ductility. When copper is connected to copper, the connection between the first edge portion 102 and the second edge portion 202 is more tightly connected. Furthermore, copper's excellent heat transfer properties can improve the thermal conductivity of the vapor chamber 100.

[0089] Figure 4a is a schematic cross-sectional view of the first edge portion 102 and the second edge portion 202 at a depth of 50 μm. As can be seen from Figure 4a , the crystal structures of the first edge portion 102 and the second edge portion 202 are uniform, and there are almost no bubbles or gaps at the joint between the first edge portion 102 and the second edge portion 202 (the dotted line in Figure 4a ).

[0090] Figure 4b is a schematic cross-sectional view of the first edge portion 102 and the second edge portion 202, with a cross-sectional view of 20 μm. The maximum grain size in the cross-sectional view of Figure 4b is 19 μm. Figure 4c is a schematic cross-sectional view of the first edge portion 102 and the second edge portion 202, with a cross-sectional view of 1 μm. The maximum grain size in the cross-sectional view of Figure 4c is 4 μm. Furthermore, there is no gap between the first edge portion 102 and the second edge portion 202, indicating that the joint between the first edge portion 102 and the second edge portion 202 is airtight.

[0091] In some embodiments, grains with a grain size of 50 μm or less account for 70% or more of the total grains in the first main body 101. For example, grains with a grain size of 50 μm or less account for 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% of the total grains in the first main body 101. Thus, the first main body 101 also has excellent mechanical properties. Similarly, in some embodiments, grains with a grain size of 50 μm or less account for 70% or more of the total grains in the second main body 201. Thus, the second main body 201 also has excellent mechanical properties.

[0092] In some embodiments, the pore size between the first edge portion 102 and the second edge portion 202 is less than or equal to 2 μm. For example, the pore size between the first edge portion 102 and the second edge portion 202 is 0 μm, 0.001 μm, 0.1 μm, 0.2 μm, 0.3 μm, 0.5 μm, 0.8 μm, 1 μm, 1.1 μm, 1.2 μm, 1.5 μm, 1.8 μm, or 2 μm. There are no pores or the pores are relatively small between the first edge portion 102 and the second edge portion 202, thereby achieving excellent airtightness between the first edge portion 102 and the second edge portion 202. Furthermore, problems such as uneven stress and low structural strength between the first edge portion 102 and the second edge portion 202 caused by pores can be avoided.

[0093] Please return to Figure 4a. In the example of Figure 4a, the material other than the material of the first metal layer 111 in the first edge portion 102 accounts for a small proportion. Exemplarily, the material of the first metal layer 111 includes a first metal material. The first edge portion 102 includes a first surface 103 and a second surface 104 arranged opposite to each other, and the second surface 104 is connected to the surface of the second edge portion 202. The first surface 103 is a surface facing away from the second edge portion 202. At a distance greater than or equal to 3μm from the first surface 103 in the first edge portion 102, the mass percentage of the first metal material is greater than or equal to 95%. In Figure 4a, region G1 is located in the first edge portion 102, and the distance between each point in region G1 and the first surface 103 is greater than or equal to 3μm. The mass percentage of the first metal material in region G1 is greater than or equal to 95%. For example, the mass percentage of the first metal material in region G1 is 95%, 96%, 97%, 98%, 99.0%, 99.2%, 99.5%, 99.8%, 99.9%, 99.99%, or 100%. In this way, the first edge portion 102 is primarily composed of the first metal material, with little or no other material other than the first metal material. This prevents the other material from significantly affecting the connection between the first edge portion 102 and the second edge portion 202. This improves the problem of reduced heat dissipation performance of the vapor chamber due to the reaction of other materials other than the first metal material with the working fluid.

[0094] In the embodiment where the first metal layer 111 is a copper layer, the first metal material is copper. Within the aforementioned region G1, 70% of the copper grains have a size of less than or equal to 50 μm, and the mass percentage of copper within region G1 is greater than or equal to 95%. In other words, within region G1, the copper grains are fine and uniform, and the content of non-copper materials is low. This non-copper material has a minimal impact on the brittleness of region G1, resulting in better mechanical properties within region G1.

[0095] By analogy, in an embodiment where the first metal layer 111 is a copper alloy layer, the first metal material is a copper alloy. The mass percentage of the copper alloy in the region G1 is greater than or equal to 95%. In an embodiment where the first metal layer 111 is an aluminum alloy layer, the first metal material is an aluminum alloy. The mass percentage of the aluminum alloy in the region G1 is greater than or equal to 95%.

[0096] Similarly, the material of the second edge portion 202 includes a second metal material. The second edge portion 202 includes a third surface 203 and a fourth surface 204 disposed opposite each other, with the fourth surface 204 being connected to the surface of the first edge portion 102. The third surface 203 is the surface facing away from the first edge portion 102. Within the second edge portion 202, at a distance greater than or equal to 3 μm from the third surface 203, the mass percentage of the second metal material is greater than or equal to 95%. In Figure 4a, region G2 is located within the second edge portion 202, and the distance between each point within the region and the third surface 203 is greater than or equal to 3 μm. The mass percentage of the second metal material within region G2 is 95%, 96%, 97%, 98%, 99.0%, 99.2%, 99.5%, 99.8%, 99.9%, 99.99%, or 100%, etc. Similar to the aforementioned first edge portion 102 , the mechanical properties in the region G2 are better, and the problem of reduced heat dissipation performance of the vapor chamber due to the presence of more materials other than the second metal material can be alleviated.

[0097] In some embodiments, within the connection layer 20, at a distance greater than or equal to 3 μm from the third surface 203 and greater than or equal to 3 μm from the first surface 103, the mass percentage of the doping material is less than or equal to 5%. For example, the mass percentage of the doping material is 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.01%, or 0. The doping material is a material other than the second metal material and the first metal material. Thus, solder and the like are not included in the connection layer 20, thereby avoiding the non-condensable gas problem caused by solder, as shown in FIG. 3c .

[0098] In other embodiments, a trace amount of dopant material may be present at the junction of the second surface 104 and the fourth surface 204. The mass percentage of the dopant material is less than or equal to 10%, for example, 10%, 8%, 7%, 5%, 4%, 2%, 1%, 0.5%, 0.1%, or 0.01%. The dopant material may be carbon. The dopant material can be considered as a crystal nucleus of the first metal material.

[0099] Exemplarily, a first groove 1221 is provided on the side of the first edge portion 102 facing the second edge portion 202, and a second groove 1222 is provided on the side of the second edge portion 202 facing the first edge portion 102. After the first edge portion 102 and the second edge portion 202 are connected to form a connecting layer 20, the first groove 1221 and the second groove 1222 together constitute an opening 122. The opening 122 is connected to the accommodating cavity 140. The opening 122 can be a liquid injection port or a vacuum port. For example, a working medium can be injected into the accommodating cavity 140 through the opening 122, and the accommodating cavity 140 can be vacuumed through the opening 122, and then the opening 122 can be sealed, so that the accommodating cavity 140 is in a vacuum negative pressure state. Similarly, the working medium in the accommodating cavity 140 is also in a negative pressure state. The working medium in the negative pressure state is more easily vaporized after being heated. After the aforementioned opening 122 is sealed, the airtightness of the accommodating cavity 140 is less than or equal to 10 -5 Pa·m 3 / s, meeting the airtightness requirement of the temperature homogenizer 100.

[0100] The connection layer 20 may not include the opening 122. The present embodiment does not limit the process for sealing the opening 122. For example, the opening 122 may be sealed by ultrasonic welding. It is understood that in other embodiments, the opening 122 may be located elsewhere on the vapor chamber 100.

[0101] Exemplarily, the accommodating cavity 140 is filled with a working fluid. The working fluid is also called a cooling medium. Exemplarily, the material of the working fluid includes at least one of deionized water, acetone, ethanol, and fluorocarbons. When heat is transferred to the accommodating cavity 140 through the first cover plate 110 or the second cover plate 120. The working fluid in a negative pressure state vaporizes after being heated, and the vaporized working fluid flows to an area with a lower temperature. After being cooled, it condenses and releases heat, and returns under the capillary force of the capillary structure 130, realizing a heat transfer cycle. In the embodiment where the materials of the first metal layer 111 and the second metal layer 121 are both copper, deionized water, ethanol, and fluorocarbons do not chemically react with copper, and copper has little effect on the thermal cycle of the aforementioned working fluid.

[0102] The embodiment of the present application does not limit the shape of the temperature equalizing plate 100. For example, the temperature equalizing plate 100 can be square, circular, oval or irregular in shape. Obviously, the shape of the first cover plate 110 and the shape of the second cover plate 120 are set according to the shape of the temperature equalizing plate 100. The first cover plate 110 and the second cover plate 120 can also be square, circular, oval or irregular in shape. The shape of the first metal layer 111 is the same as that of the first cover plate 110. The shape of the second metal layer 121 is the same as that of the second cover plate 120. The embodiment of the present application does not limit this.

[0103] Accordingly, the shapes of the first main body 101 and the second main body 201 are configured based on the shape of the accommodating cavity 140. The first edge portion 102 is disposed around the periphery of the first main body 101, and its shape is configured based on the shape of the first main body 101. Similarly, the shape of the second edge portion 202 is configured based on the shape of the second main body 201.

[0104] The present embodiment does not limit the thickness of the first cover plate 110. The thickness of the first cover plate 110 is the dimension of the first cover plate 110 along the z-direction. For example, the thickness of the first cover plate 110 is 0.01 mm to 0.5 mm. For example, the thickness of the first cover plate 110 can be 0.01 mm, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, or 0.5 mm.

[0105] The embodiment of the present application does not limit the thickness of the second cover plate 120. For example, the thickness of the second cover plate 120 is 0.01mm-0.5mm. It is understandable that the embodiment of the present application does not limit the ratio of the thickness of the first cover plate 110 and the second cover plate 120. In some embodiments, the thickness of the first cover plate 110 is equal to (1±0.2) times the thickness of the second cover plate 120. For example, the thickness of the first cover plate 110 is 0.8 times, 0.9 times, 0.95 times, 1 times, 1.05 times, 1.1 times, 1.15 times or 1.2 times the thickness of the second cover plate 120. In this way, the difference in thickness between the first cover plate 110 and the second cover plate 120 is small, and the difference in stress between the first edge portion 102 and the second edge portion 202 is small. In the usage scenario where the temperature homogenizing plate 100 is bent, the bending has little effect on the connection performance of the first edge portion 102 and the second edge portion 202 , effectively improving the problem of poor toughness, delamination or tearing between the first edge portion 102 and the second edge portion 202 .

[0106] It is understood that in other embodiments, the thickness ratio of the first cover plate 110 to the second cover plate 120 may not be within the above range. For example, the thickness of the first cover plate 110 may be 0.4 times, 1.5 times, or 2 times the thickness of the second cover plate 120. This ratio can be set based on the usage scenario of the vapor chamber 100.

[0107] As described above, the first cover plate 110 includes a first metal layer 111, and the second cover plate 120 includes a second metal layer 121. Obviously, in embodiments where the first cover plate 110 includes only the first metal layer 111, the thickness of the first cover plate 110 is equal to the thickness of the first metal layer 111. Similarly, in embodiments where the second cover plate 120 includes only the second metal layer 121, the thickness of the second cover plate 120 is equal to the thickness of the second metal layer 121. In the embodiments of the present application, the first cover plate 110 is not limited to the first metal layer 111. The second cover plate 120 is also not limited to the second metal layer 121.

[0108] Figure 5a is a schematic cross-sectional view taken at point DD in Figure 2a. In Figure 5a, first cover plate 110 includes only first metal layer 111, and second cover plate 120 includes only second metal layer 121. In Figure 5a, the thickness of first metal layer 111 is equal to the thickness of first cover plate 110. The thickness of second metal layer 121 is equal to the thickness of second cover plate 120.

[0109] Figure 5b is a schematic cross-sectional view of another embodiment of the structure shown in Figure 2a at position DD. In Figure 5b, first cover plate 110 further includes a support layer 112, which is connected to the side of first metal layer 111 away from second metal layer 121. The provision of support layer 112 can increase the thickness of first cover plate 110. Furthermore, the mechanical strength and thickness of support layer 112 can be adjusted to adjust the strength and thickness of first cover plate 110.

[0110] The embodiment of the present application does not limit the material of the support layer 112. For example, the material of the support layer 112 includes at least one of copper and its alloys, titanium and its alloys, aluminum and its alloys, magnesium and its alloys, and steel. The embodiment of the present application does not limit the carbon content, iron content, and trace element content of the aforementioned steel. It can be set according to the type of steel. For example, the steel can be austenitic stainless steel such as 201 steel, 304 steel, 316 steel, or 310 steel, or ferritic stainless steel such as 430 steel or 446 steel. The following description uses copper as the material of the first metal layer 111 as an example. In this way, there are many choices of materials for the support layer 112.

[0111] In some embodiments, the material of the support layer 112 includes steel with a nitrogen content greater than 5%. Steel with a nitrogen content greater than 5% can improve the strength of the first cover plate 110, thereby improving the strength of the vapor chamber. In this way, the vapor chamber can be used to support electronic components in electronic devices, or the vapor chamber can be considered part of the midframe.

[0112] In some embodiments, grains with a grain size of 50 μm or less in the support layer 112, which is at least 5 mm long, account for 70% of the total grains. Similarly, the length of the support layer 112 is the dimension of the support layer 112 perpendicular to the z-direction. This ensures uniform material within the support layer 112 and minimizes internal stress. In other embodiments, the grain size of the support layer 112 may not be subject to the aforementioned limitations.

[0113] In some embodiments, the material of the support layer 112 is the same as the material of the first metal layer 111. In other embodiments, the material of the support layer 112 may be different from the material of the first metal layer 111. For example, in some embodiments, the material of the first metal layer 111 is copper, and the material of the support layer 112 is stainless steel (such as 304 steel or 316 steel). The copper layer isolates the accommodating cavity 140 and the stainless steel to prevent some elements in the stainless steel (such as carbon, nickel, nitrogen, etc.) from entering the accommodating cavity 140 and generating non-condensable gas with the working fluid, thereby reducing the heat dissipation performance of the temperature equalizing plate 100. In addition, the density of copper is 8.8g / cm 3 , the density of stainless steel is 7.9g / cm 3 The stainless steel layer can reduce the weight of the first cover plate 110. The stainless steel has a greater hardness, which can improve the supporting performance of the first cover plate 110.

[0114] In the embodiment of the present application, the support layer 112 covers the entire side of the first metal layer 111 away from the second metal layer 121. In other words, the vertical projection of the support layer 112 on the surface of the first metal layer 111 overlaps the surface of the first metal layer 111. In other embodiments, the support layer 112 may only cover a portion of the first metal layer 111.

[0115] The embodiment of the present application does not limit the connection method between the support layer 112 and the first metal layer 111. Exemplarily, the support layer 112 and the first metal layer 111 are formed by cold rolling.

[0116] In Figure 5b, the second cover plate 120 may also include a support layer 112. In other words, the temperature vapor chamber includes two support layers 112: one support layer 112 is located within the first cover plate 110, and the other support layer 112 is located within the second cover plate 120. The support layer 112 in the second cover plate 120 is connected to the side of the second metal layer 121 facing away from the first metal layer 111. Parameters such as the material and thickness of the support layer 112 in the second cover plate 120 can be the same as or different from those of the support layer 112 in the first cover plate 110.

[0117] In the example of FIG5b , the thickness of the first metal layer 111 can be much smaller than the thickness of the first cover plate 110 . For example, the thickness of the first metal layer 111 is 5 μm to 80 μm. In some embodiments, the thickness of the first metal layer 111 can be 5 μm to 10 μm. For example, the thickness of the first metal layer 111 can be 5 μm, 6 μm, 7 μm, 8 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 60 μm, 70 μm, or 80 μm, etc. In this way, because the size of 70% or more of the grains in the first edge portion 102 is less than or equal to 50μm, even if the thickness of the first metal layer 111 is only 5μm, the connection performance at the connection between the first edge portion 102 and the second edge portion 202 is better, and the first metal layer 111 can better isolate substances that may produce non-condensable gases from entering the accommodating cavity 140, so that the temperature spreader has excellent heat dissipation performance.

[0118] In some embodiments, in order to further reduce the density of the vapor chamber, the vapor chamber may include a polymer material.

[0119] Figure 5c is a schematic cross-sectional view of another embodiment of the device shown in Figure 2a at position DD. In Figure 5c, first cover plate 110 further includes a polymer layer 113, which is connected to the side of first metal layer 111 facing away from second metal layer 121. Polymer layer 113 and first metal layer 111 are stacked along the z-direction. Polymer layer 113 reduces the weight of first cover plate 110, thereby reducing the weight of the entire vapor chamber, contributing to lightweighting of the vapor chamber and the electronic device incorporating it.

[0120] Furthermore, the uniform and small-sized grains in the first edge portion 102 can prevent the polymer layer 113 from penetrating the first edge portion 102 and affecting the connection between the first edge portion 102 and the second edge portion 202. Furthermore, the uniform and small-sized grains in the first metal layer 111 can prevent the polymer layer 113 from entering the accommodating cavity 140, thereby preventing the polymer layer 113 from releasing non-condensable gases within the accommodating cavity 140 and affecting the heat dissipation performance of the vapor chamber 100.

[0121] Exemplarily, the material of the polymer layer 113 includes polyimide (PI), polypropylene (PP), polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polydimethylsiloxane (PDMS), polyethylene (PE), polypropylene carbonate (PPC), polyviny chloride (PVC), polyvinylidene chloride (PVdC), polystyrene (PS), polyamide (PA), etc.

[0122] In the embodiment of the present application, the polymer layer 113 covers the entire side of the first metal layer 111 away from the second metal layer 121. In other words, the vertical projection of the polymer layer 113 on the surface of the first metal layer 111 overlaps with the surface of the first metal layer 111.

[0123] In Figure 5c, the second cover plate 120 may also include a polymer layer 113. Alternatively, the second cover plate 120 may include the support layer 112 described in the example of Figure 5b.

[0124] Figure 5d is a cross-sectional schematic diagram of another embodiment of the DD portion of Figure 2a. In Figure 5d, the first cover plate 110 includes a first metal layer 111, a polymer layer 113, and a support layer 112, which are stacked sequentially along the z-direction. The support layer 112 provides excellent support strength for the first cover plate 110, the polymer layer 113 reduces the weight of the first cover plate 110, and the first metal layer 111 prevents the formation of non-condensable gas within the accommodating cavity 140, which would otherwise reduce the heat dissipation performance of the heat spreader. In addition, the connection between the first metal layer 111 and the second metal layer 121 also provides excellent connection performance at the connection between the first cover plate 110 and the second cover plate 120.

[0125] 5d, the polymer layer 113 is located between the first metal layer 111 and the support layer 112. In other embodiments, the support layer 112 may be located between the polymer layer 113 and the first metal layer 111. In other words, the first metal layer 111, the support layer 112, and the polymer layer 113 are stacked sequentially along the z-direction.

[0126] In Figure 5d, the second cover plate 120 may also include a polymer layer 113 and a first metal layer 111. It is understood that in other embodiments, the second cover plate 120 may also have the structure shown in Figure 5a, Figure 5b or Figure 5c.

[0127] The embodiment of the present application does not limit the number of support layers 112 and the number of polymer layers 113 in the first cover plate 110. For example, the number of support layers 112 can be one, two, three or more. The number of polymer layers 113 can be one, two, three or more. In the embodiment where the number of support layers 112 is multiple, the parameters such as the materials and dimensions of the multiple support layers 112 can be the same or different. In addition, in the embodiment where the support layer 112 and the polymer layer 113 are both multi-layered, the embodiment of the present application does not limit the arrangement of the polymer layer 113 and the support layer 112. For example, one support layer 112 can be provided between two adjacent polymer layers 113, or two or three support layers 112 can be provided between two adjacent polymer layers 113.

[0128] Returning to FIG. 2 b , the capillary structure 130 is located in the accommodating cavity 140 and connected to the first main body 101 .

[0129] The present embodiment does not limit the material of the capillary structure 130. For example, the material of the capillary structure 130 includes at least one of aluminum and its alloys, stainless steel, titanium and its alloys, carbon fiber, graphene, graphite, copper and its alloys, and polymer materials.

[0130] The embodiments of the present application do not limit the connection method between the capillary structure 130 and the first main body 101. In some embodiments, the capillary structure 130 and the first main body 101 are connected as an integrally formed part. For example, the first main body 101 and the capillary structure 130 are formed on the first main body 101 by etching or laser processing. In this way, the connectivity between the capillary structure 130 and the first main body 101 is excellent, and the capillary structure 130 and the first main body 101 are not easy to separate. In the scenario where the temperature equalizing plate 100 is bent, the integrally formed first main body 101 and the capillary structure 130 can effectively reduce the friction generated by the relative movement of the capillary structure 130 and the first main body 101 during the bending of the temperature equalizing plate 100. If the first main body 101 is bent, the capillary structure 130 and the first main body 101 are not easy to delaminate or tear.

[0131] In other embodiments, the capillary structure 130 and the first body portion 101 are connected by heat treatment. For example, in an embodiment where the capillary structure 130 is a mesh structure, foamed metal, or metal powder, the capillary structure 130 and the first body portion 101 are connected by sintering or heat treatment.

[0132] In some embodiments of the present application, the distance between the capillary structure 130 and the inner edge of the first edge portion 102 is 1 mm to 3 mm. For example, the distance between the capillary structure 130 and the inner edge of the first edge portion 102 is 1 mm, 2 mm, or 3 mm. The inner edge of the first edge portion 102 is the edge where the first edge portion 102 and the first main body portion 101 are connected. Alternatively, the inner edge of the first edge portion 102 is the area where the first edge portion 102 and the second edge portion 202 are directly connected and close to the edge of the accommodating cavity 140. The distance between the capillary structure 130 and the inner edge of the first edge portion 102 is the distance between the capillary structure 130 and the inner edge of the first edge portion 102 along a direction perpendicular to the z-direction. Since the first edge portion 102 and the second edge portion 202 are connected, it is clear that the distance between the inner edges of the capillary structure 130 and the second edge portion 202 is the same as the distance between the capillary structure 130 and the inner edge of the first edge portion 102. The distance between the capillary structure 130 and the inner edge of the first edge portion 102 is within the above range, and the connection process between the first edge portion 102 and the second edge portion 202 has little impact on the capillary structure 130, thereby avoiding the connection process from affecting the capillary force of the portion of the capillary structure 130 near the first edge portion 102.

[0133] In Figure 2b, the temperature spreader 100 also includes: a plurality of protrusions 150, and the plurality of protrusions 150 are arranged at intervals in the accommodating cavity 140. One end of the plurality of protrusions 150 is connected to the second main body 201, and the other end of the plurality of protrusions 150 is a free end. The plurality of protrusions 150 can increase the surface area in the accommodating cavity 140, increase the contact area between the working fluid and the accommodating cavity 140, and make it easier for the working fluid to adhere to the accommodating cavity 140. Secondly, the protrusions 150 have a drainage effect on the working fluid in a gaseous state. In addition, the protrusions 150 also have a drainage effect. The working fluid attached to the surface of the protrusions 150 can flow and converge along the surface of the protrusions 150, which is beneficial to shorten the time of the thermal cycle of the working fluid and increase the heat dissipation performance of the temperature spreader.

[0134] The embodiments of the present application do not limit the positional relationship between the protrusion 150 and the capillary structure 130. In some embodiments, the end of the protrusion 150 away from the second main body 201 contacts the end of the capillary structure 130 away from the first main body 101. In this way, the working fluid attached to the protrusion 150 flows to the free end of the protrusion 150 and then enters the capillary structure 130 for circulation under the action of the capillary structure 130. In addition, the end of the protrusion 150 contacts the end of the capillary structure 130 to reduce the thickness of the temperature equalizing plate. It is understandable that in other embodiments, there may be a gap between the end away from the second main body 201 and the end of the capillary structure 130 away from the first main body 101.

[0135] The present embodiment does not limit the arrangement of the plurality of protrusions 150. In some embodiments, the plurality of protrusions 150 are arranged in an orderly manner, for example, in a circular row or rectangular array distributed on the second main body 201. In other embodiments, the plurality of protrusions 150 may be arranged in a disordered manner. Furthermore, the dimensions of each protrusion 150 along the z-direction may be the same or different, and this is not limited in the present embodiment.

[0136] In some embodiments, the material of the protrusion 150 is the same as that of the second metal layer 121. The protrusion 150 does not chemically react with the working medium in the accommodation cavity 140 to generate non-condensable gas, thereby preventing the non-condensable gas from affecting the heat dissipation performance of the vapor chamber.

[0137] The embodiment of the present application does not limit the connection method between the protrusion 150 and the second main body 201. For example, the protrusion 150 and the second main body 201 are connected as an integrally formed part. For example, in Figure 2b, the protrusion 150 and the second main body 201 are formed on the second main body 201 by etching or laser processing. The connection performance between the protrusion 150 and the second main body 201 is excellent. In addition, the process of etching or laser processing to form the protrusion 150 has little effect on the surface shape of the second main body 201 away from the protrusion 150. The surface of the second main body 201 away from the protrusion 150 is relatively flat. In Figure 2b, the surface e1 of the second cover plate 120 away from the protrusion 150 is a plane.

[0138] In some embodiments, a reinforcing rib may be provided between the first cover plate 110 and the second cover plate 120. The reinforcing rib is located within the accommodating cavity 140, with one end of the reinforcing rib connected to the first cover plate 110 and the other end of the reinforcing rib connected to the second cover plate 120. The reinforcing rib can increase the structural strength of the vapor chamber 100 and improve the support performance of the vapor chamber 100.

[0139] Figure 6a is a schematic diagram of the internal structure of another heat spreader 100 provided in an embodiment of the present application. In Figure 6a, the protrusion 150 and the second main body 201 are formed by stamping. During the stamping process, the surface of the second main body 201 facing away from the protrusion 150 is altered by the stamping. For example, in Figure 6a, the surface of the second main body 201 facing away from the protrusion 150 has multiple pits, resulting in an uneven surface.

[0140] In the embodiment where the second cover plate 120 includes the support layer 112, the support layer 112 and the second body portion 201 are stamped together to form the second body portion 201 on the inner wall of the accommodating cavity 140. In FIG6a, the surface e2 of the second cover plate 120 facing away from the protrusion 150 has a recess.

[0141] It is understandable that in some embodiments of the present application, the protrusion 150 is not necessary, and the vapor chamber 100 may not be provided with the protrusion 150 .

[0142] As mentioned above, the temperature equalizer 100 can be connected to the printed circuit board 13 of the electronic device 10. Exemplarily, the first cover plate 110 of the temperature equalizer 100 is closer to the printed circuit board 13 than the second cover plate 120. For example, the surface of the first cover plate 110 facing away from the second cover plate 120 is in contact with the printed circuit board 13, and the second cover plate 120 is located on the side of the temperature equalizer 100 away from the printed circuit board 13. When the electronic device 10 is working, the heat on the printed circuit board 13 is transferred to the accommodating cavity 140 through the first cover plate 110. The working fluid in the accommodating cavity 140 absorbs the heat and vaporizes. The working fluid in the accommodating cavity 140 releases heat and liquefies after reaching the inner surface of the second cover plate 120. Under the action of the protrusion 150 and the capillary structure 130, the working fluid returns to the inner surface of the first cover plate 110 for the next thermal cycle.

[0143] In the embodiments of the present application, the first cover plate 110 and the printed circuit board 13 are not limited to being directly connected. For example, the first cover plate 110 and the printed circuit board 13 may be indirectly connected via other structures. For example, the first cover plate 110 and the printed circuit board 13 may be connected via a thermally conductive adhesive layer. In some embodiments, a graphite layer may be further disposed between the first cover plate 110 and the printed circuit board 13.

[0144] As described above, in the embodiment where the temperature vapor chamber 100 and the printed circuit board 13 are located on opposite sides of the middle frame 14, part of the temperature vapor chamber 100 passes through the middle frame 14 and is connected to the printed circuit board 13, or part of the printed circuit board 13 passes through the middle frame 14 and is connected to the temperature vapor chamber 100.

[0145] In some embodiments, the printed circuit board 13 has a high-heat zone. When the electronic device 10 is in operation, the temperature of the high-heat zone is higher than that of the rest of the printed circuit board 13. A portion of the vapor chamber 100 extends through the middle frame 14 and abuts against the high-heat zone. Alternatively, the high-heat zone extends through the middle frame 14 and abuts against the vapor chamber 100. The working fluid within the vapor chamber 100 absorbs the heat from the high-heat zone and dissipates it.

[0146] Exemplarily, as shown in FIG1a, a through hole 17 is provided on the middle frame 14, and the through hole 17 penetrates the middle frame 14 along the thickness direction of the middle frame 14. The first cover plate 110 (as shown in FIG5) is connected to the printed circuit board 13 through the through hole 17. For example, the first cover plate 110 is connected to the high-temperature zone of the printed circuit board 13 through the through hole 17. In this way, it is beneficial to reduce the total thickness of the middle frame 14 and the temperature equalizer 100, improve the integration of the electronic device 10, and facilitate the miniaturization of the electronic device 10. In addition, the temperature equalizer 100 can be regarded as a part of the middle frame 14, and the temperature equalizer 100 provides supporting strength for supporting structures such as the display screen 12, so that the temperature equalizer 100 can take into account multiple functions.

[0147] The embodiment of the present application does not limit the shape of the through hole 17. For example, it can be circular, square, oval or irregular in shape. The position of the through hole 17 can be set according to the position of the high heat zone mentioned above, and the embodiment of the present application does not limit this.

[0148] In some embodiments, the through hole 17 is relatively large, for example, the through hole 17 is similar in size to the vapor chamber 100 . The vapor chamber 100 is connected to the through hole 17 , and the vapor chamber 100 can be considered as a part of the middle frame 14 .

[0149] Figure 1b is a schematic diagram of the structure of the middle frame 14 and the vapor chamber 100 according to an embodiment of the present application. Referring to Figure 1b , the inner wall of the through hole 17 has a stepped surface 171. The vapor chamber 100 is positioned within the through hole 17. The outer periphery of the vapor chamber 100 rests on and is connected to the stepped surface 171. For example, the outer periphery of the vapor chamber 100 is bonded, welded, or screwed to the stepped surface 171.

[0150] In this way, the vapor chamber 100 can replace part of the middle frame 14 and provide support. This can increase the integration of the middle frame 14 and the vapor chamber 100. The volume occupied by the middle frame 14 and the vapor chamber 100 can be reduced. This allows the vapor chamber 100 to provide both heat dissipation and support. The dimensions of the middle frame 14 and the vapor chamber 100 along the z-direction can be reduced, for example, by reducing the combined thickness of the middle frame 14 and the vapor chamber 100 along the z-direction by 0.1 mm or more, thereby improving the integration of the middle frame 14 and the vapor chamber 100.

[0151] Figure 6b is a schematic diagram of the internal structure of another thermal barrier 100 provided in an embodiment of the present application. The difference between Figure 6b and Figure 2a is that the second cover plate 120 in Figure 6b is provided with a protrusion 160, which is provided in a direction away from the first cover plate 110. In an embodiment in which a portion of the thermal barrier 100 extends through the middle frame 14 and is connected to the printed circuit board 13, the protrusion 160 can extend through the middle frame 14 and be connected to the printed circuit board 13. For example, the protrusion 160 extends through the through hole 17 of the middle frame 14 shown in Figure 1a and is connected to the printed circuit board 13.

[0152] It is understood that the protrusion 160 may be provided on the first cover plate 110 . Alternatively, the protrusion 160 may be provided on both the first cover plate 110 and the second cover plate 120 .

[0153] The temperature homogenizing plate 100 can be connected to the remaining structures of the electronic device 10 in the same manner as that of the printed circuit board 13 , which will not be described in detail here.

[0154] The embodiment of the present application does not limit the manufacturing process of the vapor chamber 100. The following illustrates a portion of the manufacturing process of the vapor chamber 100 in conjunction with FIG7a.

[0155] FIG7a is a process flow chart of a heat spreader 100 provided in an embodiment of the present application. Referring to FIG7a, the process for preparing the heat spreader 100 includes:

[0156] s1. Provide the first cover plate 110, the second cover plate 120 and the capillary structure 130 shown in FIG. 2b.

[0157] The structures and materials of the first cover plate 110 , the second cover plate 120 and the capillary structure 130 refer to the description in FIG. 2 b and are not described again here.

[0158] s2. As shown in FIG7 b , a first heat treatment is performed on the first cover plate 110 , the capillary structure 130 , and the second cover plate 120 stacked in sequence to connect the first edge portion 102 and the second edge portion 202 .

[0159] The structure after executing step s2 in FIG7a is shown in FIG2b , wherein the first edge portion 102 and the second edge portion 202 are connected to form a connection layer 20 . The structure of the connection layer 20 is described above and will not be repeated here.

[0160] Wherein, the temperature of the first heat treatment in s2 is 150℃-400℃, the pressure is greater than or equal to 30MPa (megapascals), and the time is greater than or equal to 30min (minutes). In some embodiments, the pressure of the first heat treatment is 30MPa-200MPa, and the time is 30min-100min. Exemplarily, the temperature of the first heat treatment can be 150℃, 170℃, 180℃, 190℃, 200℃, 210℃, 220℃, 240℃, 260℃, 270℃, 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, 380℃ or 400℃. The pressure of the first heat treatment can be 30 MPa, 40 MPa, 50 MPa, 60 MPa, 70 MPa, 80 MPa, 90 MPa, 100 MPa, 110 MPa, 120 MPa, 140 MPa, 150 MPa, 160 MPa, 170 MPa, 180 MPa, 190 MPa, 200 MPa, 250 MPa, 350 MPa or 500 MPa, etc. The time of the first heat treatment can be 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 130 min, 150 min, 180 min or 300 min, etc.

[0161] Exemplarily, the first heat treatment of the first cover plate 110 , the capillary structure 130 , and the second cover plate 120 is performed in a container, such as a sintering furnace.

[0162] Illustratively, during the first heat treatment, the first cover plate 110 , the capillary structure 130 and the second cover plate 120 are all treated in a protective atmosphere, wherein the protective gas may be nitrogen or helium, for example.

[0163] It is understood that the present embodiment is not limited to the temperature being constant during the first heat treatment. For example, the temperature variation during the first heat treatment is within 15° C. Similarly, the pressure variation during the first heat treatment can be within 10 MPa.

[0164] In the example of Figure 7a , after the first heat treatment, the first edge portion 102 and the second edge portion 202 are connected. After connection, the first main body portion 101 and the second main body portion 201 together enclose the accommodating cavity 140. The first heat treatment is performed at a relatively low temperature, effectively alleviating the problem of high-temperature-induced deformation and oxidation of the first and second cover plates 110 and 120.

[0165] Furthermore, due to the relatively low temperature, the first heat treatment process has a relatively low impact on the hardness and yield strength of the first and second cover plates 110, 120. For example, after the first and second cover plates 110, 120 are connected, the hardness of the first cover plate 110 decreases by less than or equal to 20%, and the yield strength decreases by less than or equal to 20%. Similarly, after the first and second cover plates 110, 120 are connected, the hardness of the second cover plate 120 decreases by less than or equal to 20%, and the yield strength decreases by less than or equal to 20%.

[0166] Secondly, the higher pressure during the first heat treatment causes atoms to diffuse and mix between the first edge portion 102 and the second edge portion 202, forming a connection layer 20 with strong bonding strength. Furthermore, more than 70% of the grains in the connection layer 20 are smaller than 50 μm. The grains in the connection layer 20 are uniform and fine, resulting in low internal stress in the connection layer 20, making it less susceptible to delamination or brittle cracking.

[0167] Furthermore, in an embodiment where the material of the support layer 112 is stainless steel, the temperature of the first heat treatment is low, the diffusion distance of trace elements (such as aluminum) in the stainless steel is small, and the trace elements entering the accommodating cavity 140 produce less non-condensable gas, thereby improving the heat dissipation performance of the temperature equalizer.

[0168] In the embodiment where the first cover plate 110 includes a polymer layer 113 (as shown in FIG5 d ), the temperature of the first heat treatment is relatively low, effectively alleviating the problems of cracking, blackening, or delamination of the polymer material in the polymer layer 113 caused by high temperature. The same is true for the embodiment where the second cover plate 120 includes a polymer layer.

[0169] In addition, even if the thickness of the first metal layer 111 is relatively small, for example, 5 μm, the first heat treatment has a relatively low temperature, so the first heat treatment has a relatively small effect on the physical properties of the thinner first metal layer 111, such as hardness.

[0170] Furthermore, the temperature of the first heat treatment is relatively low, and the micro-nano structures (such as barbs or pores) on the surface of the capillary structure 130 are not easily collapsed or melted during the first heat treatment. The better capillary force of the capillary structure 130 can also improve the heat dissipation performance of the vapor chamber.

[0171] In some embodiments, if there is dust or impurities on the surfaces of the first cover plate 110 and the second cover plate 120 , the first cover plate 110 and the second cover plate 120 may be cleaned to remove the impurities or dust before executing step s1 in FIG. 7 a .

[0172] For example, in an embodiment where the surface of the first cover plate 110 or the surface of the second cover plate 120 includes an oxide layer such as copper oxide, the oxide layer on the surface of the first cover plate 110 or the surface of the second cover plate 120 may be removed before executing step s1 in FIG. 7 a .

[0173] It is understandable that in some embodiments, after executing s2 in Figure 7a, it can also include injecting a working medium into the accommodating chamber 140, evacuating the accommodating chamber 140 to put the accommodating chamber 140 in a vacuum negative pressure state, and sealing the opening 122 of the accommodating chamber 140 (as shown in Figure 2b).

[0174] In the embodiment where the temperature vapor chamber 100 includes the protrusion 150, the protrusion 150 may be provided on the first cover plate 110. Methods for providing the protrusion 150 include, but are not limited to, stamping, laser processing, or etching.

[0175] In this embodiment, the capillary structure 130 and the first main body 101 of the first cover plate 110 may be in a connected state. In some embodiments, the capillary structure 130 and the first main body 101 of the first cover plate 110 may be in a disconnected state, and step s3 in FIG. 7 a may be performed to connect the capillary structure 130 and the first main body 101 of the first cover plate 110. In other words, step s3 in FIG. 7 a is an optional process. If the capillary structure 130 and the first cover plate 110 are in a disconnected state, the following steps may be performed after step s1 and before step s2:

[0176] s3. As shown in FIG. 7 c , a second heat treatment is performed on the first cover plate 110 and the capillary structure 130 to connect the capillary structure 130 to the first main body 101 .

[0177] For example, in an embodiment where the capillary structure 130 is a mesh structure, foamed metal, or metal powder, after step s3 is executed, the capillary structure 130 is connected to the first main body 101. The structure of the first cover plate 110 and the capillary structure 130 after step s3 is shown in FIG7b.

[0178] Wherein, the temperature of the second heat treatment is 150°C-400°C, the pressure is greater than or equal to 5 MPa, and the time is greater than or equal to 30 minutes. In some embodiments, the pressure of the second heat treatment is 5 MPa-200 MPa, and the time is 30 minutes-100 minutes. Exemplarily, the temperature of the second heat treatment can be 150°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 240°C, 260°C, 270°C, 300°C, 310°C, 320°C, 330°C, 340°C, 350°C, 380°C or 400°C. The pressure of the second heat treatment can be 5 MPa, 10 MPa, 20 MPa, 30 MPa, 40 MPa, 50 MPa, 70 MPa, 80 MPa, 100 MPa, 110 MPa, 120 MPa, 150 MPa, 160 MPa, 170 MPa, 180 MPa, 200 MPa, 250 MPa, 350 MPa or 500 MPa, etc. The time of the second heat treatment can be 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 130 min, 150 min, 180 min or 280 min, etc.

[0179] Exemplarily, the second heat treatment of the first cover plate 110 and the second cover plate 120 is performed in a container, such as a sintering furnace. The present embodiment is not limited to maintaining a constant temperature during the second heat treatment. Exemplarily, the temperature variation during the first heat treatment is within 15°C. Similarly, the pressure variation during the second heat treatment can be within 10 MPa.

[0180] Illustratively, during the second heat treatment process, the first cover plate 110 and the capillary structure 130 are both subjected to a protective atmosphere, wherein the protective gas may be, for example, nitrogen or helium.

[0181] Similar to the aforementioned first heat treatment, the second heat treatment is performed at a lower temperature. This process has a minimal impact on the capillary structure 130 and the first cover plate 110, allowing the first cover plate 110 to maintain good hardness and yield strength after the second heat treatment. During the second heat treatment, the amount of grain growth within the first cover plate 110 is minimal, and elements on the side of the first cover plate 110 facing away from the capillary structure 130 are less likely to diffuse to the side closer to the capillary structure 130. During the second heat treatment, the micro-nanostructures of the capillary structure 130 are less likely to collapse or deform, maintaining a strong capillary force and improving the heat dissipation performance of the vapor chamber.

[0182] In some embodiments of the present application, nanoparticles can be arranged between the first edge portion 102 and the second edge portion 202 before executing s2 to promote atomic diffusion between the surface of the first edge portion 102 and the surface of the second edge portion 202, so that the grain growth at the connection between the first edge portion 102 and the second edge portion 202 is faster, and the connection between the first edge portion 102 and the second edge portion 202 is completed in a shorter time.

[0183] In some embodiments, in order to rapidly fuse the grains on the surfaces of the first edge portion 102 and the second edge portion 202, the process may further include:

[0184] s4. As shown in FIG. 7 d , the first cover plate 110 , the capillary structure 130 and the second cover plate 120 are stacked, and nanoparticles are filled between the first edge portion 102 and the second edge portion 202 .

[0185] The nanoparticles facilitate rapid fusion of grains on the surfaces of the first edge portion 102 and the second edge portion 202 during the first treatment. The nanoparticles act as grain nuclei, shortening the nucleation time on the surfaces of the first edge portion 102 and the second edge portion 202 and shortening the formation time of the connecting layer.

[0186] Filling the nanoparticles between the first edge portion 102 and the second edge portion 202 may be, for example, placing the nanoparticles on the surface of the first edge portion 102 facing the second edge portion 202 ; or placing the nanoparticles on the surface of the second edge portion 202 facing the first edge portion 102 .

[0187] The present embodiment does not limit the material of the nanoparticles. For example, the nanoparticles may include at least one of titanium and its alloys, aluminum and its alloys, copper and its alloys, carbon, magnesium and its alloys. During the first heat treatment, the nanoparticles may serve as crystal nuclei to promote grain growth, thereby shortening the time it takes for the first edge portion 102 and the second edge portion 202 to connect.

[0188] Illustratively, the nanoparticles have a particle size of less than or equal to 10 μm. In some embodiments, the nanoparticles may have a particle size of 50 nm to 5 μm. For example, the nanoparticles may have a particle size of 50 nm, 100 nm, 200 nm, 400 nm, 500 nm, 700 nm, 800 nm, 1 μm, μm, 2 μm, 3 μm, 4 μm, or 5 μm, etc.

[0189] It is understood that the manufacturing process of the temperature vapor chamber 100 provided in the embodiment of the present application is not limited to the process shown in FIG7 a , and other processes may be used.

[0190] The temperature spreader of the embodiment of the present application may include a metal cover plate and a connecting layer, which is mainly composed of metal grains with relatively small grain size, and may have high strength and high stiffness characteristics on a macro scale; it may also include some non-metallic materials with high flexibility to meet the heat dissipation requirements of different electronic products.

[0191] In the description of this specification, specific features, structures, materials or characteristics may be combined in any appropriate manner in any one or more embodiments or examples. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit them. Although this application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments or replace some of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A heat pipe, characterized in that, The heat pipe includes: A first cover plate including a first metal layer, the first metal layer including a first main body portion and a first edge portion surrounding the outer periphery of the first main body portion; A second cover plate including a second metal layer, the second metal layer including a second main body portion and a second edge portion surrounding the outer periphery of the second main body portion; the surfaces of the first edge portion and the second edge portion are connected to form a connection layer, and the first main body portion and the second main body portion jointly enclose a receiving cavity; and A capillary structure located in the receiving cavity and connected to the first main body portion; Wherein, along a direction perpendicular to the thickness direction of the connection layer, the number of grains with a grain size less than or equal to 50 μm in at least 5 mm long of the connection layer accounts for 70% or more of the total number of grains.

2. The heat pipe according to claim 1, wherein The number of grains with a grain size less than or equal to 50 μm in the connection layer accounts for 70% or more of the total number of grains.

3. The heat pipe according to claim 1 or 2, characterized in that, The material of the first metal layer is a first metal material. The first edge portion has a first surface and a second surface arranged oppositely. The second surface is connected to the surface of the second edge portion. At a position where the distance from the first surface in the first edge portion is greater than or equal to 3 μm, the mass percentage of the first metal material is greater than or equal to 95%.

4. The heat pipe according to any one of claims 1-3, characterized in that, The first cover plate further includes a support layer, and the support layer is connected to the side of the first metal layer away from the second metal layer.

5. The heat pipe according to claim 4, characterized in that The material of the support layer includes at least one of titanium and its alloys, aluminum and its alloys, magnesium and its alloys, and steel.

6. The heat pipe according to any one of claims 1-5, characterized in that The first cover plate further includes a polymer layer, and the polymer layer is connected to the side of the first metal layer away from the second metal layer.

7. The heat pipe according to any one of claims 1-6, characterized in that The material of the first metal layer includes at least one of copper and its alloys, and aluminum and its alloys.

8. The heat pipe according to any one of claims 1-7, characterized in that The thickness of the first metal layer is 5 μm - 80 μm.

9. The heat pipe according to any one of claims 1-8, characterized in that The heat pipe further includes: a plurality of protrusions spaced apart in the receiving cavity, one ends of the plurality of protrusions are all connected to the second main body portion, and the other ends are all free ends.

10. The heat pipe according to any one of claims 1-9, characterized in that, The capillary structure and the first main body portion are connected as an integrally formed part.

11. A preparation method of a heat pipe, characterized in that, The preparation method of the heat pipe includes: Providing a first cover plate, a second cover plate, and a capillary structure. The first cover plate includes a first metal layer, the first metal layer including a first main body portion and a first edge portion surrounding the outer periphery of the first main body portion; the second cover plate includes a second metal layer, the second metal layer including a second main body portion and a second edge portion surrounding the outer periphery of the second main body portion; the capillary structure is connected to the first main body portion; Performing a first heat treatment on the first cover plate, the capillary structure, and the second cover plate sequentially stacked to connect the first edge portion and the second edge portion; Wherein, the temperature of the first heat treatment is 150°C - 400°C, the pressure is greater than or equal to 30 MPa, and the time is greater than or equal to 30 min - 100 min.

12. The preparation method of the heat pipe according to claim 11, wherein Before the step of performing the first heat treatment on the first cover plate, the capillary structure, and the second cover plate sequentially stacked, it further includes: Performing a second heat treatment on the first cover plate and the capillary structure to connect the capillary structure and the first main body portion; Among them, the temperature of the second heat treatment is 150°C - 400°C, the pressure is greater than or equal to 5 MPa, and the time is greater than or equal to 30 min.

13. The preparation method of the heat pipe according to claim 11 or 12, characterized in that Before the first heat treatment step for the first cover plate, the capillary structure, and the second cover plate that are sequentially stacked, the following steps are further included: Stack the first cover plate, the capillary structure, and the second cover plate, and fill nano-particles between the first edge portion and the second edge portion.

14. An electronic device, characterized in that, The electronic device includes a printed circuit board and the heat pipe according to any one of claims 1-10, and the first cover plate is connected to the printed circuit board.

15. The electronic device according to claim 14, wherein The electronic device further includes: a middle frame; the heat pipe, the middle frame, and the printed circuit board are sequentially stacked; a through hole penetrating the middle frame in the thickness direction of the middle frame is provided on the middle frame, and the first cover plate passes through the through hole and is connected to the printed circuit board.

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