Vapor chambers and electronic devices

Abstract

To provide a vapor chamber and an electronic device that can improve heat dissipation efficiency.SOLUTION: A vapor chamber comprises a body sheet 30, and a first sheet 20 laminated on the body sheet. The body sheet 30 includes: a vapor flow passage part through which vapor of working fluid passes; and a liquid flow passage part 60 communicating with the vapor flow passage part, and through which liquid of the working fluid passes. The vapor flow passage part includes a vapor passage extending along a first direction. The first sheet 20 includes: a first sheet inner surface facing the body sheet 30; and a first sheet groove 70 provided in the first sheet inner surface, provided at a position overlapping with the vapor passage in a planar view, and extending along a direction intersecting with the first direction.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present disclosure relates to a vapor chamber and an electronic device. [Background technology]

[0002] Heat-generating devices such as central processing units (CPUs), light-emitting diodes (LEDs), and power semiconductors used in mobile devices such as handheld devices and tablet computers are cooled by heat dissipation members such as heat pipes (see, for example, Patent Documents 1 and 2). In recent years, thinner heat dissipation members have been required to make mobile devices thinner, and vapor chambers, which can be made thinner than heat pipes, have been developed. A working fluid is sealed inside the vapor chamber, and the vapor chamber cools the device by having this working fluid absorb the heat from the device and disperse it inside.

[0003] More specifically, the working fluid in the vapor chamber receives heat from the device in the portion (evaporator) close to the device and evaporates into vapor (working vapor). The working vapor diffuses away from the evaporator in the vapor channel, cools, and condenses into liquid (working liquid). The vapor chamber is provided with a liquid channel portion with a capillary structure (wick), and the working liquid enters the liquid channel portion from the vapor channel portion and flows through the liquid channel portion toward the evaporator. The working liquid then receives heat again in the evaporator and evaporates. In this way, the working fluid circulates within the vapor chamber while repeatedly changing phases, i.e., evaporating and condensing, thereby transferring heat from the device and increasing heat dissipation efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-204841 [Patent Document 2] Patent No. 6877513 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure aims to provide a vapor chamber and an electronic device that can improve heat dissipation efficiency. [Means for solving the problem]

[0006] A first aspect of the present disclosure is A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a vapor flow path portion through which the vapor of the working fluid passes, and a liquid flow path portion that communicates with the vapor flow path portion and through which the liquid of the working fluid passes, the steam flow path portion includes a steam passage extending along a first direction, The first sheet is a vapor chamber including a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove being provided at a position overlapping with the vapor passage in a planar view and extending along a direction intersecting the first direction.

[0007] A second aspect of the present disclosure is a vapor chamber according to the first aspect, The liquid flow path portion may include a liquid flow path main groove extending along the first direction, The first seat groove may have a smaller cross-sectional area than the main liquid flow path groove.

[0008] A third aspect of the present disclosure is a vapor chamber according to the first aspect, The liquid flow path portion may include a liquid flow path main groove extending along the first direction, The first seat groove may have a larger cross-sectional area than the main liquid flow path groove.

[0009] A fourth aspect of the present disclosure is a vapor chamber according to each of the first to third aspects described above, The first sheet groove may be provided so as to extend to a position overlapping with the liquid flow path portion in a plan view.

[0010] A fifth aspect of the present disclosure is a vapor chamber according to the fourth aspect, The first seat groove may be provided so as to cross the steam passage in a direction intersecting the first direction.

[0011] A sixth aspect of the present disclosure is a vapor chamber according to the fourth aspect, The first seat groove may include a first end provided at a position overlapping the steam passage in a plan view, and a second end provided at a position overlapping the liquid flow path portion in a plan view.

[0012] A seventh aspect of the present disclosure is a vapor chamber according to the fourth aspect, The first sheet may include a plurality of the first sheet grooves, The plurality of first sheet grooves may include a first sheet groove arranged to cross the steam passage in a direction intersecting the first direction, and a first sheet groove including a first end provided at a position overlapping with the steam passage in a plan view and a second end provided at a position overlapping with the liquid flow path portion in a plan view.

[0013] An eighth aspect of the present disclosure is a vapor chamber according to each of the sixth aspect and the seventh aspect described above, The first seat groove may be formed so that a flow path cross-sectional area decreases from the second end toward the first end.

[0014] A ninth aspect of the present disclosure is a vapor chamber according to each of the sixth aspect and the seventh aspect described above, The first seat groove may be formed so that a flow path cross-sectional area decreases from the first end toward the second end.

[0015] A tenth aspect of the present disclosure is a vapor chamber according to any one of the sixth to ninth aspects described above, The first seat groove may be disposed so as to be inclined with respect to the first direction in a plan view.

[0016] An eleventh aspect of the present disclosure is a vapor chamber according to each of the sixth to tenth aspects described above, The first sheet may include a plurality of the first sheet grooves, The first seat grooves may be arranged radially in a plan view.

[0017] A twelfth aspect of the present disclosure is a vapor chamber according to each of the first to eleventh aspects described above, The first sheet may include a plurality of the first sheet grooves and a communication groove that connects adjacent first sheet grooves to each other.

[0018] A thirteenth aspect of the present disclosure is a vapor chamber according to any one of the first to twelfth aspects described above, The main body sheet may include a first main body surface facing the first sheet inner surface and a second main body surface located on the opposite side to the first main body surface, The liquid flow path portion may be provided on the first main body surface.

[0019] A fourteenth aspect of the present disclosure is a vapor chamber according to the thirteenth aspect, A second sheet may be laminated on the second main body surface of the main body sheet, The liquid flow path portion may also be provided on the second main body surface, The second sheet may include a second sheet inner surface facing the second main body surface, and a second sheet groove provided on the second sheet inner surface, the second sheet groove being provided at a position overlapping with the steam passage in a plan view and extending along a direction intersecting the first direction.

[0020] A fifteenth aspect of the present disclosure is a vapor chamber according to each of the first to fourteenth aspects described above, The first sheet may have a recessed area recessed toward the steam passage, The first seat groove may be disposed in the recessed region.

[0021] A sixteenth aspect of the present disclosure is a vapor chamber according to any one of the first to fifteenth aspects described above, The main body sheet may include a plurality of land portions extending along the first direction, in which the liquid flow path portions are provided, and a plurality of land portions aligned along a second direction perpendicular to the first direction, and a connecting portion connecting the land portions adjacent to each other, The first seat groove may be provided at a position facing the connecting portion.

[0022] A seventeenth aspect of the present disclosure is a vapor chamber according to any one of the first to sixteenth aspects described above, The main body sheet may include a plurality of land portions extending along the first direction, in which the liquid flow path portions are provided, and a plurality of land portions aligned along a second direction perpendicular to the first direction, and a connecting portion connecting the land portions adjacent to each other, The first seat groove may be provided in a region adjacent to the connecting portion along the first direction in a plan view.

[0023] An eighteenth aspect of the present disclosure is a vapor chamber according to any one of the first to seventeenth aspects described above, The vapor chamber may include a bent region bent along a bend line, The first seat groove may be disposed in the bending region.

[0024] A nineteenth aspect of the present disclosure is A vapor chamber in which a working fluid is sealed, a main body sheet including a first main body surface and a second main body surface located on the opposite side to the first main body surface; a first sheet located on the first main body surface of the main body sheet; a second sheet located on the second main body surface of the main body sheet; a space provided in the main body sheet, the space being covered by the first sheet and the second sheet; the main body sheet includes a plurality of land portions located within the space portion and extending in a first direction; the second sheet includes a second sheet outer surface located on the opposite side to the main body sheet, the vapor chamber includes a bent region bent along a bend line extending in a direction intersecting the first direction in a plan view, A second sheet outer surface recess is located on the second sheet outer surface in the bending region, forming a vapor chamber.

[0025] A twentieth aspect of the present disclosure is a vapor chamber according to the nineteenth aspect, The second sheet may be located on the inner side of the bend than the main body sheet.

[0026] A twenty-first aspect of the present disclosure is a vapor chamber according to each of the nineteenth aspect and the twentieth aspect, The second sheet outer surface recess may extend along the bending line and cross the space.

[0027] A twenty-second aspect of the present disclosure is a vapor chamber according to the twenty-first aspect, In the bending region, a plurality of the second sheet outer surface recesses may be located on the second sheet outer surface, The second sheet outer surface recesses may be aligned in the first direction.

[0028] A twenty-third aspect of the present disclosure is a vapor chamber according to each of the nineteenth aspect and the twentieth aspect, In the bending region, a plurality of the second sheet outer surface recesses may be located on the second sheet outer surface, The second sheet outer surface recesses may be aligned along the bending line, At least some of the second sheet outer surface recesses among the plurality of second sheet outer surface recesses may overlap the space.

[0029] A twenty-fourth aspect of the present disclosure is a vapor chamber according to any one of the nineteenth to twenty-third aspects, The bent line may extend in a direction perpendicular to the first direction in a plan view.

[0030] A twenty-fifth aspect of the present disclosure is a vapor chamber according to any one of the nineteenth to twenty-third aspects, The bent line may extend in a direction inclined toward the first direction.

[0031] A twenty-sixth aspect of the present disclosure is a vapor chamber according to any one of the nineteenth to twenty-fifth aspects described above, The first sheet may include a first sheet outer surface located on the opposite side to the main body sheet, A first sheet outer surface recess may be located on the first sheet outer surface in the bent region.

[0032] A twenty-seventh aspect of the present disclosure is a vapor chamber according to any one of the nineteenth to twenty-sixth aspects, A land recess may be located on the first body surface or the second body surface of the land portion, The land recess may not be in communication with the space, The land recess may overlap the second sheet outer surface recess.

[0033] A twenty-eighth aspect of the present disclosure is a vapor chamber according to the twenty-seventh aspect, The land recess may extend further out than the second sheet outer surface recess on both sides in the first direction.

[0034] A twenty-ninth aspect of the present disclosure is A vapor chamber in which a working fluid is sealed, a main body sheet including a first main body surface and a second main body surface located on the opposite side to the first main body surface; a first sheet located on the first main body surface of the main body sheet; a second sheet located on the second main body surface of the main body sheet; a space provided in the main body sheet, the space being covered by the first sheet and the second sheet; the main body sheet includes a plurality of land portions located within the space portion and extending in a first direction; the second sheet includes a second sheet outer surface located on the opposite side to the main body sheet, The vapor chamber is divided into a first region, a second region, and a third region located between the first region and the second region in the first direction, In the third region, a second sheet outer surface recess is located on the second sheet outer surface, forming a vapor chamber.

[0035] A 30th aspect of the present disclosure is a vapor chamber according to the 29th aspect, The second sheet outer surface recess may extend in a direction intersecting the first direction in a plan view and cross the space.

[0036] A thirty-first aspect of the present disclosure is a vapor chamber according to the twenty-ninth aspect, In the third region, a plurality of the second sheet outer surface recesses may be located on the second sheet outer surface, The plurality of second sheet outer surface recesses may be arranged in a direction intersecting the first direction, and at least some of the plurality of second sheet outer surface recesses may overlap the space portion.

[0037] A thirty-second aspect of the present disclosure is Housing and a device contained within the housing; and and a vapor chamber according to any one of the first to thirty-first aspects, in thermal contact with the device. [Effects of the Invention]

[0038] According to the present disclosure, heat dissipation efficiency can be improved. [Brief explanation of the drawings]

[0039] [Figure 1] FIG. 1 is a schematic perspective view illustrating an electronic device according to a first embodiment. [Figure 2] FIG. 2 is a top view showing the vapor chamber according to the first embodiment. [Figure 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. [Figure 4] FIG. 4 is a top view of the lower sheet of FIG. [Figure 5] FIG. 5 is a bottom view of the upper sheet of FIG. [Figure 6] FIG. 6 is a top view of the wick sheet of FIG. [Figure 7] FIG. 7 is an enlarged cross-sectional view of a portion of FIG. [Figure 8] FIG. 8 is a top view of FIG. [Figure 9] FIG. 9 is a partially enlarged bottom view of FIG. 5 at a position corresponding to FIG. [Figure 10] 10 is a partially enlarged top view of the vapor chamber of FIG. 2 at the location where the wick sheet of FIG. 8 and the upper sheet of FIG. 9 overlap. [Figure 11]FIG. 11 is a cross-sectional view taken along line BB in FIG. [Figure 12] FIG. 12 shows a modification of FIG. [Figure 13] FIG. 13 shows a modification of FIG. [Figure 14] FIG. 14 shows a modification of FIG. [Figure 15] FIG. 15 shows another modified example of FIG. [Figure 16] FIG. 16 shows another modified example of FIG. [Figure 17] FIG. 17 shows a modification of FIG. [Figure 18] FIG. 18 shows another modified example of FIG. [Figure 19] FIG. 19 shows another modified example of FIG. [Figure 20] FIG. 20 shows another modified example of FIG. [Figure 21] FIG. 21 is a partially enlarged top view showing the vapor chamber according to the second embodiment. [Figure 22] FIG. 22 shows a modification of FIG. [Figure 23] FIG. 23 is a partially enlarged top view showing the vapor chamber according to the third embodiment. [Figure 24] FIG. 24 is a partially enlarged top view showing the vapor chamber according to the fourth embodiment. [Figure 25] FIG. 25 is a partially enlarged top view showing the vapor chamber according to the fifth embodiment. [Figure 26] FIG. 26 is a partially enlarged top view showing the vapor chamber according to the sixth embodiment. [Figure 27] FIG. 27 is a partially enlarged top view showing the vapor chamber according to the seventh embodiment. [Figure 28] FIG. 28 is a modification of FIG. [Figure 29] FIG. 29 shows another modified example of FIG. [Figure 30] FIG. 30 is a partially enlarged top view showing the vapor chamber according to the eighth embodiment. [Figure 31] FIG. 31 is a modification of FIG. [Figure 32] FIG. 32 is a partially enlarged top view showing the vapor chamber according to the ninth embodiment. [Figure 33] FIG. 33 is a modification of FIG. [Figure 34] FIG. 34 shows another modified example of FIG. [Figure 35] FIG. 35 is a partially enlarged cross-sectional view showing a vapor chamber according to the tenth embodiment. [Figure 36] FIG. 36 is a partially enlarged cross-sectional view showing the vapor chamber according to the eleventh embodiment. [Figure 37] FIG. 37 is a partially enlarged cross-sectional view showing a vapor chamber according to the twelfth embodiment. [Figure 38] FIG. 38 is a partially enlarged top view showing the vapor chamber according to the thirteenth embodiment. [Figure 39] FIG. 39 is a top view showing the vapor chamber according to the fourteenth embodiment. [Figure 40] FIG. 40 is a side view showing the vapor chamber bent along the bend line of FIG. [Figure 41] FIG. 41 shows a modification of FIG. [Figure 42] FIG. 42 is a schematic diagram showing an example of a vapor chamber according to the fifteenth embodiment. [Figure 43] FIG. 43 is a schematic diagram showing another example of the vapor chamber according to the fifteenth embodiment. [Figure 44] FIG. 44 is an external perspective view showing a vapor chamber according to the fifteenth embodiment. [Figure 45] FIG. 45 is a plan view of the vapor chamber shown in FIG. 42 before bending. [Figure 46] FIG. 46 is a cross-sectional view taken along line AA-AA in FIG. [Figure 47] FIG. 47 is a plan view showing the inner surface of the first sheet shown in FIG. [Figure 48]FIG. 48 is a plan view showing the inner surface of the second sheet shown in FIG. [Figure 49] FIG. 49 is a cross-sectional view taken along line BB-BB in FIG. [Figure 50] 50 is a partially enlarged plan view showing a modified example of the second sheet outer surface recess shown in FIG. [Figure 51] FIG. 51 shows a modification of FIG. [Figure 52] FIG. 52 shows another modified example of FIG. [Figure 53] FIG. 53 shows another modified example of FIG. [Figure 54] FIG. 54 shows another modified example of FIG. [Figure 55] FIG. 55 is a plan view showing the first main body surface of the wick sheet shown in FIG. [Figure 56] FIG. 56 is a plan view showing the second main body surface of the wick sheet shown in FIG. [Figure 57] FIG. 57 is an enlarged partial cross-sectional view of FIG. [Figure 58] FIG. 58 is a partial enlarged view of the liquid flow path portion shown in FIG. [Figure 59] FIG. 59 is a schematic cross-sectional view showing the bending region of the vapor chamber shown in FIG. [Figure 60] FIG. 60 is a partially enlarged plan view showing a modified example of the second sheet outer surface recess shown in FIG. [Figure 61] FIG. 61 is a modified example of FIG. [Figure 62] FIG. 62 shows another modified example of FIG. [Figure 63] FIG. 63 shows another modified example of FIG. [Figure 64] FIG. 64 is a schematic cross-sectional view showing a modified example of the curved region of the vapor chamber shown in FIG. [Figure 65] FIG. 65 is a partially enlarged plan view showing a modified example of the vapor chamber shown in FIG. [Figure 66] FIG. 66 is a cross-sectional view taken along line CC-CC in FIG. [Figure 67]FIG. 67 is an external perspective view showing a vapor chamber according to the sixteenth embodiment. [Figure 68] FIG. 68 is a plan view of the vapor chamber shown in FIG. 67 before bending. [Figure 69] FIG. 69 is a partially enlarged cross-sectional view showing a vapor chamber according to the seventeenth embodiment. [Figure 70] 70 is a partially enlarged plan view showing the second sheet outer surface recess and the land recess shown in FIG. 69. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0040] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Note that in the drawings attached to this specification, the scale and aspect ratios have been appropriately changed and exaggerated from those of the actual objects for the convenience of illustration and ease of understanding. Furthermore, configurations shown in some drawings may be omitted in other drawings.

[0041] Furthermore, in this specification, terms such as "parallel," "orthogonal," and "identical" that specify shapes, geometric conditions, physical characteristics, and the extent thereof, as well as values ​​of lengths, angles, and physical characteristics, are not limited to their strict meanings, but are interpreted to include the range of extent to which similar functions can be expected.

[0042] In addition, in the drawings, for the sake of clarity, the shapes of multiple parts that can be expected to have similar functions are depicted in a regular pattern, but this is not limited to a strict meaning, and the shapes of the parts may differ from each other as long as the function can be expected. In addition, in the drawings, boundary lines indicating the joining surfaces between members are shown as simple straight lines for convenience, but this is not limited to being strictly straight lines, and the shape of the boundary line is arbitrary as long as the desired joining performance can be expected.

[0043] (First embodiment) 1 to 12, a vapor chamber and an electronic device according to a first embodiment of the present disclosure will be described. Vapor chamber 1 according to this embodiment is a device mounted on electronic device E to cool device D (device to be cooled) as a heat-generating body housed in electronic device E. Examples of electronic device E include mobile terminals such as portable terminals and tablet terminals. Examples of device D include electronic devices that generate heat, such as central processing units (CPUs), light-emitting diodes (LEDs), and power semiconductors used in mobile terminals.

[0044] Here, an electronic device E equipped with a vapor chamber 1 according to this embodiment will first be described using a tablet terminal as an example. As shown in FIG. 1, the electronic device E (tablet terminal) includes a housing H, a device D housed in the housing H, and a vapor chamber 1. In the electronic device E shown in FIG. 1, a touch panel display TD is provided on the front surface of the housing H. The vapor chamber 1 is housed in the housing H and arranged so as to be in thermal contact with the device D. This allows the vapor chamber 1 to receive heat generated in the device D when the electronic device E is in use. The heat received by the vapor chamber 1 is released to the outside of the vapor chamber 1 via working fluids 2a and 2b, which will be described later. In this way, the device D is effectively cooled. When the electronic device E is a tablet terminal, the device D corresponds to a central processing unit or the like.

[0045] Next, the vapor chamber 1 according to this embodiment will be described. As shown in Figures 2 and 3, the vapor chamber 1 includes a sealed space 3 in which working fluids 2a and 2b are sealed. The vapor chamber 1 is configured to cool the device D of the electronic device E described above by the working fluids 2a and 2b flowing through the sealed space 3 while repeatedly changing phases. Examples of the working fluids 2a and 2b include pure water, ethanol, methanol, acetone, etc., and mixtures thereof.

[0046] As shown in FIGS. 2 and 3, the vapor chamber 1 includes a lower sheet 10 (second sheet), an upper sheet 20 (first sheet), and a wick sheet 30 (main body sheet) interposed between the lower sheet 10 and the upper sheet 20. In this embodiment, the vapor chamber 1 is composed of the lower sheet 10, the upper sheet 20, and the wick sheet 30. In the vapor chamber 1 according to this embodiment, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are stacked in this order. Note that, in this embodiment, an example is shown in which the wick sheet 30 is composed of one sheet, but the wick sheet 30 may be composed of two or more sheets, and the number of sheets in the wick sheet 30 is arbitrary.

[0047] The vapor chamber 1 is generally formed in the shape of a thin, flat plate. The planar shape of the vapor chamber 1 is arbitrary, and may be a rectangular shape as shown in FIG. 2. The planar shape of the vapor chamber 1 may be, for example, a rectangle with one side of 10 mm to 200 mm and the other side of 50 mm to 600 mm, or a square with one side of 40 mm to 300 mm, and the planar dimensions are arbitrary. In this embodiment, as an example, an example will be described in which the planar shape of the vapor chamber 1 is a rectangular shape with the X direction (first direction) as the longitudinal direction and the Y direction (second direction) perpendicular to the X direction as the lateral direction. In this case, as shown in FIGS. 4 to 6, the lower sheet 10, the upper sheet 20, and the wick sheet 30 may also have the same planar shape as the vapor chamber 1. The planar shape of the vapor chamber 1 is not limited to a rectangular shape and may be any shape, such as a circle, an ellipse, an L-shape, a T-shape, or a U-shape.

[0048] 2, the vapor chamber 1 includes an evaporation region SR where the working fluid 2b evaporates and a condensation region CR where the working vapor 2a condenses. Here, the working vapor 2a is a working fluid in a gaseous state, i.e., a vapor of the working fluid, and the working fluid 2b is a working fluid in a liquid state, i.e., a liquid of the working fluid.

[0049] The evaporation region SR is the region that overlaps with the device D in a planar view and is the region where the device D is attached. The evaporation region SR can be located at any position on the vapor chamber 1. In the illustrated example, the evaporation region SR is formed on the negative side of the vapor chamber 1 in the X direction (the left side in FIG. 2). Heat from the device D is transferred to the evaporation region SR, and this heat evaporates the working fluid 2b, generating working vapor 2a. The heat from the device D can be transferred not only to the region that overlaps with the device D in a planar view, but also to the surrounding area of ​​that region. Therefore, the evaporation region SR includes the region that overlaps with the device D in a planar view and the surrounding area.

[0050] Here, the plan view refers to the state when the vapor chamber 1 is viewed from a direction perpendicular to the surface that receives heat from the device D and the surface that releases the received heat. In this embodiment, the surface that receives heat corresponds to the upper sheet outer surface 20b of the upper sheet 20, which will be described later, and the surface that releases heat corresponds to the lower sheet outer surface 10a of the lower sheet 10, which will be described later. Note that the surface that receives heat may correspond to the lower sheet outer surface 10a, and the surface that releases heat may correspond to the upper sheet outer surface 20b. For example, as shown in FIG. 2, the state when the vapor chamber 1 is viewed from above or below corresponds to the plan view.

[0051] The condensation region CR is a region that does not overlap with the device D in a plan view, and is a region where the working vapor 2a mainly releases heat and condenses. The condensation region CR can also be said to be a region surrounding the evaporation region SR. In the illustrated example, the condensation region CR is formed on the positive side of the vapor chamber 1 in the X direction (the right side in FIG. 2). In the condensation region CR, heat from the working vapor 2a is released to the lower sheet 10, and the working vapor 2a is cooled and condensed, producing working liquid 2b.

[0052] When the vapor chamber 1 is installed inside a mobile terminal, the up-down relationship may be lost depending on the orientation of the mobile terminal. However, in this embodiment, for convenience, the sheet that receives heat from the device D will be referred to as the upper sheet 20, and the sheet that releases the received heat will be referred to as the lower sheet 10. For this reason, the following description will be given assuming that the lower sheet 10 is positioned on the lower side and the upper sheet 20 is positioned on the upper side.

[0053] As shown in Fig. 3, the lower sheet 10 includes a lower sheet outer surface 10a (second sheet outer surface) provided on the side opposite the wick sheet 30, and a lower sheet inner surface 10b (second sheet inner surface) facing the wick sheet 30. A housing member Ha that forms part of a housing H of a mobile terminal or the like is attached to this lower sheet outer surface 10a. The entire lower sheet outer surface 10a may be covered with the housing member Ha. The lower sheet 10 may be formed to be generally flat, or may have a uniform thickness overall.

[0054] As shown in Fig. 4, alignment holes 12 may be provided at the four corners of the lower sheet 10. In the example shown in Fig. 4, the planar shape of the alignment holes 12 is circular, but this is not limited to this. The alignment holes 12 may also penetrate the lower sheet 10.

[0055] As shown in Fig. 3, the upper sheet 20 includes an upper sheet inner surface 20a (first sheet inner surface) facing the wick sheet 30, and an upper sheet outer surface 20b (first sheet outer surface) provided on the opposite side of the upper sheet inner surface 20a. The device D described above is attached to this upper sheet outer surface 20b. Furthermore, as shown in Figs. 3 and 5, the upper sheet 20 includes an upper sheet groove 70 (first sheet groove) provided in the upper sheet inner surface 20a. The upper sheet groove 70 will be described in detail later.

[0056] As shown in Fig. 5, alignment holes 22 may be provided at the four corners of the upper sheet 20. In the example shown in Fig. 5, the planar shape of the alignment holes 22 is circular, but this is not limited to this. The alignment holes 22 may also penetrate the upper sheet 20.

[0057] 3, the wick sheet 30 includes a wick sheet lower surface 30a (second main body surface) and a wick sheet upper surface 30b (first main body surface) provided on the opposite side of the wick sheet lower surface 30a. The wick sheet lower surface 30a faces the lower sheet inner surface 10b of the lower sheet 10. The wick sheet upper surface 30b faces the upper sheet inner surface 20a of the upper sheet 20.

[0058] The lower sheet inner surface 10b and the wick sheet lower surface 30a may be permanently bonded to each other by thermocompression bonding. Similarly, the upper sheet inner surface 20a and the wick sheet upper surface 30b may be permanently bonded to each other by thermocompression bonding. An example of bonding by thermocompression bonding is diffusion bonding. However, the lower sheet 10, the upper sheet 20, and the wick sheet 30 may be bonded by other methods such as brazing instead of diffusion bonding.

[0059] The term "permanently joined" is not limited to a strict meaning, but is used to mean that the joining is sufficient to maintain the sealing of the sealed space 3 when the vapor chamber 1 is in operation.

[0060] 2 and 6, the wick sheet 30 includes a frame body portion 32 and a plurality of land portions 33 provided within the frame body portion 32. The frame body portion 32 and the land portions 33 are portions that are not etched in the etching step described below, and the material of the wick sheet 30 remains.

[0061] In the illustrated example, the frame portion 32 is formed in a rectangular frame shape in a plan view. A steam flow path portion 50 is provided inside the frame portion 32. The steam flow path portion 50 accommodates the working fluids 2a and 2b. Each land portion 33 is provided inside the frame portion 32, and the steam flow path portion 50 is provided around each land portion 33. Therefore, the working steam 2a flows around each land portion 33.

[0062] In the illustrated example, each land portion 33 extends in the X direction (the left-right direction in FIG. 6) in a plan view, and the planar shape of each land portion 33 is an elongated rectangle. The lands 33 are also aligned along the Y direction (the up-down direction in FIG. 6) perpendicular to the X direction. The lands 33 may be aligned at regular intervals in the Y direction. The width w1 of each land portion 33 (see FIG. 7) may be, for example, 100 μm to 3000 μm. Here, the width w1 of the land portion 33 is the dimension of the land portion 33 in the Y direction, and refers to the dimension in the Z direction at a position where a through portion 34, which will be described later, is present.

[0063] Here, the X direction is specified as the direction in which second steam passages 52 of the steam flow path section 50, which will be described later, extend. The Y direction is specified as the direction perpendicular to the X direction in a plan view. The Z direction is specified as the direction perpendicular to the X direction and the Y direction, and corresponds to the thickness direction of the wick sheet 30.

[0064] The frame body 32 and each land portion 33 are diffusion bonded to the lower sheet 10 and also to the upper sheet 20. This improves the mechanical strength of the vapor chamber 1. Wall surfaces 53a of the lower vapor flow path recess 53 and wall surfaces 54a of the upper vapor flow path recess 54 (described later) form the side walls of the land portion 33. The wick sheet lower surface 30a and the wick sheet upper surface 30b may be formed flat across the frame body 32 and each land portion 33.

[0065] As shown in Fig. 6, alignment holes 35 may be provided at the four corners of the wick sheet 30. In the example shown in Fig. 6, the planar shape of the alignment holes 35 is circular, but this is not limited to this. The alignment holes 35 may penetrate the wick sheet 30.

[0066] The wick sheet 30 also includes a vapor flow path portion 50 through which the working vapor 2a passes, and a liquid flow path portion 60 that communicates with the vapor flow path portion 50 and through which the working liquid 2b passes.

[0067] The vapor flow path section 50 is a flow path through which the working vapor 2a mainly passes. The working liquid 2b may also pass through the vapor flow path section 50. As shown in FIGS. 3 and 7, the vapor flow path section 50 may extend from the wick sheet lower surface 30a to the wick sheet upper surface 30b and penetrate the wick sheet 30. The vapor flow path section 50 may be covered by the lower sheet 10 at the wick sheet lower surface 30a, or may be covered by the upper sheet 20 at the wick sheet upper surface 30b.

[0068] As shown in FIG. 6, the steam flow path section 50 may include a first steam passage 51 and a plurality of second steam passages 52. The first steam passage 51 is formed between the frame body section 32 and the land section 33. The first steam passage 51 is formed inside the frame body section 32 and continuously outside the land section 33. The first steam passage 51 has a planar shape of a rectangular frame. The second steam passage 52 is formed between adjacent land sections 33. The second steam passage 52 extends along the X direction. The planar shape of the second steam passage 52 is an elongated rectangular shape. The plurality of lands 33 divide the steam flow path portion 50 into a first steam passage 51 and a plurality of second steam passages 52 .

[0069] In the present embodiment, the steam flow path section 50 includes the first steam passage 51, but the steam flow path section 50 does not necessarily have to include the first steam passage 51. In other words, the frame body section 32 and the land section 33 may be disposed adjacent to each other, and no steam passage may be provided between the frame body section 32 and the land section 33.

[0070] 3 and 7, the first vapor passage 51 and the second vapor passage 52 may extend from the wick sheet lower surface 30a to the wick sheet upper surface 30b and penetrate the wick sheet 30. The first vapor passage 51 and the second vapor passage 52 include a lower vapor flow path recess 53 provided in the wick sheet lower surface 30a and an upper vapor flow path recess 54 provided in the wick sheet upper surface 30b. The lower vapor flow path recess 53 and the upper vapor flow path recess 54 are connected to each other, and the first vapor passage 51 and the second vapor passage 52 are formed to extend from the wick sheet lower surface 30a to the wick sheet upper surface 30b.

[0071] The lower steam flow path recess 53 is formed in a concave shape on the wick sheet lower surface 30a by etching the wick sheet 30 from the wick sheet lower surface 30a in an etching process described below. Here, "concave" on the wick sheet lower surface 30a means that the recess is formed so as to be recessed from the wick sheet lower surface 30a. As a result, the lower steam flow path recess 53 has a curved wall surface 53a, as shown in FIG. 7. This wall surface 53a defines the lower steam flow path recess 53, and in the cross section shown in FIG. 7, it curves so as to approach the opposing wall surface 53a as it extends toward the wick sheet upper surface 30b. As shown in FIGS. 3 and 7, the working fluid 2b can adhere to this wall surface 53a. This lower steam flow path recess 53 constitutes a portion (lower half) of the first steam passage 51 and a portion (lower half) of the second steam passage 52.

[0072] The upper steam flow path recess 54 is formed in a concave shape on the wick sheet upper surface 30b by etching the wick sheet 30 from the wick sheet upper surface 30b in an etching process described below. Here, "concave" on the wick sheet upper surface 30b means that the recess is formed so as to be recessed from the wick sheet upper surface 30b. As a result, the upper steam flow path recess 54 has a curved wall surface 54a, as shown in FIG. 7. This wall surface 54a defines the upper steam flow path recess 54, and in the cross section shown in FIG. 7, it curves so as to approach the opposing wall surface 54a as it extends toward the wick sheet lower surface 30a. As shown in FIGS. 3 and 7, the working fluid 2b can adhere to this wall surface 54a. This upper steam flow path recess 54 constitutes a portion (upper half) of the first steam passage 51 and a portion (upper half) of the second steam passage 52.

[0073] As shown in FIG. 7 , the wall surface 53a of the lower steam flow path recess 53 and the wall surface 54a of the upper steam flow path recess 54 are connected to form the through-portion 34. In the illustrated example, the planar shape of the through-portion 34 in the first steam passage 51 is a rectangular frame like the first steam passage 51, and the planar shape of the through-portion 34 in the second steam passage 52 is an elongated rectangular like the second steam passage 52. The through-portion 34 may be defined by a ridge line formed by the joining of the wall surface 53a of the lower steam flow path recess 53 and the wall surface 54a of the upper steam flow path recess 54, which juts out inward. In this through-portion 34, the planar area of ​​the first steam passage 51 may be the smallest, or the planar area of ​​the second steam passage 52 may be the smallest. The width w2 (see FIG. 7 ) of the through-portion 34 of each steam passage 51, 52 may be, for example, 400 μm to 1600 μm. Here, the width w2 of the through portion 34 of the first steam passage 51 corresponds to the gap between adjacent land portions 33 in the Y direction. Moreover, the width w2 of the through portion 34 of the second steam passage 52 corresponds to the gap between the frame portion 32 and the land portion 33 in the Y direction (or X direction).

[0074] The position of the through-hole 34 in the Z direction (the vertical direction in FIG. 7) may be an intermediate position between the lower surface 30a of the wick sheet and the upper surface 30b of the wick sheet. However, this is not limited thereto, and the through-hole 34 may be located closer to the lower sheet 10 than the intermediate position, or closer to the upper sheet 20 than the intermediate position. The position of the through-hole 34 in the Z direction is arbitrary.

[0075] In the illustrated example, as described above, the cross-sectional shapes of the first steam passage 51 and the second steam passage 52 are formed to include the through-holes 34 defined by ridges formed to protrude inward, but this is not limitative. For example, the cross-sectional shapes of the first steam passage 51 and the second steam passage 52 may be trapezoidal, rectangular, or barrel-shaped.

[0076] The steam flow path section 50 including the first steam path 51 and the second steam path 52 configured in this manner constitutes part of the above-mentioned sealed space 3. As shown in Fig. 3, the first steam path 51 and the second steam path 52 are defined mainly by the lower sheet 10, the upper sheet 20, and the frame portion 32 and land portion 33 of the above-mentioned wick sheet 30. Each of the steam paths 51, 52 has a relatively large flow path cross-sectional area to allow the working steam 2a to pass through.

[0077] Here, in order to clarify the drawing, Figure 3 shows the first steam passage 51 and the second steam passage 52, etc. in an enlarged scale, and the number and arrangement of these steam passages 51, 52, etc. are different from those in Figures 2, 6 to 10, etc.

[0078] Although not shown, the steam flow path section 50 may be provided with a plurality of support portions that support the land portions 33 on the frame portion 32. Furthermore, a plurality of connecting portions 38 (see FIGS. 37 and 38) that connect adjacent land portions 33 may be provided. The support portions and connecting portions 38 may be formed so as not to impede the flow of the working steam 2a diffusing through the steam flow path section 50. For example, the support portions and connecting portions 38 may be disposed near one of the wick sheet lower surface 30a and the wick sheet upper surface 30b of the wick sheet 30, and a space forming a steam flow path recess may be formed near the other. This allows the thickness of the support portions and connecting portions 38 to be thinner than the thickness of the wick sheet 30, preventing the first steam path 51 and the second steam path 52 from being separated in the X and Y directions.

[0079] The liquid flow path section 60 is a flow path through which the working liquid 2b mainly passes. The working vapor 2a may also pass through the liquid flow path section 60. As shown in FIGS. 3, 6, and 7, the liquid flow path section 60 may be provided on the wick sheet upper surface 30b of the wick sheet 30. In the illustrated example, the liquid flow path section 60 is provided on the wick sheet upper surface 30b in each land section 33. The liquid flow path section 60 constitutes a part of the sealed space 3 and is connected to the vapor flow path section 50. The liquid flow path section 60 is configured as a capillary structure (wick) for transporting the working liquid 2b to the evaporation region SR. The liquid flow path section 60 may be formed over the entire wick sheet upper surface 30b in each land section 33. The liquid flow path section 60 may also be provided on the wick sheet upper surface 30b in the frame section 32.

[0080] 8, the liquid flow path section 60 may be composed of a plurality of grooves provided on the upper surface 30b of the wick sheet. More specifically, the liquid flow path section 60 may include a plurality of liquid flow path main grooves 61 through which the working fluid 2b passes, and a plurality of liquid flow path communication grooves 65 that communicate with the liquid flow path main grooves 61.

[0081] As shown in FIG. 8, each liquid flow path mainstream groove 61 extends along the X direction. Each liquid flow path mainstream groove 61 has a small flow path cross-sectional area so that the working fluid 2b flows mainly by capillary action. The flow path cross-sectional area of ​​each liquid flow path mainstream groove 61 is smaller than the flow path cross-sectional area of ​​each vapor passage 51, 52. Each liquid flow path mainstream groove 61 is configured to transport the working fluid 2b condensed from the working vapor 2a to the evaporation region SR. Each liquid flow path mainstream groove 61 may be aligned along the Y direction. The liquid flow path main grooves 61 may be arranged parallel to one another at regular intervals.

[0082] The liquid flow path main grooves 61 may be formed by etching the wick sheet 30 from the wick sheet upper surface 30b in an etching step described below. As a result, the liquid flow path main grooves 61 may have curved wall surfaces 62, as shown in Fig. 7. These wall surfaces 62 define the liquid flow path main grooves 61, and may be curved concavely toward the wick sheet lower surface 30a.

[0083] The width w3 (dimension in the Y direction) of the liquid flow path mainstream groove 61 shown in Figures 7 and 8 is smaller than the width w2 of the through portions 34 of the vapor passages 51, 52 and smaller than the width w1 of the land portions 33. The width w3 of the liquid flow path mainstream groove 61 may be, for example, 5 µm to 150 µm. Here, the width w3 of the liquid flow path mainstream groove 61 refers to the dimension on the wick sheet upper surface 30b. Furthermore, the depth h1 (dimension in the Z direction) of the liquid flow path mainstream groove 61 shown in Figure 7 may be, for example, 3 µm to 150 µm.

[0084] 8, each liquid flow path communication groove 65 extends in a direction intersecting the X direction. In the illustrated example, each liquid flow path communication groove 65 extends in the Y direction and is formed perpendicular to the liquid flow path mainstream grooves 61. Some liquid flow path communication grooves 65 connect adjacent liquid flow path mainstream grooves 61. Other liquid flow path communication grooves 65 connect the first vapor passage 51 or the second vapor passage 52 to the liquid flow path mainstream groove 61. In other words, the liquid flow path communication groove 65 extends from the edge of the land portion 33 in the Y direction to the liquid flow path mainstream groove 61 adjacent to that edge. In this way, the first vapor passage 51 and the liquid flow path mainstream groove 61 are connected, and the second vapor passage 52 and the liquid flow path mainstream groove 61 are connected.

[0085] The liquid flow path communication grooves 65 have a small flow path cross-sectional area so that the working fluid 2b flows mainly by capillary action. The flow path cross-sectional area of ​​the liquid flow path communication grooves 65 is smaller than the flow path cross-sectional area of ​​the vapor passages 51, 52. The liquid flow path communication grooves 65 may be aligned along the X direction. The liquid flow path communication grooves 65 may also be aligned parallel to one another at regular intervals.

[0086] The liquid flow path connecting groove 65 may also be formed by etching, similar to the liquid flow path mainstream groove 61. As a result, the liquid flow path connecting groove 65 may have wall surfaces (not shown) formed in a curved shape similar to the liquid flow path mainstream groove 61. The width w4 (dimension in the X direction) of the liquid flow path connecting groove 65 shown in FIG. 8 is smaller than the width w2 of the through-portions 34 of the steam passages 51, 52 and smaller than the width w1 of the land portions 33. The width w4 of the liquid flow path connecting groove 65 may be equal to the width w3 of the liquid flow path mainstream groove 61. However, this is not a limitation, and the width w4 of the liquid flow path connecting groove 65 may be larger or smaller than the width w3 of the liquid flow path mainstream groove 61. The depth of the liquid flow path connecting groove 65 may be equal to the depth h1 of the liquid flow path mainstream groove 61. However, this is not a limitation, and the depth of the liquid flow path connecting groove 65 may be larger or smaller than the depth h1 of the liquid flow path mainstream groove 61.

[0087] As shown in FIG. 8, the liquid flow path section 60 may have a liquid flow path convex row 63 provided on the wick sheet upper surface 30b. The liquid flow path convex row 63 is provided between adjacent liquid flow path main grooves 61. Each liquid flow path convex row 63 includes a plurality of liquid flow path convex sections 64 aligned in the X direction. The liquid flow path convex sections 64 abut against the upper sheet inner surface 20a. Each liquid flow path convex section 64 is formed in a rectangular shape with the X direction as its longitudinal direction in plan view. A liquid flow path main groove 61 is interposed between adjacent liquid flow path convex sections 64 in the Y direction. A liquid flow path connecting groove 65 is interposed between adjacent liquid flow path convex sections 64 in the X direction.

[0088] The liquid flow path convex portion 64 is a portion that is not etched in the etching step described below, and remains as the material of the wick sheet 30. As shown in Fig. 8, the planar shape of the liquid flow path convex portion 64 (the shape at the position of the wick sheet upper surface 30b) may be rectangular.

[0089] As shown in FIG. 8, the liquid flow path convex portions 64 may be arranged in a staggered pattern. More specifically, the liquid flow path convex portions 64 of liquid flow path convex portion rows 63 adjacent to each other in the Y direction may be arranged so as to be offset from each other in the X direction. This offset amount may be half the arrangement pitch of the liquid flow path convex portions 64 in the X direction. The width w5 (dimension in the Y direction) of the liquid flow path convex portions 64 shown in FIG. 8 may be, for example, 5 μm to 500 μm. Here, the width w5 of the liquid flow path convex portion 64 refers to the dimension on the wick sheet upper surface 30b. The width w5 of the liquid flow path convex portion 64 corresponds to the gap between the liquid flow path main grooves 61 adjacent to each other in the Y direction. The arrangement of the liquid flow path convex portions 64 is not limited to a staggered pattern and may be arranged in parallel. In this case, the liquid flow path convex portions 64 of the liquid flow path convex portion rows 63 adjacent to each other in the Y direction are also aligned in the X direction.

[0090] 2, the vapor chamber 1 may also include an injection part 4 for injecting the working liquid 2b into the sealed space 3. The position of the injection part 4 is arbitrary, but as shown in FIG. 2, the injection part 4 may be provided on the edge of the vapor chamber 1 on the negative side in the X direction (the left side in FIG. 2). The injection part 4 may have an injection flow path 37 formed in the wick sheet 30. After the working liquid 2b is injected, the injection flow path 37 may be sealed.

[0091] The materials constituting the lower sheet 10, the upper sheet 20, and the wick sheet 30 are not particularly limited as long as they have good thermal conductivity. The lower sheet 10, the upper sheet 20, and the wick sheet 30 may contain, for example, copper or a copper alloy. In this case, the thermal conductivity of each sheet 10, 20, and 30 can be increased, thereby improving the heat dissipation efficiency of the vapor chamber 1. Furthermore, when pure water is used as the working fluids 2a and 2b, corrosion can be prevented. However, other metal materials such as aluminum or titanium, or other metal alloy materials such as stainless steel, may be used for these sheets 10, 20, and 30 as long as the desired heat dissipation efficiency can be achieved and corrosion can be prevented.

[0092] 3 may be, for example, 100 μm to 1000 μm. By making the thickness t1 of the vapor chamber 1 100 μm or more, the vapor channel section 50 can be properly secured, allowing the vapor chamber 1 to function properly. On the other hand, by making the thickness t1 1000 μm or less, the vapor chamber 1 can be prevented from becoming too thick.

[0093] The thickness t2 of the lower sheet 10 shown in FIG. 3 may be, for example, 6 μm to 100 μm. By setting the thickness t2 of the lower sheet 10 to 6 μm or more, the mechanical strength of the lower sheet 10 can be ensured. On the other hand, by setting the thickness t2 of the lower sheet 10 to 100 μm or less, an increase in the thickness of the vapor chamber 1 can be prevented. Similarly, the thickness t3 of the upper sheet 20 shown in FIG. 3 may be set to be the same as the thickness t2 of the lower sheet 10. The thickness t3 of the upper sheet 20 and the thickness t2 of the lower sheet 10 may be different from each other.

[0094] 3 may be, for example, 50 μm to 400 μm. By making the thickness t4 of the wick sheet 30 50 μm or more, the vapor flow path portion 50 can be properly secured, and the vapor chamber 1 can function properly. On the other hand, by setting the thickness to 400 μm or less, the vapor chamber 1 can be prevented from becoming thicker.

[0095] As described above, the upper sheet 20 of the vapor chamber 1 according to this embodiment includes the upper sheet groove 70 provided in the upper sheet inner surface 20a. As shown in Figures 5, 9, and 10, the upper sheet 20 may include multiple upper sheet grooves 70.

[0096] FIG. 10 is a partially enlarged top view showing the wick sheet 30 and the upper sheet 20 overlapped with each other. As shown in FIG. 10 , the upper sheet groove 70 is provided at a position overlapping with the steam passages 51 and 52 in a plan view. In the illustrated example, the upper sheet groove 70 is provided at a position overlapping with the second steam passage 52 in a plan view, and the entire upper sheet groove 70 overlaps with the second steam passage 52 in a plan view. It can also be said that the upper sheet groove 70 is provided between adjacent land portions 33 in a plan view. The upper sheet groove 70 may be provided at a position overlapping with the first steam passage 51 in a plan view. In this case, the upper sheet groove 70 may be provided at a position overlapping with a portion of the first steam passage 51 extending in the X direction in a plan view.

[0097] As shown in FIGS. 9 and 10 , the upper sheet groove 70 extends in a direction intersecting the X direction. In the illustrated example, the upper sheet groove 70 extends in the Y direction, which is perpendicular to the X direction. The planar shape of the upper sheet groove 70 is an elongated rectangle. The upper sheet groove 70 includes a first end 71 and a second end 72 provided at both ends in the Y direction. The first end 71 constitutes the end of the upper sheet groove 70 on the positive side in the Y direction (the upper side in FIGS. 9 and 10 ), and the second end 72 constitutes the end of the upper sheet groove 70 on the negative side in the Y direction (the lower side in FIGS. 9 and 10 ). In the illustrated example, both the first end 71 and the second end 72 are provided at positions overlapping with the second steam passage 52 in a plan view.

[0098] 9 and 10, the upper sheet grooves 70 may be aligned along the X direction. The upper sheet grooves 70 may be aligned parallel to one another at regular intervals.

[0099] The upper sheet groove 70 may be formed by etching the upper sheet 20 from the upper sheet inner surface 20a. As a result, the upper sheet groove 70 may have a curved wall surface 73, as shown in FIG. 11. The wall surface 73 defines the upper sheet groove 70 and may be concavely curved from the upper sheet inner surface 20a toward the upper sheet outer surface 20b. In the example shown in FIG. 11, the cross-sectional shape of the upper sheet groove 70 is semicircular.

[0100] The upper sheet groove 70 has a small cross-sectional area so that the working fluid 2b flows mainly by capillary action. The upper sheet groove 70 has a cross-sectional area smaller than the cross-sectional area of ​​the vapor passages 51 and 52. The upper sheet groove 70 promotes the movement of the working fluid 2b between the steam passages 51 and 52 and the liquid passage section 60. The cross-sectional area of ​​the upper sheet groove 70 may be equal to the cross-sectional area of ​​the main liquid passage groove 61. However, this is not limited thereto, and the cross-sectional area of ​​the upper sheet groove 70 may be smaller than the cross-sectional area of ​​the main liquid passage groove 61. In this case, the capillary action of the upper sheet groove 70 applies a driving force to the working fluid 2b from the liquid passage section 60 toward the upper sheet groove 70, allowing the working fluid 2b in the liquid passage section 60 to quickly move through the upper sheet groove 70 to the steam passages 51 and 52. The cross-sectional area of ​​the upper sheet groove 70 may be larger than the cross-sectional area of ​​the main liquid flow path groove 61. In this case, the capillary action of the upper sheet groove 70 applies a driving force to the working fluid 2b from the upper sheet groove 70 toward the liquid flow path section 60, and the working fluid 2b in the vapor passages 51, 52 can be quickly moved to the liquid flow path section 60 through the upper sheet groove 70.

[0101] The length L1 (dimension in the Y direction) of the upper sheet groove 70 shown in Fig. 9 may be larger than the width w3 (see Fig. 7) of the liquid flow path mainstream groove 61, and may also be larger than the width w5 (see Fig. 8) of the liquid flow path convex portion 64. If the upper sheet groove 70 has a flow path cross-sectional area smaller than the flow path cross-sectional area of ​​the steam passages 51, 52, the length L1 of the upper sheet groove 70 may be larger than the width w6 of the upper sheet groove 70, which will be described later. The length L1 of the upper sheet groove 70 may be larger than 5 µm, for example.

[0102] 9 and 11 may be equal to the width w3 (see FIG. 7) of the liquid flow path mainstream groove 61. However, this is not limiting, and the width w6 of the upper sheet groove 70 may be smaller or larger than the width w3 of the liquid flow path mainstream groove 61. The width w6 of the upper sheet groove 70 (dimension in the X direction) may be, for example, 5 μm to 150 μm. Here, the width w6 of the upper sheet groove 70 refers to the dimension at the upper sheet inner surface 20a.

[0103] The depth h2 (dimension in the Z direction) of the upper sheet groove 70 shown in Fig. 11 may be equal to the depth h1 (see Fig. 7) of the liquid flow path mainstream groove 61. However, this is not limited thereto, and the depth h2 of the upper sheet groove 70 may be deeper or shallower than the depth h1 of the liquid flow path mainstream groove 61. The depth h2 of the upper sheet groove 70 may be, for example, 3 µm to 150 µm.

[0104] The gap w7 between adjacent upper sheet grooves 70 in the X direction shown in FIG. 11 may be equal to the gap between adjacent main liquid flow path grooves 61 in the Y direction, i.e., the width w5 of the liquid flow path convex portion 64 (see FIG. 8), or may be smaller than the width w5 of the liquid flow path convex portion 64. In this case, more upper sheet grooves 70 can be arranged, allowing a sufficient amount of working fluid 2b to circulate between the vapor passages 51, 52 and the liquid flow path portion 60. However, this is not limited thereto, and the gap w7 between adjacent upper sheet grooves 70 in the X direction may be larger than the width w5 of the liquid flow path convex portion 64. The gap w7 between adjacent upper sheet grooves 70 in the X direction may be, for example, 3 μm to 500 μm.

[0105] In this embodiment, the planar shape of the upper seat groove 70 is an elongated rectangular shape, and the cross-sectional shape of the upper seat groove 70 is semicircular, but this is not limited to this, and the shape of the upper seat groove 70 is arbitrary.

[0106] In addition, in the present embodiment, the upper sheet groove 70 is provided over the entire area overlapping with the second steam passage 52 in a plan view, but this is not limited thereto, and the upper sheet groove 70 may be provided only in a part of the area overlapping with the steam passages 51, 52 in a plan view. For example, the upper sheet groove 70 may be disposed only in the evaporation region SR. Also, for example, the upper seat groove 70 may be disposed only in the condensation region CR.

[0107] Next, a method for manufacturing the vapor chamber 1 having such a configuration will be described.

[0108] First, in the sheet preparation process, the sheets 10, 20, and 30 are prepared. The sheet preparation process includes a lower sheet preparation process for preparing the lower sheet 10, an upper sheet preparation process for preparing the upper sheet 20, and a wick sheet preparation process for preparing the wick sheet 30.

[0109] In the lower sheet preparation step, first, a lower sheet base material having a desired thickness is prepared. The lower sheet base material may be a rolled material. Next, the lower sheet base material is etched to form the lower sheet 10 having a desired planar shape. Alternatively, the lower sheet base material may be press-formed to form the lower sheet 10 having a desired planar shape. In this manner, the lower sheet 10 as shown in FIG. 4 can be prepared.

[0110] In the upper sheet preparation process, as in the lower sheet preparation process, first, an upper sheet base material having a desired thickness is prepared. The upper sheet base material may be a rolled material. Next, the upper sheet base material is etched to form the upper sheet 20 having a desired planar shape. This etching forms the upper sheet grooves 70 described above in the upper sheet 20. Alternatively, the upper sheet 20 having the desired planar shape may be formed by pressing the upper sheet base material. Alternatively, the upper sheet grooves 70 may be formed by cutting the upper sheet base material. In this manner, the upper sheet 20 as shown in FIG. 5 can be prepared.

[0111] The wick sheet preparation process may include a material sheet preparation process for preparing a metal material sheet and an etching process for etching the metal material sheet. First, in the material sheet preparation process, a flat metal material sheet having a desired thickness is prepared. The metal material sheet may be a rolled material. Next, in the etching process, the metal material sheet is etched from the first material surface and the second material surface to form a wick sheet 30 having a desired planar shape and having a vapor flow path portion 50 and a liquid flow path portion 60. In this manner, a wick sheet 30 as shown in FIG. 6 can be prepared.

[0112] Here, in the etching step, the first material surface and the second material surface of the metal material sheet may be etched simultaneously. However, this is not limited thereto, and the etching of the first material surface and the second material surface may be performed in separate steps. Furthermore, the vapor flow path section 50 and the liquid flow path section 60 may be formed by simultaneous etching, or may be formed by etching in separate steps. For example, an iron chloride-based etching solution such as a ferric chloride aqueous solution, or a copper chloride-based etching solution such as a copper chloride aqueous solution may be used as the etching solution.

[0113] After the sheet preparation process, the lower sheet 10, the upper sheet 20, and the wick sheet 30 are joined together in the joining process. First, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are stacked in this order. At this time, the sheets 10, 20, and 30 may be aligned using the alignment holes 12 in the lower sheet 10, the alignment holes 35 in the wick sheet 30, and the alignment holes 22 in the upper sheet 20. Next, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are temporarily joined together. For example, the sheets 10, 20, and 30 may be temporarily joined together by spot welding or laser welding. Next, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are permanently joined together by thermocompression bonding. For example, the sheets 10, 20, and 30 may be joined together by diffusion bonding.

[0114] After the joining step, the hydraulic fluid 2b is injected into the sealed space 3 from the injection flow path 37 of the injection section 4 as an injection step.

[0115] After the injection step, the injection flow path 37 is sealed in the sealing step. This blocks communication between the sealed space 3 and the outside, sealing the sealed space 3. This makes it possible to obtain the sealed space 3 filled with the working fluid 2b, and to prevent the working fluid 2b in the sealed space 3 from leaking to the outside.

[0116] In this manner, the vapor chamber 1 according to this embodiment can be obtained.

[0117] Next, the method of operating the vapor chamber 1, that is, the method of cooling the device D, will be described.

[0118] The vapor chamber 1 obtained as described above is installed in a housing H of a mobile terminal or the like. Then, a device D, such as a CPU, which is an apparatus to be cooled, is attached to the upper sheet outer surface 20b of the upper sheet 20 (or the vapor chamber 1 is attached to the device D). The working fluid 2b in the sealed space 3 adheres due to its surface tension to the wall surfaces of the sealed space 3, namely, the wall surface 53a of the lower vapor flow path recess 53, the wall surface 54a of the upper vapor flow path recess 54, the wall surface 62 of the liquid flow path main groove 61 of the liquid flow path section 60, and the wall surface of the liquid flow path connecting groove 65. The working fluid 2b may also adhere to the portions of the lower sheet inner surface 10b of the lower sheet 10 that are exposed to the lower steam flow path recess 53. Furthermore, the working fluid 2b may also adhere to the portions of the upper sheet inner surface 20a of the upper sheet 20 that are exposed to the upper steam flow path recess 54, the liquid flow path main groove 61, and the liquid flow path connecting groove 65.

[0119] In this state, when device D generates heat, working fluid 2b present in evaporation region SR (see FIG. 6) receives heat from device D. The received heat is absorbed as latent heat, causing working fluid 2b to evaporate (vaporize), generating working vapor 2a. The generated working vapor 2a diffuses within first vapor passage 51 and second vapor passage 52 that form sealed space 3. More specifically, working vapor 2a diffuses in the X direction mainly in the portion of first vapor passage 51 that extends in the X direction and in second vapor passage 52 (see solid arrows in FIG. 6).

[0120] Then, the working steam 2a in each steam passage 51, 52 leaves the evaporation region SR and is transported to the condensation region CR (the right part in FIG. 6) where the temperature is relatively low. In the condensation region CR, the working steam 2a is cooled by radiating heat mainly to the lower sheet 10. The heat received by the lower sheet 10 from the working steam 2a is transferred to the outside air via the housing member Ha (see FIG. 3).

[0121] The working vapor 2a dissipates heat to the lower sheet 10 in the condensation region CR, thereby losing the latent heat absorbed in the evaporation region SR. This causes the working vapor 2a to condense, generating working liquid 2b. The generated working liquid 2b adheres to the wall surfaces 53a, 54a of the vapor flow path recesses 53, 54, the lower sheet inner surface 10b of the lower sheet 10, and the upper sheet inner surface 20a of the upper sheet 20. Here, the working liquid 2b continues to evaporate in the evaporation region SR. Therefore, the working liquid 2b present in the liquid flow path section 60 in regions other than the evaporation region SR (i.e., the condensation region CR) is transported toward the evaporation region SR by the capillary action of the liquid flow path mainstream grooves 61 (see the dashed arrows in FIG. 6). As a result, the working liquid 2b adhering to the wall surfaces 53a, 54a, the lower sheet inner surface 10b, and the upper sheet inner surface 20a moves to the liquid flow path section 60, passes through the liquid flow path connecting grooves 65, and enters the liquid flow path mainstream grooves 61. In this way, the working fluid 2b is filled into each liquid flow path mainstream groove 61 and each liquid flow path connecting groove 65. The filled working fluid 2b obtains a driving force toward the evaporation region SR due to the capillary action of each liquid flow path mainstream groove 61, and is smoothly transported toward the evaporation region SR.

[0122] In the liquid flow path section 60, each liquid flow path mainstream groove 61 communicates with the adjacent other liquid flow path mainstream groove 61 via the corresponding liquid flow path connection groove 65. This allows the working fluid 2b to move back and forth between the adjacent liquid flow path mainstream grooves 61, and prevents the occurrence of dryout in the liquid flow path mainstream grooves 61. As a result, capillary action is imparted to the working fluid 2b in each liquid flow path mainstream groove 61, and the working fluid 2b is transported smoothly toward the evaporation region SR.

[0123] The working fluid 2b that has reached the evaporation region SR is again heated by the device D and evaporates. The working vapor 2a that has evaporated from the working fluid 2b passes through the liquid flow path connecting groove 65 in the evaporation region SR and moves to the lower vapor flow path recess 53 and the upper vapor flow path recess 54, which have large flow path cross-sectional areas. The working vapor 2a then diffuses within each of the vapor flow path recesses 53 and 54. In this way, the working fluids 2a and 2b circulate within the sealed space 3 while repeatedly undergoing phase changes, i.e., evaporation and condensation. This diffuses and releases the heat from the device D. As a result, the device D is cooled.

[0124] In this embodiment, an upper sheet groove 70 is provided on the upper sheet inner surface 20a of the upper sheet 20. The upper sheet groove 70 is provided at a position overlapping the vapor passages 51 and 52 in a plan view and extends along a direction intersecting the X direction. As a result, in the condensation region CR, the working fluid 2b can smoothly move from the vapor passages 51 and 52 to the liquid flow path portion 60 through the upper sheet groove 70 and smoothly enter the liquid flow path mainstream groove 61. Furthermore, in the evaporation region SR, the working fluid 2b can move from the liquid flow path portion 60 to the vapor passages 51 and 52 through the upper sheet groove 70. Therefore, the working fluid 2b that has moved to the vapor passages 51 and 52 can effectively absorb heat from the device D, thereby effectively cooling the device D.

[0125] As described above, according to this embodiment, the upper sheet 20 includes upper sheet grooves 70 provided on the upper sheet inner surface 20a, which are positioned to overlap the vapor passages 51, 52 in a plan view and extend in a direction intersecting the X direction. This facilitates the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid flow path portion 60. This facilitates the reflux of the working fluids 2a, 2b within the vapor chamber 1. As a result, the heat dissipation efficiency of the vapor chamber 1 can be improved.

[0126] Furthermore, in this embodiment, the cross-sectional area of ​​the upper sheet groove 70 may be smaller than the cross-sectional area of ​​the main liquid flow path groove 61. This allows the capillary action of the upper sheet groove 70 to impart a driving force to the working fluid 2b from the liquid flow path portion 60 toward the upper sheet groove 70, thereby allowing the working fluid 2b in the liquid flow path portion 60 to quickly move through the upper sheet groove 70 to the vapor paths 51 and 52. Therefore, when such an upper sheet groove 70 is disposed in the evaporation region SR, the movement of the working fluid 2b from the liquid flow path portion 60 to the vapor paths 51 and 52 in the evaporation region SR can be effectively promoted. As a result, the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be further promoted.

[0127] Furthermore, in this embodiment, the cross-sectional area of ​​the upper sheet groove 70 may be larger than the cross-sectional area of ​​the main liquid flow path groove 61. This allows the capillary action of the upper sheet groove 70 to apply a driving force to the working fluid 2b from the upper sheet groove 70 toward the liquid flow path section 60, thereby allowing the working fluid 2b in the vapor passages 51, 52 to quickly move through the upper sheet groove 70 to the liquid flow path section 60. Therefore, when such an upper sheet groove 70 is disposed in the condensation region CR, the movement of the working fluid 2b from the vapor passages 51, 52 to the liquid flow path section 60 in the condensation region CR can be effectively promoted. As a result, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be further promoted.

[0128] Furthermore, according to this embodiment, the liquid flow path portion 60 is provided on the wick sheet upper surface 30b. As described above, the upper sheet grooves 70 are provided on the upper sheet inner surface 20a facing the wick sheet upper surface 30b. This allows the working fluid 2b that flows through the upper sheet grooves 70 to move smoothly to the vapor passages 51, 52 or the liquid flow path portion 60. This further promotes the reflux of the working fluids 2a, 2b within the vapor chamber 1.

[0129] In the above-described embodiment, the liquid flow path portion 60 is provided on the upper surface 30b of the wick sheet. However, this is not limiting, and the liquid flow path portion 60 may be provided on the lower surface 30a of the wick sheet, as shown in FIG.

[0130] Even in such a case, the working fluid 2b can flow from the liquid flow path portion 60 along the wall surface 53a of the lower vapor flow path recess 53 and the wall surface 54a of the upper vapor flow path recess 54, into the upper sheet groove 70, and move to the vapor paths 51 and 52. Furthermore, the working fluid 2b can flow from the vapor paths 51 and 52 through the upper sheet groove 70, and move along the wall surface 53a of the lower vapor flow path recess 53 and the wall surface 54a of the upper vapor flow path recess 54, and move to the liquid flow path portion 60. This can promote the reflux of the working fluids 2a and 2b within the vapor chamber 1.

[0131] In the above-described embodiment, as shown in FIG. 13 , the upper sheet groove 70 may be disposed at a position corresponding to the liquid flow path connecting groove 65 located closest to the steam passages 51 and 52 in the liquid flow path section 60. That is, as shown in FIG. 13 , the upper sheet groove 70 may be disposed at the same position in the X direction as the liquid flow path connecting groove 65 located closest to the steam passages 51 and 52 in the liquid flow path section 60, with the first end 71 or the second end 72 facing the liquid flow path connecting groove 65 in the Y direction. Also, as shown in FIG. 13 , the upper sheet groove 70 does not have to be disposed at any position other than the position in the X direction. In this case, by reducing the number of upper sheet grooves 70, it is possible to effectively promote the movement of the working fluid 2b between the steam passages 51 and 52 and the liquid flow path section 60 while suppressing a decrease in the mechanical strength of the upper sheet 20.

[0132] In the above-described embodiment, the planar shape of the upper sheet groove 70 is an elongated rectangular shape (see FIG. 9). However, this is not limited to this. For example, as shown in FIG. 14, the planar shape of the upper sheet groove 70 may be an elongated shape extending in the Y direction with both ends in the Y direction (first end 71 and second end 72) rounded. For example, as shown in FIG. 15, the planar shape of the upper sheet groove 70 may be an elongated oval shape extending in the Y direction. For example, as shown in FIG. 16, the planar shape of the upper sheet groove 70 may be a rosary shape in which multiple circles are connected together, partially overlapping each other in the Y direction. In this way, the planar shape of the upper sheet groove 70 is arbitrary.

[0133] In the above-described embodiment, the cross-sectional shape of the upper sheet groove 70 is described as a semicircular shape (see FIG. 11 ). However, this is not limited thereto. For example, as shown in FIG. 17 , the cross-sectional shape of the upper sheet groove 70 may be triangular. For example, as shown in FIG. 18 , the cross-sectional shape of the upper sheet groove 70 may be rectangular. For example, as shown in FIG. 19 , the cross-sectional shape of the upper sheet groove 70 may be trapezoidal. For example, as shown in FIG. 20 , the cross-sectional shape of the upper sheet groove 70 may be partially circular, the width of which is wider on the inside than the opening. In this way, the cross-sectional shape of the upper sheet groove 70 is arbitrary as long as it has a flow path cross-sectional area smaller than the flow path cross-sectional areas of the steam passages 51 and 52.

[0134] (Second embodiment) Next, a vapor chamber and an electronic device according to a second embodiment of the present disclosure will be described with reference to FIGS.

[0135] 21 and 22, the second embodiment is different in that the first sheet grooves are provided in positions that overlap with the liquid flow path portions in a plan view and that cross the steam path in a direction intersecting the first direction, but other configurations are substantially the same as those of the first embodiment shown in Figures 1 to 20. In Figures 21 and 22, the same parts as those of the first embodiment shown in Figures 1 to 20 are denoted by the same reference numerals and detailed description thereof will be omitted.

[0136] In this embodiment, as shown in Fig. 21, the upper sheet groove 70 is provided in a position that overlaps with the liquid flow path portion 60 in a plan view. That is, the upper sheet groove 70 also overlaps with the land portion 33 in a plan view. As shown in Fig. 21, the upper sheet groove 70 may also overlap with the liquid flow path main groove 61 in a plan view.

[0137] In the present embodiment, the upper sheet groove 70 is provided so as to cross the steam passages 51, 52 in a direction intersecting the X direction. In the example shown in Fig. 21 , the upper sheet groove 70 is provided so as to cross the second steam passage 52 in the Y direction. The first end 71 and the second end 72 of the upper sheet groove 70 are provided at positions overlapping with the land portions 33 in a plan view. More specifically, the first end 71 is provided at a position overlapping with one land portion 33 in a plan view, and the second end 72 is provided at a position overlapping with another land portion 33 adjacent to the one land portion 33 in a plan view.

[0138] As described above, according to this embodiment, the upper sheet groove 70 is provided in a position overlapping the liquid flow path portion 60 in a plan view. This effectively promotes the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid flow path portion 60. Therefore, when such an upper sheet groove 70 is disposed in the evaporation region SR, the movement of the working fluid 2b from the liquid flow path portion 60 to the vapor passages 51, 52 in the evaporation region SR can be effectively promoted. Furthermore, during a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved through the upper sheet groove 70 to the vapor passages 51, 52, effectively promoting the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor passages 51, 52 in the evaporation region SR. Furthermore, when the flow path cross-sectional area of ​​the upper sheet groove 70 is larger than the flow path cross-sectional area of ​​the main liquid flow path groove 61, the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor passages 51, 52 in the evaporation region SR can be even more effectively promoted. As a result, the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be further promoted.

[0139] Furthermore, according to this embodiment, the upper sheet groove 70 is provided so as to cross the vapor passages 51, 52 in a direction intersecting the first direction. This makes it possible, for example, to uniformize the amount of working fluid 2b moving to each liquid flow path portion 60 provided in adjacent lands 33. This makes it possible to prevent a large amount of working fluid 2b from being unevenly distributed in a specific liquid flow path portion 60. As a result, the transport efficiency of the working fluid 2b can be improved, and the reflux of the working fluids 2a, 2b within the vapor chamber 1 can be further promoted.

[0140] In the above-described embodiment, the first end 71 and the second end 72 of the upper seat groove 70 are provided at positions that overlap the land portion 33 in a plan view. However, the present invention is not limited to this, and for example, as shown in Fig. 22, the upper sheet groove 70 may be provided so as to cross the land portion 33 in a direction intersecting the X direction. In the example shown in Fig. 22, the upper sheet groove 70 extends linearly along the Y direction so as to cross the steam passages 51, 52 and the land portion 33 in a plan view.

[0141] Even in this case, the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid flow path 60 can be effectively promoted. Therefore, when such upper sheet grooves 70 are disposed in the evaporation region SR, the movement of the working fluid 2b from the liquid flow path 60 to the vapor passages 51, 52 in the evaporation region SR can be effectively promoted. Furthermore, during a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path 60 can be quickly moved through the upper sheet grooves 70 to the vapor passages 51, 52, effectively promoting the movement of the working vapor 2a from the liquid flow path 60 to the vapor passages 51, 52 in the evaporation region SR. Furthermore, when the cross-sectional area of ​​the upper sheet grooves 70 is larger than the cross-sectional area of ​​the main liquid flow path grooves 61, the movement of the working vapor 2a from the liquid flow path 60 to the vapor passages 51, 52 in the evaporation region SR can be even more effectively promoted. As a result, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be further promoted. Furthermore, the amount of working fluid 2b moving to each liquid flow path section 60 can be made uniform, preventing a large amount of working fluid 2b from being concentrated in a specific liquid flow path section 60. This improves the transport efficiency of the working fluid 2b, and further promotes the reflux of the working fluids 2a, 2b within the vapor chamber 1.

[0142] (Third embodiment) Next, a vapor chamber and an electronic device according to a third embodiment of the present disclosure will be described with reference to FIG.

[0143] The third embodiment shown in Fig. 23 is different mainly in that the first sheet groove includes a first end provided at a position overlapping the steam passage in plan view and a second end provided at a position overlapping the liquid passage portion in plan view, and other configurations are substantially the same as those of the second embodiment shown in Fig. 21 and Fig. 22. Note that in Fig. 23, the same parts as those of the second embodiment shown in Fig. 21 and Fig. 22 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0144] 23 , the upper sheet groove 70 includes a first end 71 provided at a position overlapping the steam passages 51, 52 in a plan view, and a second end 72 provided at a position overlapping the liquid flow path section 60 in a plan view. Here, the first end 71 is defined as the end of both end sections in a direction intersecting the X direction that overlaps with the steam passages 51, 52 in a plan view, and the second end 72 is defined as the end of both end sections in a direction intersecting the X direction that overlaps with the liquid flow path section 60 in a plan view. In the example shown in FIG. 23 , the first end 71 overlaps with the second steam passage 52 in a plan view, and the second end 72 overlaps with the liquid flow path mainstream groove 61 in a plan view.

[0145] 23 , the upper sheet grooves 70 may be provided at positions overlapping the Y-direction positive edge of the land portion 33 in a plan view and at positions overlapping the Y-direction negative edge of the land portion 33 in a plan view. At the positions overlapping the Y-direction positive edge of the land portion 33 in a plan view, the upper sheet grooves 70 may be aligned along the X direction. At the positions overlapping the Y-direction negative edge of the land portion 33 in a plan view, the upper sheet grooves 70 may also be aligned along the X direction.

[0146] As described above, according to this embodiment, the upper sheet groove 70 includes a first end 71 provided at a position overlapping the vapor passages 51 and 52 in a plan view and a second end 72 provided at a position overlapping the liquid flow path portion 60 in a plan view. This effectively promotes the movement of the working fluid 2b between the vapor passages 51 and 52 and the liquid flow path portion 60. Therefore, when such an upper sheet groove 70 is disposed in the evaporation region SR, the movement of the working fluid 2b from the liquid flow path portion 60 to the vapor passages 51 and 52 in the evaporation region SR can be effectively promoted. Furthermore, during a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved through the upper sheet groove 70 to the vapor passages 51 and 52, effectively promoting the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor passages 51 and 52 in the evaporation region SR. Furthermore, when the cross-sectional area of ​​the upper sheet groove 70 is larger than the cross-sectional area of ​​the liquid flow path main groove 61, the movement of the working vapor 2a in the evaporation region SR from the liquid flow path portion 60 to the vapor passages 51 and 52 can be more effectively promoted. As a result, the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be further promoted.

[0147] (Fourth embodiment) Next, a vapor chamber and an electronic device according to a fourth embodiment of the present disclosure will be described with reference to FIG.

[0148] The fourth embodiment shown in Fig. 24 differs mainly in that the first sheet grooves include first sheet grooves provided so as to cross the steam passage in a direction intersecting the first direction, and first sheet grooves including a first end provided at a position overlapping the steam passage in plan view and a second end provided at a position overlapping the liquid flow path portion in plan view, but the other configurations are substantially the same as those of the second embodiment shown in Fig. 21. Note that in Fig. 24, the same parts as those of the second embodiment shown in Fig. 21 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0149] In this embodiment, as shown in FIG. 24 , the multiple upper sheet grooves 70, 70′ include an upper sheet groove 70 arranged to cross the steam passages 51, 52 in a direction intersecting the X direction, and an upper sheet groove 70′ including a first end 71′ arranged at a position overlapping with the steam passages 51, 52 in a plan view and a second end 72′ arranged at a position overlapping with the liquid flow path portion 60 in a plan view.

[0150] 24 , the upper sheet groove 70 is provided so as to cross the second steam passage 52 in the Y direction. A first end 71 and a second end 72 of the upper sheet groove 70 are provided at positions overlapping with the land portions 33 in a plan view. More specifically, the first end 71 is provided at a position overlapping with one land portion 33 in a plan view, and the second end 72 is provided at a position overlapping with another land portion 33 adjacent to the one land portion 33 in a plan view.

[0151] In addition, in the example shown in Figure 24, the first end 71' of the upper sheet groove 70' overlaps with the second steam passage 52 in a planar view, and the second end 72' of the upper sheet groove 70' overlaps with the liquid flow path mainstream groove 61 in a planar view.

[0152] 24, the upper sheet groove 70' may be provided at a position overlapping the edge on the positive side of the Y direction of one land portion 33 (for example, the land portion 33 located in the center in FIG. 24) in a plan view, and at a position overlapping the edge on the negative side of the Y direction of the one land portion 33 in a plan view. The upper sheet grooves 70 and the upper sheet grooves 70' may be arranged alternately in the X direction at positions overlapping the edge on the positive side of the Y direction of the one land portion 33 in a plan view. Furthermore, the upper sheet grooves 70 and the upper sheet grooves 70' may be arranged alternately in the X direction at positions that overlap the edge of the land portion 33 on the negative side in the Y direction in a plan view.

[0153] On the other hand, as shown in Figure 24, the upper sheet grooves 70' do not have to be provided at positions overlapping with the positive edge of the Y direction of another land portion 33 adjacent to the one land portion 33 in plan view (for example, the land portions 33 arranged on the lower and upper sides in Figure 24) and at positions overlapping with the negative edge of the other land portion 33 in plan view. At positions overlapping with the positive edge of the Y direction of the other land portion 33 in plan view, the upper sheet grooves 70 may be aligned along the X direction. Furthermore, at positions overlapping with the negative edge of the Y direction of the other land portion 33 in plan view, the upper sheet grooves 70 may also be aligned alternately in the X direction.

[0154] As described above, according to this embodiment, the multiple upper sheet grooves 70, 70' include an upper sheet groove 70 provided to cross the steam passages 51, 52 in a direction intersecting the X direction, and an upper sheet groove 70' including a first end 71' provided at a position overlapping with the steam passages 51, 52 in a plan view and a second end 72' provided at a position overlapping with the liquid flow path portion 60 in a plan view. This effectively promotes the movement of the working fluid 2b between the steam passages 51, 52 and the liquid flow path portion 60. Therefore, when such an upper sheet groove 70 is disposed in the evaporation region SR, it effectively promotes the movement of the working fluid 2b from the liquid flow path portion 60 to the steam passages 51, 52 in the evaporation region SR. Furthermore, during a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved through the upper sheet groove 70 to the vapor passages 51, 52, effectively facilitating the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor passages 51, 52 in the evaporation region SR. Furthermore, if the flow path cross-sectional area of ​​the upper sheet groove 70 is larger than the flow path cross-sectional area of ​​the main liquid flow path groove 61, the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor passages 51, 52 in the evaporation region SR can be even more effectively promoted. As a result, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be even more effectively promoted.

[0155] In particular, according to this embodiment, it is possible to promote the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid flow path portion 60 provided in one land portion 33. This allows the working fluid 2b to be unevenly distributed among the liquid flow path portions 60. Therefore, for example, it is possible to move more working fluid 2b to a specific liquid flow path portion 60 that has a higher transport capacity for the working fluid 2b than the other liquid flow path portions 60. As a result, it is possible to improve the transport efficiency of the working fluid 2b, and further promote the reflux of the working fluids 2a, 2b within the vapor chamber 1.

[0156] (Fifth embodiment) Next, a vapor chamber and an electronic device according to a fifth embodiment of the present disclosure will be described with reference to FIG.

[0157] The fifth embodiment shown in Fig. 25 is different from the third embodiment shown in Fig. 23 in that the first seat groove is formed so that the flow path cross-sectional area becomes smaller from the second end to the first end, and other configurations are substantially the same as those of the third embodiment shown in Fig. 23. In Fig. 25, the same parts as those of the third embodiment shown in Fig. 23 are denoted by the same reference numerals and detailed description thereof will be omitted.

[0158] In this embodiment, as shown in Fig. 25, the upper sheet groove 70 is formed so that the flow path cross-sectional area decreases from the second end 72 to the first end 71. That is, the upper sheet groove 70 is formed so that it tapers from the second end 72 to the first end 71. For example, the upper sheet groove 70 may be formed so that the width w6 of the upper sheet groove 70 decreases from the second end 72 to the first end 71. Furthermore, the upper sheet groove 70 may be formed so that the depth h2 of the upper sheet groove 70 decreases from the second end 72 to the first end 71.

[0159] As described above, according to this embodiment, the upper sheet groove 70 is formed so that the flow path cross-sectional area decreases from the second end 72 to the first end 71. As a result, the capillary action of the upper sheet groove 70 applies a driving force to the working fluid 2b from the liquid flow path portion 60 toward the upper sheet groove 70, allowing the working fluid 2b in the liquid flow path portion 60 to quickly move through the upper sheet groove 70 to the vapor paths 51 and 52. Therefore, when such an upper sheet groove 70 is disposed in the evaporation region SR, the movement of the working fluid 2b from the liquid flow path portion 60 to the vapor paths 51 and 52 in the evaporation region SR can be effectively promoted. Furthermore, during a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved through the upper sheet groove 70 to the vapor paths 51 and 52, effectively promoting the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor paths 51 and 52 in the evaporation region SR. Furthermore, when the cross-sectional area of ​​the upper sheet groove 70 is larger than the cross-sectional area of ​​the liquid flow path main groove 61, the movement of the working vapor 2a in the evaporation region SR from the liquid flow path portion 60 to the vapor passages 51 and 52 can be more effectively promoted. As a result, the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be further promoted.

[0160] (Sixth embodiment) Next, a vapor chamber and an electronic device according to a sixth embodiment of the present disclosure will be described with reference to FIG.

[0161] The sixth embodiment shown in Fig. 26 is different from the third embodiment shown in Fig. 23 in that the first seat groove is formed so that the flow path cross-sectional area becomes smaller from the first end to the second end, and other configurations are substantially the same as those of the third embodiment shown in Fig. 23. In Fig. 26, the same parts as those of the third embodiment shown in Fig. 23 are denoted by the same reference numerals and detailed description thereof will be omitted.

[0162] In this embodiment, as shown in Fig. 26, the upper sheet groove 70 is formed so that the flow path cross-sectional area decreases from the first end 71 to the second end 72. That is, the upper sheet groove 70 is formed so that it tapers from the first end 71 to the second end 72. For example, the upper sheet groove 70 may be formed so that the width w6 of the upper sheet groove 70 decreases from the first end 71 to the second end 72. Furthermore, the upper sheet groove 70 may be formed so that the depth h2 of the upper sheet groove 70 decreases from the first end 71 to the second end 72.

[0163] As described above, according to this embodiment, the upper sheet groove 70 is formed so that the flow path cross-sectional area decreases from the first end 71 to the second end 72. As a result, the capillary action of the upper sheet groove 70 applies a driving force to the working fluid 2b from the upper sheet groove 70 toward the liquid flow path portion 60, allowing the working fluid 2b in the vapor flow paths 51 and 52 to quickly move through the upper sheet groove 70 to the liquid flow path portion 60. Therefore, when such an upper sheet groove 70 is disposed in the condensation region CR, the movement of the working fluid 2b from the vapor flow paths 51 and 52 to the liquid flow path portion 60 in the condensation region CR can be effectively promoted. Furthermore, when such an upper sheet groove 70 is disposed in the evaporation region SR, in the event of a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved through the upper sheet groove 70 to the vapor flow paths 51 and 52, effectively promoting the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor flow paths 51 and 52 in the evaporation region SR. Furthermore, when the cross-sectional area of ​​the upper sheet groove 70 is larger than the cross-sectional area of ​​the liquid flow path main groove 61, the movement of the working vapor 2a in the evaporation region SR from the liquid flow path portion 60 to the vapor passages 51 and 52 can be more effectively promoted. As a result, the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be further promoted.

[0164] (Seventh embodiment) Next, a vapor chamber and an electronic device according to a seventh embodiment of the present disclosure will be described with reference to FIGS.

[0165] The seventh embodiment shown in Figures 27 to 29 is different mainly in that the first seat groove is arranged so as to be inclined with respect to the first direction in plan view, and other configurations are substantially the same as those of the third embodiment shown in Figure 23. In Figures 27 to 29, the same parts as those of the third embodiment shown in Figure 23 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0166] In this embodiment, as shown in Figure 27, the upper sheet groove 70 is disposed so as to be inclined with respect to the X direction in a plan view. The inclination angle of the upper sheet groove 70 can be any angle greater than 0 degrees and less than 90 degrees. It can also be said that the upper sheet groove 70 is inclined with respect to the Y direction in a plan view.

[0167] 27, at a position overlapping the edge of the land portion 33 on the positive side in the Y direction in plan view, each upper sheet groove 70 is inclined so that the first end 71 is located further to the positive side in the X direction and the positive side in the Y direction than the second end 72. Furthermore, at a position overlapping the edge of the land portion 33 on the positive side in the Y direction in plan view, each upper sheet groove 70 is aligned parallel to one another in the X direction. In the example shown in FIG. 27, four upper sheet grooves 70 are aligned.

[0168] On the other hand, at a position overlapping the edge of the land portion 33 on the negative side in the Y direction in plan view, each upper sheet groove 70 is inclined so that the first end 71 is located further to the positive side in the X direction and the negative side in the Y direction than the second end 72. Furthermore, at a position overlapping the edge of the land portion 33 on the negative side in the Y direction in plan view, each upper sheet groove 70 is aligned parallel to one another in the X direction. In the example shown in FIG. 27 , four upper sheet grooves 70 are aligned.

[0169] Each upper seat groove 70 may be disposed near an end of the vapor chamber 1 (for example, an end on the negative side in the X direction of the vapor chamber 1). However, this is not limited thereto, and each upper seat groove 70 may be disposed at any position of the vapor chamber 1.

[0170] As described above, according to this embodiment, the upper sheet groove 70 is arranged to be inclined with respect to the X direction in a plan view. This allows, for example, the working fluid 2b in the vapor passages 51 and 52 to move so as to concentrate toward the liquid flow path section 60 in the condensation region CR. In particular, even when the liquid flow path section 60 is located near the end of the vapor chamber 1, a sufficient amount of working fluid 2b can be moved to the liquid flow path section 60. Furthermore, when such an upper sheet groove 70 is arranged in the evaporation region SR, in the event of a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path section 60 can be quickly moved through the upper sheet groove 70 to the vapor passages 51 and 52. This effectively promotes the movement of the working vapor 2a from the liquid flow path section 60 to the vapor passages 51 and 52 in the evaporation region SR. In particular, when the upper sheet groove 70 is inclined so that the first end 71 faces the condensation region CR, the flow of the working vapor 2a can be directed toward the condensation region CR, allowing the working vapor 2a to be quickly transported to the condensation region CR. Therefore, the transport efficiency of the working fluid 2b can be improved, and the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be promoted.

[0171] In the above-described embodiment, the upper sheet grooves 70 are aligned parallel to each other in the X direction at positions that overlap the edges of the lands 33 in a plan view. However, this is not limiting, and the upper sheet grooves 70 do not have to be parallel to each other, as shown in Figures 28 and 29.

[0172] 28 , six upper sheet grooves 70 are aligned along the X direction at positions that overlap the edges of the land portions 33 on the positive side in the Y direction in a plan view. Of these upper sheet grooves 70, three upper sheet grooves 70 located on the negative side in the X direction are inclined so that their first ends 71 ​​are located further on the negative side in the X direction and on the positive side in the Y direction than their second ends 72. Similarly, three upper sheet grooves 70 located on the positive side in the X direction are inclined so that their first ends 71 ​​are located further on the positive side in the X direction and on the positive side in the Y direction than their second ends 72.

[0173] Meanwhile, six upper seat grooves 70 are also aligned along the X direction at positions that overlap with the edge of the land portion 33 on the negative side in the Y direction in a plan view. Of these upper seat grooves 70, three upper seat grooves 70 located on the negative side in the X direction are inclined so that their first ends 71 ​​are located further to the negative side in the X direction and the negative side in the Y direction than their second ends 72. Similarly, three upper seat grooves 70 located on the positive side in the X direction are inclined so that their first ends 71 ​​are located further to the positive side in the X direction and the negative side in the Y direction than their second ends 72.

[0174] In this case, for example, the working fluid 2b in the vapor passages 51 and 52 can be moved so as to concentrate in the liquid flow path section 60 in the condensation region CR. This allows a sufficient amount of working fluid 2b to be moved to the liquid flow path section 60. Furthermore, if such upper sheet grooves 70 are provided in the evaporation region SR, during a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path section 60 can be quickly moved through the upper sheet grooves 70 to the vapor passages 51 and 52. This effectively promotes the movement of the working vapor 2a from the liquid flow path section 60 to the vapor passages 51 and 52 in the evaporation region SR. In particular, when multiple condensation regions CR are provided, the flow of the working vapor 2a can be directed toward each condensation region CR, allowing the working vapor 2a to be quickly transported to each condensation region CR. This improves the transport efficiency of the working fluid 2b and promotes the reflux of the working fluids 2a and 2b in the vapor chamber 1.

[0175] 29, six upper sheet grooves 70 are aligned along the X direction at positions that overlap the edges of the land portions 33 on the positive side in the Y direction in a plan view. Of these upper sheet grooves 70, three upper sheet grooves 70 located on the negative side in the X direction are inclined so that their first ends 71 ​​are located further to the positive side in the X direction and the positive side in the Y direction than their second ends 72. Similarly, three upper sheet grooves 70 located on the positive side in the X direction are inclined so that their first ends 71 ​​are located further to the negative side in the X direction and the positive side in the Y direction than their second ends 72.

[0176] Meanwhile, six upper seat grooves 70 are also aligned along the X direction at positions that overlap with the edge of the land portion 33 on the negative side in the Y direction in a plan view. Of these upper seat grooves 70, three upper seat grooves 70 located on the negative side in the X direction are inclined so that their first ends 71 ​​are located further to the positive side in the X direction and the negative side in the Y direction than their second ends 72. Similarly, three upper seat grooves 70 located on the positive side in the X direction are inclined so that their first ends 71 ​​are located further to the negative side in the X direction and the negative side in the Y direction than their second ends 72.

[0177] In this case, for example, the working fluid 2b in the liquid flow path portion 60 can be moved so as to concentrate in the vapor passages 51 and 52 in the evaporation region SR. This allows the working fluid 2b to be efficiently evaporated in the evaporation region SR. This promotes the reflux of the working fluids 2a and 2b in the vapor chamber 1.

[0178] (Eighth embodiment) Next, a vapor chamber and an electronic device according to an eighth embodiment of the present disclosure will be described with reference to FIGS.

[0179] The eighth embodiment shown in Figures 30 and 31 differs mainly in that the first seat grooves are arranged radially in plan view, and other configurations are substantially the same as those of the third embodiment shown in Figure 23. In Figures 30 and 31, the same parts as those of the third embodiment shown in Figure 23 are designated by the same reference numerals and detailed description thereof will be omitted.

[0180] In this embodiment, as shown in Fig. 30, the multiple upper sheet grooves 70 are arranged radially in a plan view. In the example shown in Fig. 30, each upper sheet groove 70 is arranged so as to be inclined with respect to the X direction. Furthermore, each upper sheet groove 70 is arranged so that its second end 72 faces a specific position of the liquid flow path section 60. The upper sheet grooves 70 are arranged radially so that a gap w7 (see Fig. 11) between adjacent upper sheet grooves 70 in the X direction becomes smaller going from the steam passages 51, 52 side to the liquid flow path section 60 side.

[0181] As described above, according to this embodiment, the upper sheet grooves 70 are arranged radially in a plan view. This allows, for example, the working fluid 2b in the vapor passages 51 and 52 to move so as to concentrate toward the liquid flow path section 60 in the condensation region CR. This allows a sufficient amount of working fluid 2b to move to the liquid flow path section 60. Furthermore, when such upper sheet grooves 70 are arranged in the evaporation region SR, in the event of a sudden temperature rise, the working vapor 2a evaporated from the working fluid 2b in the liquid flow path section 60 can be quickly moved through the upper sheet grooves 70 to the vapor passages 51 and 52. This effectively promotes the movement of the working vapor 2a from the liquid flow path section 60 to the vapor passages 51 and 52 in the evaporation region SR. In particular, when multiple condensation regions CR are arranged, the flow of the working vapor 2a can be directed toward each condensation region CR, allowing the working vapor 2a to be quickly transported to each condensation region CR. As a result, the transport efficiency of the working fluid 2b can be improved, and the reflux of the working fluids 2a and 2b within the vapor chamber 1 can be promoted.

[0182] In the above-described embodiment, the upper sheet grooves 70 are radially arranged such that the gap w7 between adjacent upper sheet grooves 70 in the X direction decreases from the steam passages 51, 52 toward the liquid flow path 60. However, this is not limiting, and for example, as shown in FIG. 31 , the upper sheet grooves 70 may be radially arranged such that the gap w7 between adjacent upper sheet grooves 70 in the X direction decreases from the liquid flow path 60 toward the steam passages 51, 52. Each upper sheet groove 70 may be arranged such that its first end 71 faces a specific position on the steam passages 51, 52.

[0183] In this case, for example, the working fluid 2b in the liquid flow path portion 60 can be moved so as to concentrate in the vapor passages 51 and 52 in the evaporation region SR. This allows the working fluid 2b to be efficiently evaporated in the evaporation region SR. This promotes the reflux of the working fluids 2a and 2b in the vapor chamber 1.

[0184] (Ninth embodiment) Next, a vapor chamber and an electronic device according to a ninth embodiment of the present disclosure will be described with reference to FIGS.

[0185] The ninth embodiment shown in Figures 32 to 34 is different mainly in that the first sheet includes a communication groove that connects adjacent first sheet grooves, and other configurations are substantially the same as those of the second embodiment shown in Figures 21 and 22. In Figures 32 to 34, the same parts as those of the second embodiment shown in Figures 21 and 22 are designated by the same reference numerals and detailed description thereof will be omitted.

[0186] In this embodiment, as shown in FIG. 32 , the upper sheet 20 includes an upper sheet communication groove 75 (communication groove) that communicates adjacent upper sheet grooves 70. The upper sheet 20 may include multiple upper sheet communication grooves 75. In the example shown in FIG. 32 , each upper sheet groove 70 extends along the Y direction. Each upper sheet groove 70 is provided so as to cross the second steam passage 52 in the Y direction. Each upper sheet communication groove 75 is arranged at a position overlapping with the second steam passage 52 in a plan view. Each upper sheet communication groove 75 extends along the X direction. Each upper sheet communication groove 75 is connected to adjacent upper sheet grooves 70.

[0187] The upper seat communication groove 75 has a small flow path cross-sectional area so that the working fluid 2b flows mainly by capillary action. The flow path cross-sectional area of ​​the upper seat communication groove 75 is smaller than the flow path cross-sectional area of ​​the steam passages 51, 52. The flow path cross-sectional area of ​​the upper seat communication groove 75 may be equal to the flow path cross-sectional area of ​​the upper seat groove 70. However, this is not limited thereto, and the flow path cross-sectional area of ​​the upper seat communication groove 75 may be smaller or larger than the flow path cross-sectional area of ​​the upper seat groove 70.

[0188] The upper sheet communicating groove 75 may be formed by etching the upper sheet 20 from the upper sheet inner surface 20a, similar to the upper sheet groove 70. As a result, the upper sheet communicating groove 75 may have a wall surface (not shown) formed in a curved shape similar to the upper sheet groove 70. Furthermore, the upper sheet communicating groove 75 may be formed integrally and continuously with the upper sheet groove 70.

[0189] The upper sheet communication grooves 75 may be aligned in the X and Y directions. Alternatively, as shown in Fig. 32, the upper sheet communication grooves 75 may be arranged in a staggered pattern. That is, the upper sheet communication grooves 75 adjacent to each other in the X direction may be shifted from each other in the Y direction. The amount of this shift may be half the arrangement pitch of the upper sheet communication grooves 75 in the X direction.

[0190] As described above, according to this embodiment, the upper sheet 20 includes upper sheet communication grooves 75 that communicate with adjacent upper sheet grooves 70. This allows the hydraulic fluid 2b to move between the upper sheet grooves 70 by the capillary action of the upper sheet communication grooves 75. This prevents uneven distribution of the working fluid 2b between the upper sheet grooves 70. As a result, the transport efficiency of the working fluid 2b can be improved, and the reflux of the working fluids 2a and 2b within the vapor chamber 1 can be further promoted.

[0191] In the above-described embodiment, an example has been described in which the upper sheet grooves 70 are provided so as to cross the second steam passage 52 in the Y direction, and the upper sheet communication grooves 75 are arranged in a staggered pattern. However, this is not limiting, and the upper sheet grooves 70 and the upper sheet communication grooves 75 may be arranged in any desired manner.

[0192] 33, the upper sheet grooves 70 are arranged in a staggered pattern. That is, the upper sheet grooves 70 adjacent to each other in the X direction are shifted relative to each other in the Y direction. This shift may be half the arrangement pitch of the upper sheet grooves 70 in the X direction.

[0193] In the example shown in FIG. 33, each upper sheet communication groove 75 extends linearly along the X direction. Each upper sheet communication groove 75 is connected to an end (first end 71 or second end 72) of each upper sheet groove 70, thereby communicating the upper sheet grooves 70, 70′. Each upper sheet communication groove 75 is disposed at a position overlapping with the second steam passage 52 in a plan view. Each upper sheet communication groove 75 is aligned along the Y direction. In the example shown in FIG. 33, three upper sheet communication grooves 75 are aligned parallel to each other.

[0194] Even in such a case, the capillary action of the upper sheet communication grooves 75 allows the working fluid 2b to move between the upper sheet grooves 70. This prevents the working fluid 2b from being unevenly distributed between the upper sheet grooves 70. As a result, the transport efficiency of the working fluid 2b can be improved, and the reflux of the working fluids 2a, 2b within the vapor chamber 1 can be further promoted.

[0195] In the above-described embodiment, the upper sheet communication grooves 75 are arranged in a staggered pattern. However, this is not limiting, and the upper sheet communication grooves 75 may be arranged in a grid pattern as shown in Fig. 34. That is, the upper sheet communication grooves 75 may be aligned in the X and Y directions.

[0196] Even in such a case, the capillary action of the upper sheet communication grooves 75 allows the working fluid 2b to move between the upper sheet grooves 70. This prevents the working fluid 2b from being unevenly distributed between the upper sheet grooves 70. As a result, the transport efficiency of the working fluid 2b can be improved, and the reflux of the working fluids 2a, 2b within the vapor chamber 1 can be further promoted.

[0197] (Tenth embodiment) Next, a vapor chamber and an electronic device according to a tenth embodiment of the present disclosure will be described with reference to FIG.

[0198] The tenth embodiment shown in Figure 35 differs mainly in that a liquid flow path portion is also provided on the second main body surface, and the second sheet includes a second sheet groove provided on the inner surface of the second sheet, the second sheet groove being provided at a position overlapping the steam path in a plan view and extending along a direction intersecting the first direction, but the other configurations are substantially the same as those of the first embodiment shown in Figures 1 to 20. Note that in Figure 35, the same parts as those of the first embodiment shown in Figures 1 to 20 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0199] In this embodiment, as shown in Figure 35, the liquid flow path section 60 is also provided on the lower surface 30a of the wick sheet. That is, the liquid flow path section 60 is provided on the upper surface 30b of the wick sheet, and also on the lower surface 30a of the wick sheet.

[0200] In this embodiment, as shown in FIG. 35 , the lower sheet 10 includes a lower sheet groove 80 (second sheet groove) provided in the lower sheet inner surface 10b. The lower sheet 10 may include multiple lower sheet grooves 80. Like the upper sheet groove 70, the lower sheet groove 80 is provided at a position overlapping with the steam passages 51 and 52 in a plan view. The lower sheet groove 80 may be provided at a position facing the upper sheet groove 70. Like the upper sheet groove 70, the lower sheet groove 80 extends along a direction intersecting the X direction. Like the upper sheet groove 70, the lower sheet groove 80 may extend along the Y direction perpendicular to the X direction. Other configurations of the lower sheet groove 80 are similar to those of the upper sheet groove 70 described above.

[0201] As described above, according to this embodiment, the liquid flow path portion 60 is also provided on the lower surface 30a of the wick sheet, which makes it possible to effectively utilize the space within the vapor chamber 1 and further promote the circulation of the working fluids 2a and 2b within the vapor chamber 1.

[0202] Furthermore, according to this embodiment, the lower sheet 10 includes lower sheet grooves 80 provided on the lower sheet inner surface 10b, which are positioned to overlap the vapor passages 51, 52 in a plan view and extend in a direction intersecting the X direction. This further promotes the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid passage portion 60 when the liquid passage portion 60 is also provided on the wick sheet lower surface 30a. This further promotes the reflux of the working fluids 2a, 2b within the vapor chamber 1.

[0203] (Eleventh embodiment) Next, a vapor chamber and an electronic device according to an eleventh embodiment of the present disclosure will be described with reference to FIG.

[0204] The eleventh embodiment shown in Fig. 36 is different mainly in that the first sheet has a recessed region recessed toward the steam passage, and the first sheet groove is disposed in the recessed region, but other configurations are substantially the same as those of the first embodiment shown in Fig. 1 to Fig. 20. In Fig. 36, the same parts as those of the first embodiment shown in Fig. 1 to Fig. 20 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0205] In this embodiment, as shown in Fig. 36, the vapor chamber 1 includes a flat region FR in which the upper sheet 20 is formed flat, and a recessed region DR in which the upper sheet 20 is recessed toward the vapor passages 51 and 52 of the vapor flow path section 50. In the flat region FR, the lower sheet 10 may also be formed flat. In the recessed region DR, the lower sheet 10 may also be recessed toward the vapor passages 51 and 52 of the vapor flow path section 50. The recessed region DR can be formed by partially pressing the flat vapor chamber 1 from the outside or by bending the flat vapor chamber 1.

[0206] In this embodiment, the upper sheet groove 70 is disposed in the recessed region DR as shown in Fig. 36. That is, the upper sheet groove 70 is provided in a portion of the upper sheet inner surface 20a that is located in the recessed region DR. On the other hand, the upper sheet groove 70 does not necessarily have to be provided in a region other than the recessed region DR, i.e., in the flat region FR.

[0207] As described above, according to this embodiment, the upper sheet groove 70 is disposed in the recessed region DR. In the recessed region DR, the flow path cross-sectional area of ​​the vapor passages 51, 52 is smaller than the flow path cross-sectional area of ​​the vapor passages 51, 52 in other regions. As a result, the working vapor 2a is likely to condense and the working fluid 2b is likely to be generated in the recessed region DR. This may result in the working fluid 2b accumulating in the recessed region DR. In contrast, by disposing the upper sheet groove 70 in the recessed region DR, the flow of the working fluid 2b between the vapor passages 51, 52 and the liquid flow path portion 60 in the recessed region DR can be promoted. This prevents the working fluid 2b from accumulating in the recessed region DR. As a result, the reflux of the working fluids 2a, 2b within the vapor chamber 1 can be effectively promoted.

[0208] (Twelfth embodiment) Next, a vapor chamber and an electronic device according to a twelfth embodiment of the present disclosure will be described with reference to FIG.

[0209] The twelfth embodiment shown in Fig. 37 differs mainly in that the first seat groove is provided at a position that overlaps the connecting portion in a plan view, and other configurations are substantially the same as those of the first embodiment shown in Figs. 1 to 20. In Fig. 37, the same parts as those of the first embodiment shown in Figs. 1 to 20 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0210] In this embodiment, as shown in Figure 37, the upper seat groove 70 is provided at a position overlapping the connecting portion 38 in a plan view. It can also be said that the upper seat groove 70 is provided at a position facing the connecting portion 38. Here, as described above, the connecting portion 38 is a member that connects adjacent lands 33.

[0211] 37, the connecting portions 38 are disposed in a position close to the wick sheet lower surface 30a of the wick sheet 30. More specifically, the connecting portions 38 are disposed in the space forming the lower steam flow path recesses 53 of the steam passages 51, 52. The upper steam flow path recesses 54 of the steam passages 51, 52 are secured in a position close to the wick sheet upper surface 30b of the wick sheet 30. The upper sheet grooves 70 do not have to be provided in any position other than the position facing the connecting portions 38.

[0212] According to this embodiment, the upper sheet groove 70 is located at a position overlapping the connecting portion 38 in a plan view. At the position where the connecting portion 38 is located, the flow path cross-sectional area of ​​the vapor passages 51, 52 is smaller than the flow path cross-sectional area of ​​the vapor passages 51, 52 at other positions. As a result, the working steam 2a is likely to condense and produce working fluid 2b at the position where the connecting portion 38 is located. This could result in the working fluid 2b accumulating at this position. In contrast, by arranging the upper sheet groove 70 at a position overlapping the connecting portion 38 in a plan view, the flow of working fluid 2b between the vapor passages 51, 52 and the liquid flow path portion 60 at this position is promoted, thereby preventing the working fluid 2b from accumulating. This effectively promotes the reflux of the working fluids 2a, 2b within the vapor chamber 1.

[0213] (Thirteenth embodiment) Next, a vapor chamber and an electronic device according to a thirteenth embodiment of the present disclosure will be described with reference to FIG.

[0214] The thirteenth embodiment shown in Fig. 38 is different mainly in that the first seat groove is provided in an area adjacent to the connecting portion along the first direction in plan view, and other configurations are substantially the same as those of the first embodiment shown in Figs. 1 to 20. In Fig. 38, the same parts as those of the first embodiment shown in Figs. 1 to 20 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0215] 38, in this embodiment, the upper sheet groove 70 is provided in a region adjacent to the connecting portion 38 along the X direction in a plan view. Here, the connecting portion 38 is a member that connects the adjacent lands 33, as described above.

[0216] The connecting portion 38 may be located near the wick sheet lower surface 30a of the wick sheet 30. The connecting portion 38 may be located in the space forming the lower steam flow path recess 53 of the steam passages 51, 52, and the upper steam flow path recess 54 of the steam passages 51, 52 may be provided near the wick sheet upper surface 30b of the wick sheet 30. The upper sheet groove 70 does not have to be provided in a position other than the region adjacent to the connecting portion 38 along the X direction in plan view, i.e., not in a position distant from the connecting portion 38 in plan view. Here, the region adjacent to the connecting portion 38 along the X direction in plan view may be, for example, a region within 300 μm, 150 μm, or 50 μm from the connecting portion 38 in the X direction in plan view.

[0217] In the example shown in FIG. 38, the upper sheet grooves 70 are provided in the regions adjacent to the connecting portion 38 along the X direction in a plan view, on both sides in the X direction, but this is not limited thereto, and the upper sheet grooves 70 may be provided in the regions on either side in the X direction.

[0218] Also, in the example shown in Figure 38, the upper sheet groove 70 is not provided at a position that overlaps with the connecting portion 38 in a planar view, but this is not limited to this, and the upper sheet groove 70 may also be provided at a position that overlaps with the connecting portion 38 in a planar view.

[0219] According to this embodiment, the upper sheet groove 70 is provided in a region adjacent to the connecting portion 38 along the X direction in a plan view. The cross-sectional areas of the vapor passages 51, 52 at the location where the connecting portion 38 is provided are smaller than the cross-sectional areas of the vapor passages 51, 52 at other locations. This facilitates condensation of the working vapor 2a and generation of the working fluid 2b in the region adjacent to the connecting portion 38 along the X direction. This may result in accumulation of the working fluid 2b in this region. In contrast, by providing the upper sheet groove 70 in a region adjacent to the connecting portion 38 along the X direction in a plan view, the flow of the working fluid 2b between the vapor passages 51, 52 and the liquid passage portion 60 in this region is facilitated, thereby preventing accumulation of the working fluid 2b. This effectively facilitates reflux of the working fluids 2a, 2b within the vapor chamber 1.

[0220] (Fourteenth embodiment) Next, a vapor chamber and an electronic device according to a fourteenth embodiment of the present disclosure will be described with reference to FIGS.

[0221] The fourteenth embodiment shown in Figures 39 and 40 differs mainly in that the vapor chamber has a bent region bent along a bend line, and the first seat groove is disposed in the bent region, but other configurations are substantially the same as those of the first embodiment shown in Figures 1 to 20. In Figures 39 and 40, the same parts as those of the first embodiment shown in Figures 1 to 20 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0222] In this embodiment, the vapor chamber 1 is bent along a bending line BL shown in FIG. 39. FIG. 39 shows a flat vapor chamber 1 before bending. In the example shown in FIG. 39, the bending line BL is provided in the center of the vapor chamber 1 in the X direction and extends along the Y direction. By bending the vapor chamber 1 along the bending line BL, a curved vapor chamber 1 can be obtained, as shown in FIG. 40, in which the vapor chamber 1 is bent along the bending line BL to form a bending region BR, and the vapor chamber 1 includes a first region RR1 and a second region RR2 separated by the bending region BR. As shown in FIG. 40, a device D may be attached to the first region RR1, and a housing member Ha may be attached to the second region RR2.

[0223] The vapor chamber 1 may be bent so that the lower sheet 10 is positioned inside and the upper sheet 20 is positioned outside. The bending angle may be any angle. In the example shown in FIG. 40, the bending angle is 90 degrees (a right angle). Therefore, the cross-sectional shape of the vapor chamber 1 is approximately L-shaped. However, this is not limited to this. For example, the vapor chamber 1 may be bent so that the cross-sectional shape of the vapor chamber 1 is U-shaped. For example, the vapor chamber 1 may be bent multiple times so that the cross-sectional shape of the vapor chamber 1 is U-shaped. Bending the vapor chamber 1 in this manner improves the degree of freedom in the placement of the vapor chamber 1 within the housing H. Here, the bending angle refers to the angle formed between the lower sheet outer surface 10a or the upper sheet outer surface 20b in the first region RR1 of the vapor chamber 1 and the lower sheet outer surface 10a or the upper sheet outer surface 20b in the second region RR2 of the vapor chamber 1.

[0224] Such a curved vapor chamber 1 can be produced by bending the flat vapor chamber 1 along the bending line BL in a bending step after the sealing step in the manufacturing process of the vapor chamber 1.

[0225] In this embodiment, the upper sheet groove 70 is arranged in the bending region BR. That is, the upper sheet groove 70 is provided on the upper sheet inner surface 20a of the upper sheet 20 in the bending region BR. The upper sheet groove 70 does not have to be arranged in regions other than the bending region BR, that is, in the first region RR1 and the second region RR2.

[0226] As described above, according to this embodiment, the upper sheet groove 70 is disposed in the bending region BR. When the vapor chamber 1 is bent, the lower sheet 10 located on the inside may receive compressive stress in the bending region BR and deform so as to be recessed toward the lower vapor flow path recess 53. Furthermore, the upper sheet 20 located on the outside may receive tensile stress in the bending region BR and deform so as to be recessed toward the upper vapor flow path recess 54. As a result, a recessed region DR may be formed in the bending region BR of the bent vapor chamber 1, as described in the eleventh embodiment using FIG. 36 . Therefore, the flow path cross-sectional area of ​​the vapor passages 51, 52 may be reduced in the bending region BR. This may facilitate condensation of the working vapor 2a and generation of the working fluid 2b in the bending region BR. Therefore, there is a risk of the working fluid 2b accumulating in the bending region BR. In contrast, by disposing the upper sheet groove 70 in the bending region BR, the flow path of the working fluid 2b between the steam passages 51, 52 and the liquid flow path portion 60 can be facilitated in the bending region BR. Therefore, it is possible to prevent the working fluid 2b from accumulating in the curved region BR, and as a result, it is possible to effectively promote the reflux of the working fluids 2a and 2b in the vapor chamber 1.

[0227] In particular, in a curved vapor chamber 1, the working vapor 2a is likely to condense and produce working fluid 2b on the upper sheet inner surface 20a of the upper sheet 20 located on the outer side. As described above, the upper sheet grooves 70 are provided on the upper sheet inner surface 20a. This allows, for example, the working fluid 2b condensed on the upper sheet inner surface 20a to quickly move to the liquid flow path portion 60 by capillary action of the upper sheet grooves 70. Therefore, when the vapor chamber 1 is curved so that the lower sheet 10 is located on the inner side and the upper sheet 20 is located on the outer side, the movement of the working fluid 2b from the vapor passages 51 and 52 to the liquid flow path portion 60 in the condensation region CR can be effectively promoted. As a result, the reflux of the working fluids 2a and 2b within the vapor chamber 1 can be further promoted.

[0228] In the above-described embodiments, an example has been described in which the vapor chamber 1 is composed of a lower sheet 10, an upper sheet 20, and a wick sheet 30. However, this is not limited to this, and the vapor chamber 1 may be composed of an upper sheet 20 and a wick sheet 30, as shown in FIG.

[0229] 41, the vapor chamber 1 includes an upper sheet 20 and a wick sheet 30, but does not include a lower sheet 10. In this case, the housing member Ha may be attached to the wick sheet lower surface 30a of the wick sheet 30. Heat of the working vapor 2a is transferred from the wick sheet 30 to the housing member Ha.

[0230] 41, the vapor flow path section 50 is provided on the upper surface 30b of the wick sheet, but does not extend to the lower surface 30a of the wick sheet, and does not penetrate the wick sheet 30. In other words, the first vapor passage 51 and the second vapor passage 52 of the vapor flow path section 50 are formed by an upper vapor flow path recess 54, and the wick sheet 30 is not provided with a lower vapor flow path recess 53.

[0231] 41, an upper sheet groove 70 is provided in a position facing the steam flow path portion 50 of the upper sheet 20. That is, the upper sheet 20 includes the upper sheet groove 70 provided in the upper sheet inner surface 20a, at a position overlapping with the steam passages 51, 52 in a plan view.

[0232] The thickness t5 of the vapor chamber 1 shown in Fig. 41 may be, for example, 100 µm to 1000 µm. The thickness t6 of the upper sheet 20 shown in Fig. 41 may be, for example, 6 µm to 200 µm. The thickness t7 of the wick sheet 30 shown in Fig. 41 may be, for example, 50 µm to 800 µm.

[0233] 41, the liquid flow path section 60 is not provided on the upper sheet inner surface 20a of the upper sheet 20, but this is not limited thereto, and the liquid flow path section 60 may be provided on the upper sheet inner surface 20a of the upper sheet 20. In this case, the liquid flow path section 60 of the upper sheet 20 may be provided in a position facing the liquid flow path section 60 of the wick sheet 30.

[0234] In this way, the vapor chamber 1 may be composed of the upper sheet 20 and the wick sheet 30. Even in this case, the upper sheet 20 includes the upper sheet grooves 70, which can promote the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid passage portion 60. This can promote the reflux of the working fluids 2a, 2b within the vapor chamber 1. In this case, the vapor chamber 1 can be made even thinner.

[0235] (Fifteenth embodiment) Next, a vapor chamber and an electronic device according to a fifteenth embodiment of the present disclosure will be described with reference to FIGS.

[0236] The vapor chamber may be bent depending on the internal structure of the electronic device in which it is installed. In this case, the vapor flow path is bent and tends to collapse. This increases the flow resistance, which can hinder the flow of working vapor within the vapor flow path.

[0237] The present embodiment aims to provide a vapor chamber and an electronic device that can improve heat dissipation efficiency even when bent.

[0238] Vapor chamber 101 according to this embodiment is bent as shown in Figures 42 and 43. Vapor chamber 101 is bent in accordance with the internal structure of electronic device E. The vapor chamber 101 may be bent depending on the positional relationship between the electronic device E that generates heat and the housing member Ha that dissipates the heat. The housing member Ha is a member that constitutes the housing H.

[0239] As an example, an electronic device D and a housing member Ha are arranged as shown in FIG. 42. In this case, the vapor chamber 101 is bent at a right angle so as to contact the electronic device D and the housing member Ha. The electronic device D is mounted on a substrate S. The vapor chamber 101 may be bonded to the substrate S using an adhesive AD. The adhesive AD may be bonded to a bending region 107, which will be described later, or to a first region 105 or a second region 106, which will be described later. As another example, an electronic device D and a housing member Ha are arranged as shown in FIG. 43. In this case, the vapor chamber 101 is bent 180 degrees so as to contact the electronic device D and the housing member Ha. The vapor chamber 101 may be bonded to the substrate S using an adhesive AD, similar to the example shown in FIG. 42. FIGS. 42 and 42A show an example of a vapor chamber 101 bent at a single bending line 108 (see FIGS. 44 and 45), but the present invention is not limited to this. The vapor chamber 101 may be bent at two or more bend lines 108 at different positions.

[0240] In this embodiment, as shown in FIG. 44, a vapor chamber 101 bent at a right angle along a single bending line 108 will be described as an example. The vapor chamber 101 shown in FIG. 44 is divided into a first region 105, a second region 106, and a bending region 107 located between the first region 105 and the second region 106. The bending region 107 is an example of a third region. The vapor chamber 101 is bent at a right angle in the bending region 107. The first region 105 and the second region 106 are formed substantially flat. The electronic device D may be in contact with the first region 105, and the housing member Ha (see FIG. 42) may be in contact with the second region 106. A detailed description of each region will be given later.

[0241] Here, first, the configuration of the vapor chamber 101 will be described with reference to Figures 45 to 58, which show the vapor chamber 101 before bending. The vapor chamber 101 shown in Figure 44 is obtained by bending the flat vapor chamber 101 shown in Figure 45.

[0242] 45 and 46, the vapor chamber 101 has a sealed space 103 in which working fluids 102a and 102b are sealed. The working fluids 102a and 102b in the sealed space 103 repeatedly undergo phase changes, thereby cooling the electronic device D. Examples of the working fluids 102a and 102b include pure water, ethanol, methanol, acetone, and mixtures thereof.

[0243] As shown in FIGS. 45 and 46 , the vapor chamber 101 includes a first sheet 110, a second sheet 120, a wick sheet 130 for the vapor chamber, a vapor flow path portion 150, and a liquid flow path portion 160. The second sheet 120 is provided on the opposite side of the wick sheet 130 from the first sheet 110. The wick sheet 130 for the vapor chamber is an example of a main body sheet and is interposed between the first sheet 110 and the second sheet 120. The wick sheet 130 for the vapor chamber will hereinafter be simply referred to as the wick sheet 130. In the vapor chamber 101 according to this embodiment, the first sheet 110, the wick sheet 130, and the second sheet 120 are stacked in this order. Note that, although an example in which the wick sheet 130 is formed of a single sheet is shown, the wick sheet 130 may be formed of two or more sheets, and the number of sheets in the wick sheet 130 is arbitrary.

[0244] The vapor chamber 101 shown in FIG. 45 is generally formed in the shape of a thin flat plate. The planar shape of the vapor chamber 101 before bending is arbitrary, and may be a rectangular shape as shown in FIG. 45. The planar shape of the vapor chamber 101 may be, for example, a rectangle with one side 1 cm and the other 3 cm, or a square with one side 15 cm. The planar dimensions of the vapor chamber 101 before bending are arbitrary. In this embodiment, an example will be described in which the planar shape of the vapor chamber 101 before bending is a rectangle with the X direction (described later) as the longitudinal direction. In this case, as shown in FIGS. 47 to 55, the first sheet 110, the second sheet 120, and the wick sheet 130 may have the same planar shape as the vapor chamber 101. The planar shape of the vapor chamber 101 before bending is not limited to a rectangular shape and may be any shape, such as a circular shape, an elliptical shape, an L-shape, or a T-shape.

[0245] 44 and 45, the vapor chamber 101 has an evaporation region SR where the working fluid 102b evaporates and a condensation region CR where the working vapor 102a condenses. The working vapor 102a is a working fluid in a gaseous state, and the working fluid 102b is a working fluid in a liquid state.

[0246] The evaporation region SR is a region that overlaps with the electronic device D in a planar view and is a region that comes into contact with the electronic device D. The evaporation region SR is located within the first region 105, but the position of the evaporation region SR is arbitrary. In this embodiment, the evaporation region SR is formed on one side in the X direction of the vapor chamber 101 (the left side in FIG. 45). Heat from the electronic device D is transferred to the evaporation region SR, and this heat evaporates the working fluid 102b, generating working vapor 102a. The heat from the electronic device D can be transferred not only to the region that overlaps with the electronic device D in a planar view, but also to the periphery of the region where the electronic device D overlaps. Therefore, the evaporation region SR may include the region that overlaps with the electronic device D and the periphery thereof in a planar view.

[0247] The condensation region CR is a region that does not overlap with the electronic device D in a plan view, and is a region where the working vapor 102a mainly releases heat and condenses. The condensation region CR may be located within the second region 106. The condensation region CR may be a region surrounding the evaporation region SR including the second region 106. Heat is released from the working vapor 102a in the condensation region CR. The working vapor 102a is cooled and condensed, producing the working liquid 102b.

[0248] Here, the plan view refers to the state of the vapor chamber 101 as viewed from a direction perpendicular to the surface that receives heat from the electronic device D and the surface that releases the received heat. In this embodiment, the heat-receiving surface corresponds to the second sheet outer surface 120b of the second sheet 120, which will be described later, and the heat-releasing surface corresponds to the first sheet outer surface 110a of the first sheet 110, which will be described later. Note that the heat-receiving surface may correspond to the first sheet outer surface 110a, and the heat-releasing surface may correspond to the second sheet outer surface 120b. For example, as shown in FIG. 44, in the first region 105 of the bent vapor chamber 101, the state viewed from the direction indicated by arrow V1 corresponds to the plan view. In the second region 106, the state viewed from the direction indicated by arrow V2 corresponds to the plan view. As shown in FIG. 45, in the vapor chamber 101 before bending, the state viewed from above or below corresponds to the plan view.

[0249] As shown in FIG. 46, the first sheet 110 includes a first sheet outer surface 110a located on the opposite side to the wick sheet 130, and a first sheet inner surface 110b facing the wick sheet 130. In the second region 106 described above, the first sheet outer surface 110a may be in contact with the housing member Ha described above. A first main body surface 130a of the wick sheet 130 (described below) is in contact with the first sheet inner surface 110b. As shown in FIGS. 46 and 47, the first sheet 110 may be formed in a substantially flat shape. The first sheet 110 may have a substantially constant thickness.

[0250] As shown in Fig. 47, alignment holes 112 may be formed in the four corners of the first sheet 110. Fig. 47 shows an example in which the planar shape of the alignment holes 112 is circular, but this is not limiting. The alignment holes 112 may also penetrate the first sheet 110.

[0251] As shown in FIG. 47, the second sheet 120 includes a second sheet inner surface 120a facing the wick sheet 130 and a second sheet outer surface 120b located on the opposite side from the wick sheet 130. In the first region 105 described above, the electronic device D described above may be in contact with the second sheet outer surface 120b. A second main body surface 130b of the wick sheet 130, which will be described later, is in contact with the second sheet inner surface 120a. As shown in FIGS. 46 and 48, the second sheet 120 may be formed in a substantially flat shape. The second sheet 120 may have a substantially constant thickness.

[0252] As shown in Fig. 48, alignment holes 122 may be formed in the four corners of second sheet 120. Fig. 48 shows an example in which alignment holes 122 have a circular planar shape, but this is not limiting. Alignment holes 122 may penetrate second sheet 120.

[0253] 45, 48, and 49, the second sheet 120 includes a plurality of second sheet outer surface recesses 123 located on the second sheet outer surface 120b. The second sheet outer surface recesses 123 may be located in the bending region 107, as shown in FIG.

[0254] As shown in FIGS. 45 and 48 , the second sheet outer surface recess 123 extends in a direction intersecting the X direction in plan view. The second sheet outer surface recess 123 may extend in the Y direction or along the bending line 108. The second sheet outer surface recess 123 may cross the first vapor passage 151 or the second vapor passage 152 in plan view. In the present embodiment, the second sheet outer surface recess 123 is formed over the entire Y direction of the second sheet 120. In this case, the second sheet outer surface recess 123 extends so as to intersect the frame portion 132, each land portion 133, and each vapor passage 151, 152 in plan view. However, this is not limited thereto, and the second sheet outer surface recess 123 does not have to be formed over the entire Y direction of the second sheet 120 as long as it ensures the flexibility of the vapor chamber 101 and the flow path cross-sectional area of ​​each vapor passage 151, 152 after bending. 45, the second sheet outer surface recess 123 has a linear shape extending in the Y direction in plan view, but is not limited to this. For example, as shown in Fig. 50, the second sheet outer surface recess 123 may have a rosary-like shape in plan view, with multiple circles partially overlapping each other in the Y direction. In this way, the planar shape of the second sheet outer surface recess 123 is arbitrary.

[0255] As shown in Figure 49, the second sheet outer surface recesses 123 are formed in a concave shape on the second sheet outer surface 120b. The second sheet outer surface recesses 123 may be formed in the shape of a groove extending in the Y direction. The second sheet outer surface recesses 123 may be aligned in the X direction or spaced apart at equal intervals in the X direction. The second sheet outer surface recesses 123 may be positioned parallel to each other.

[0256] The bending region 107 is a region where the vapor chamber 101 is bent. As a result, after the vapor chamber 101 is bent, the second sheet outer surface recess 123 is located in the bending region 107. The second sheet outer surface recess 123 extends along the bending line 108.

[0257] The second sheet outer surface recess 123 is formed by etching the second sheet outer surface 120b of the second sheet 120 in a second sheet etching process described below. As a result, the second sheet outer surface recess 123 may have a curved wall surface, as shown in FIG. 49. This wall surface defines the second sheet outer surface recess 123 and may be curved in a shape that bulges toward the second sheet inner surface 120a. FIG. 49 shows an example in which the second sheet outer surface recess 123 has a semicircular cross section. However, the cross-sectional shape of the second sheet outer surface recess 123 may be any shape as long as it can absorb the stress acting on the second sheet 120 when the vapor chamber 101 is bent. For example, as shown in FIG. 51, the cross-sectional shape of the second sheet outer surface recess 123 may be triangular. Furthermore, as shown in FIG. 52, the cross-sectional shape of the second sheet outer surface recess 123 may be rectangular. For example, the cross-sectional shape of the second sheet outer surface recess 123 may be trapezoidal, as shown in Fig. 53. For example, the cross-sectional shape of the second sheet outer surface recess 123 may be partially circular, with the inner width being wider than the opening, as shown in Fig. 54. The second sheet outer surface recess 123 may be formed by a method other than etching, and any method for forming the second sheet outer surface recess 123 is acceptable. For example, the second sheet outer surface recess 123 may be formed by press working or router working.

[0258] As shown in FIG. 49, the width w18 of the second sheet outer surface recess 123 may be, for example, 10 μm to 60 μm. The width w18 refers to the dimension of the second sheet outer surface recess 123 on the second sheet outer surface 120b. The width w18 corresponds to the X-direction dimension of the second sheet outer surface recess 123. The X-direction pitch p11 of the second sheet outer surface recess 123 may be, for example, 20 μm to 100 μm. The depth h12 of the second sheet outer surface recess 123 may be, for example, 5 μm to 30 μm when the thickness t13 of the second sheet 120 is approximately 35 μm. The depth h12 corresponds to the Z-direction dimension of the second sheet outer surface recess 123.

[0259] 45, the wick sheet 130 has a first main body surface 130a and a second main body surface 130b located on the opposite side to the first main body surface 130a. A first sheet inner surface 110b of the first sheet 110 contacts the first main body surface 130a. A second sheet inner surface 120a of the second sheet 120 contacts the second main body surface 130b.

[0260] The first sheet inner surface 110b of the first sheet 110 and the first main body surface 130a of the wick sheet 130 may be diffusion bonded. The first sheet inner surface 110b and the first main body surface 130a may be permanently bonded to each other.

[0261] Similarly, the second sheet inner surface 120a of the second sheet 120 and the second main body surface 130b of the wick sheet 130 may be diffusion bonded. The second sheet inner surface 120a and the second main body surface 130b may be permanently bonded to each other.

[0262] The term "permanently joined" is not limited to a strict meaning, but is used to mean that the joining is sufficient to maintain the sealing of the sealed space 103 when the vapor chamber 101 is operating.

[0263] As shown in Figures 45, 55, and 56, the wick sheet 130 according to this embodiment includes a frame portion 132 and a plurality of land portions 133. The frame portion 132 defines a vapor flow path portion 150 and is formed in a rectangular frame shape along the X and Y directions in a plan view. The land portion 133 is located inside the frame portion 132 in a plan view, and the vapor flow path portion 150 is located around the land portion 133. This allows the working vapor 102a to flow around the land portion 133. The frame portion 132 and the land portion 133 are not etched in the wick sheet etching process described below, and the material of the wick sheet 130 remains. A first steam passage 151 (described below) through which the working vapor 102a flows is formed between the frame portion 132 and adjacent land portions 133. A second steam passage 152 (described below) through which the working vapor 102a flows is formed between adjacent land portions 133.

[0264] In plan view, the land portion 133 may extend in an elongated shape with the X direction as the longitudinal direction. The planar shape of the land portion 133 may be an elongated rectangle. The X direction is an example of a first direction and corresponds to the left-right direction in Figures 55 and 56. The land portions 133 may also be arranged at equal intervals in the Y direction. The Y direction is an example of a second direction and is a direction perpendicular to the X direction in plan view. The Y direction is the width direction of the land portion 133 and corresponds to the up-down direction in Figures 55 and 56. The land portions 133 may be positioned parallel to each other. The direction perpendicular to both the X direction and the Y direction is defined as the Z direction. The Z direction corresponds to the up-down direction in Figures 46 and 57 and corresponds to the thickness direction.

[0265] 57, the width w11 of the land portion 133 may be, for example, 100 μm to 1500 μm. Here, the width w11 of the land portion 133 is the dimension of the land portion 133 in the Y direction. The width w11 means the dimension of the wick sheet 130 in the Z direction at a position where a through portion 134, which will be described later, exists.

[0266] Here, the X direction in the first region 105 and the second region 106 of the vapor chamber 101 shown in FIG. 44 corresponds to the direction along the longitudinal direction of the land portion 133. The X direction in the first region 105 corresponds to the up-and-down direction in FIG. 44. The Y direction in the first region 105 and the second region 106 of the vapor chamber 101 shown in FIG. 44 corresponds to the direction in which the land portions 133 are lined up. The Z direction in the first region 105 and the second region 106 of the vapor chamber 101 shown in FIG. 44 corresponds to the direction perpendicular to the vapor chamber 101. The Z direction in the second region 106 corresponds to the up-and-down direction in FIG. 44.

[0267] The frame body portion 132 and each land portion 133 are diffusion-bonded to the first sheet 110 and also to the second sheet 120. This improves the mechanical strength of the vapor chamber 101. Wall surfaces 153a of the first vapor flow path recess 153 and wall surfaces 154a of the second vapor flow path recess 154, which will be described later, form the side walls of the land portion 133. The first main body surface 130a and the second main body surface 130b of the wick sheet 130 may be formed flat across the frame body portion 132 and each land portion 133.

[0268] As shown in Figures 55 and 56, alignment holes 135 may be formed at the four corners of the wick sheet 130. Figures 55 and 56 show an example in which the planar shape of the alignment holes 135 is circular, but this is not limiting. The alignment holes 135 may also penetrate the wick sheet 130.

[0269] As shown in FIG. 46 , the vapor flow path portion 150 may be provided on the first main body surface 130a of the wick sheet 130. The vapor flow path portion 150 is an example of a space portion. The vapor flow path portion 150 may be a flow path through which the working vapor 102a mainly passes. The working liquid 102b may also pass through the vapor flow path portion 150. In this embodiment, the vapor flow path portion 150 may extend from the first main body surface 130a to the second main body surface 130b, or may penetrate the wick sheet 130. The vapor flow path portion 150 may be covered by the first sheet 110 on the first main body surface 130a, and may be covered by the second sheet 120 on the second main body surface 130b.

[0270] As shown in FIGS. 55 and 56 , the steam channel section 150 according to this embodiment may include a first steam channel 151 and a plurality of second steam channels 152. The first steam channel 151 and the second steam channel 152 are each an example of a working fluid channel. The first steam channel 151 is formed between a frame body section 132 and a land section 133. The first steam channel 151 is formed inside the frame body section 132 and continuously outside the land section 133. The planar shape of the first steam channel 151 may be a rectangular frame shape along the X and Y directions. The second steam channel 152 is formed between adjacent land sections 133. The planar shape of the second steam channel 152 may be an elongated rectangular shape. The plurality of lands 133 partition the steam channel section 150 into the first steam channel 151 and a plurality of second steam channels 152.

[0271] 46, the first vapor passage 151 and the second vapor passage 152 may extend from the first main body surface 130a to the second main body surface 130b of the wick sheet 130. In this case, the first vapor passage 151 and the second vapor passage 152 penetrate from the first main body surface 130a to the second main body surface 130b. The first vapor passage 151 and the second vapor passage 152 include a first vapor flow path recess 153 provided in the first main body surface 130a and a second vapor flow path recess 154 provided in the second main body surface 130b. The first vapor flow path recess 153 and the second vapor flow path recess 154 are in communication with each other.

[0272] The first vapor flow path recess 153 may be formed by etching from the first main body surface 130a of the wick sheet 130 in a wick sheet etching step described below. The first vapor flow path recess 153 is formed in a concave shape on the first main body surface 130a. As shown in FIG. 57, the first vapor flow path recess 153 may have a curved wall surface 153a. FIG. 57 shows a cross section perpendicular to the X direction. The wall surface 153a defines the first vapor flow path recess 153 and may be curved so as to approach the opposing wall surface 153a as it approaches the second main body surface 130b. The first vapor flow path recess 153 constitutes a portion of the first vapor passage 151 relatively close to the first sheet 110 and a portion of the second vapor passage 152 relatively close to the first sheet 110.

[0273] The width w12 of the first vapor flow path recess 153 in the first region 105 and the second region 106 may be, for example, 100 μm to 5000 μm. The width w12 of the first vapor flow path recess 153 is the dimension in the Y direction, and is the dimension of the first vapor flow path recess 153 on the first main body surface 130a. The width w12 corresponds to the dimension in the Y direction of the portion of the first vapor path 151 extending in the X direction and the dimension in the Y direction of the second vapor path 152. The width w12 also corresponds to the dimension in the X direction of the portion of the first vapor path 151 extending in the Y direction.

[0274] The second vapor flow path recess 154 may be formed by etching from the second main body surface 130b of the wick sheet 130 in a wick sheet etching step described below. The second vapor flow path recess 154 is formed in a concave shape on the second main body surface 130b. As shown in FIG. 57, the second vapor flow path recess 154 may have a curved wall surface 154a. This wall surface 154a defines the second vapor flow path recess 154 and may be curved so as to approach the opposing wall surface 154a as it approaches the first main body surface 130a. The second vapor flow path recess 154 constitutes a portion of the first steam passage 151 relatively close to the second sheet 120 and a portion of the second steam passage 152 relatively close to the second sheet 120.

[0275] The width w13 of the second vapor flow path recess 154 in the first region 105 and the second region 106 may be, for example, 100 μm to 5000 μm, similar to the width w12 of the first vapor flow path recess 153 described above. The width w13 of the second vapor flow path recess 154 is the dimension in the Y direction, and is the dimension of the second vapor flow path recess 154 on the second main body surface 130b. The width w13 corresponds to the dimension in the Y direction of the portion of the first steam path 151 extending in the X direction and the dimension in the Y direction of the second steam path 152. The width w13 also corresponds to the dimension in the X direction of the portion of the first steam path 151 extending in the Y direction. The width w13 of the second vapor flow path recess 154 may be equal to or different from the width w12 of the first vapor flow path recess 153.

[0276] As shown in FIG. 57 , a wall surface 153 a of the first steam flow path recess 153 and a wall surface 154 a of the second steam flow path recess 154 may be connected to form a through-portion 134. In this embodiment, the planar shape of the through-portion 134 in the first steam path 151 may be a rectangular frame shape. The planar shape of the through-portion 134 in the second steam path 152 may be an elongated rectangular shape. The through-portion 134 may be defined by a ridge line formed by the joining of the wall surface 153 a of the first steam flow path recess 153 and the wall surface 154 a of the second steam flow path recess 154. As shown in FIG. 57 , the ridge line may be formed to protrude inward of the steam paths 151, 152. The planar area of ​​the first steam path 151 at the through-portion 134 may be minimized, and the planar area of ​​the second steam path 152 at the through-portion 134 may be minimized. The width w14 of the through portion 134 of each of the steam passages 151, 152 may be, for example, 400 μm to 5000 μm. Here, the width w14 of the through portion 134 is the width of the through portion 134 in the first region 105 and the second region 106, and corresponds to the gap between the land portions 133 adjacent to each other in the Y direction. The width w14 may be the gap between the portions of the land portions 133 that protrude most inward of the steam passages 151, 152, as shown in FIG.

[0277] The position of the through portion 134 in the Z direction may be an intermediate position between the first main body surface 130a and the second main body surface 130b. Alternatively, the position of the through portion 134 may be a position closer to the first sheet 110 than the intermediate position, or a position closer to the second sheet 120 than the intermediate position. The position of the through portion 134 in the Z direction is arbitrary.

[0278] In the present embodiment, as described above, the cross-sectional shapes of first steam passage 151 and second steam passage 152 are formed to include through-holes 134 defined by ridgelines formed to protrude inward, but this is not limited to this. For example, the cross-sectional shapes of first steam passage 151 and second steam passage 152 may be trapezoidal, parallelogram-shaped, or barrel-shaped.

[0279] The steam flow path section 150 including the first steam path 151 and the second steam path 152 configured in this manner constitutes a part of the above-mentioned sealed space 103. Each of the steam paths 151, 152 has a relatively large flow path cross-sectional area so that the working steam 102a can pass through.

[0280] 57, for clarity of the drawing, the first steam passage 151 and the second steam passage 152 are enlarged and shown. The number of main grooves 161, which will be described later, is different from that in FIG.

[0281] Although not shown, a plurality of support portions may be provided within each of the steam passages 151 and 152 to support the land portion 133 on the frame portion 132. Support portions may also be provided to support adjacent land portions 133. These support portions may be provided on both sides of the land portion 133 in the X direction or on both sides of the land portion 133 in the Y direction. The support portions may be formed so as not to impede the flow of the working steam 102a diffusing through the steam passage portion 150. For example, the support portions may be located near one of the first main body surface 130a and the second main body surface 130b of the wick sheet 130, and a space forming the steam passage portion 150 may be formed near the other. This allows the thickness of the support portions to be thinner than the thickness of the wick sheet 130, preventing the first steam passage 151 and the second steam passage 152 from being separated in the X direction and the Y direction.

[0282] As shown in FIG. 45, the vapor chamber 101 may include an injection part 104 that injects the working fluid 102b into the sealed space 103. The injection part 104 includes an injection passage 136 that communicates with the first vapor passage 151. The position of the injection part 104 is arbitrary. As shown in FIGS. 55 and 56, the injection passage 136 may be formed in a concave shape in the second main body surface 130b. Alternatively, the injection passage 136 may be formed in a concave shape in the first main body surface 130a. Depending on the configuration of the liquid flow path section 160 , the injection flow path 136 may be in communication with the liquid flow path section 160 .

[0283] As shown in FIGS. 46, 55, and 57, the liquid flow path portion 160 may be formed between the first sheet 110 and the wick sheet 130. In this embodiment, the liquid flow path portion 160 is formed on the first main body surface 130a of each land portion 133. The liquid flow path portion 160 may be a flow path through which mainly the working liquid 102b passes. The working vapor 102a may also pass through the liquid flow path portion 160. The liquid flow path portion 160 forms part of the sealed space 103 and communicates with the vapor flow path portion 150. The liquid flow path portion 160 is configured as a capillary structure for transporting the working liquid 102b to the evaporation region SR. The liquid flow path portion 160 may also be referred to as a wick. The liquid flow path portion 160 may be formed over the entire first main body surface 130a of each land portion 133. 55 etc., the liquid flow path portion 160 may be formed on the inner side of the first main body surface 130a of the frame body portion 132. In the present embodiment, the liquid flow path portion is not formed on the second main body surface 130b of the land portion 133 and the second main body surface 130b of the frame body portion 132.

[0284] As shown in FIG. 58, the liquid flow path section 160 is an example of a first groove assembly including a plurality of grooves. More specifically, the liquid flow path section 160 includes a plurality of main flow grooves 161 and a plurality of communication grooves 165. The main flow grooves 161 and communication grooves 165 of the liquid flow path section 160 are an example of a first groove. The main flow grooves 161 and communication grooves 165 are grooves through which the working fluid 102b passes. The communication grooves 165 communicate with the main flow grooves 161.

[0285] As shown in FIG. 58, each of the main grooves 161 extends in the X direction. The main grooves 161 have a small flow path cross-sectional area so that the working fluid 102b flows mainly by capillary action. The flow path cross-sectional area of ​​the main grooves 161 is smaller than the flow path cross-sectional area of ​​the vapor passages 151, 152. The main grooves 161 are configured to transport the working fluid 102b condensed from the working vapor 102a to the evaporation region SR. The main grooves 161 may be spaced apart at equal intervals along the Y direction perpendicular to the X direction. The main grooves 161 may be positioned parallel to each other.

[0286] The main groove 161 is formed by etching from the first main body surface 130a of the wick sheet 130 in a wick sheet etching step described below. As a result, the main groove 161 may have a wall surface 162 formed in a curved shape, as shown in Fig. 57. This wall surface 162 defines the main groove 161 and may be curved in a shape that bulges toward the second main body surface 130b.

[0287] As shown in FIGS. 57 and 58, the width w15 of the mainstream groove 161 may be smaller than the width w12 of the first steam flow path recess 153. The width w15 of the mainstream groove 161 may be smaller than the width w11 of the land portion 133. The width w15 of the mainstream groove 161 may be, for example, 5 μm to 400 μm. The width w15 refers to the dimension of the mainstream groove 161 in the first main body surface 130a. In FIGS. 57 and 58, the width w15 corresponds to the dimension of the mainstream groove 161 in the Y direction. The depth h11 of the mainstream groove 161 may be, for example, 3 μm to 300 μm. The depth h11 corresponds to the dimension of the mainstream groove 161 in the Z direction.

[0288] As shown in Figure 58, each communication groove 165 extends in a direction different from the X direction. According to this embodiment, each communication groove 165 extends in the Y direction and is formed perpendicular to the mainstream grooves 161. Some communication grooves 165 connect adjacent mainstream grooves 161 to each other. Other communication grooves 165 connect the first steam passage 151 or the second steam passage 152 to the mainstream groove 161. That is, the communication groove 165 extends from the side edge 133e of the land portion 133 in the Y direction to the mainstream groove 161 adjacent to the side edge 133e. In this way, the first steam passage 151 communicates with the mainstream groove 161, and the second steam passage 152 communicates with the mainstream groove 161.

[0289] The communication groove 165 has a small flow path cross-sectional area so that the working fluid 102b flows mainly by capillary action. The flow path cross-sectional area of ​​the communication groove 165 is smaller than the flow path cross-sectional area of ​​the steam passages 151, 152. The communication grooves 165 are spaced apart at predetermined intervals along the X direction. The communication grooves 165 may be positioned parallel to one another.

[0290] Like the mainstream grooves 161, the communication grooves 165 are also formed by etching, which will be described later. Thus, the communication grooves 165 may have wall surfaces (not shown) formed in a curved shape similar to the mainstream grooves 161. The width w16 of the communication grooves 165 may be smaller than the width w12 of the first steam flow path recess 153. The width w16 of the communication grooves 165 may be smaller than the width w11 of the land portions 133. As shown in FIG. 58, the width w16 of the communication grooves 165 may be equal to the width w15 of the mainstream grooves 161. However, the width w16 may be larger or smaller than the width w15. The width w16 refers to the dimension of the communication groove 165 in the first body surface 130a. In FIG. 58, the width w16 corresponds to the dimension of the communication groove 165 in the X direction. The depth of the communication groove 165 may be equal to the depth h11 of the mainstream grooves 161. However, the depth of the connecting groove 165 may be deeper or shallower than the depth h11.

[0291] As shown in Figure 58, the liquid flow path section 160 has a plurality of convex portion rows 163. The convex portion rows 163 are formed on the first main body surface 130a of each land portion 133. The convex portion rows 163 are located between adjacent main flow grooves 161. Each convex portion row 163 includes a plurality of convex portions 164 arranged in the X direction. The convex portions 164 abut against the first sheet 110. As shown in Fig. 58, each protrusion 164 is formed in a rectangular shape in plan view with the X direction as its longitudinal direction. A main groove 161 is interposed between protrusions 164 adjacent to each other in the Y direction. A communication groove 165 is interposed between protrusions 164 adjacent to each other in the X direction.

[0292] The protrusions 164 are portions that are not etched in the wick sheet etching step described below, and the material of the wick sheet 130 remains. In this embodiment, the planar shape of the protrusions 164 is rectangular, as shown in Fig. 58. More specifically, the planar shape of the protrusions 164 corresponds to the planar shape at the position of the first main body surface 130a.

[0293] In this embodiment, the protrusions 164 are positioned in a staggered manner. More specifically, the protrusions 164 of the protrusion rows 163 adjacent to each other in the Y direction are positioned at positions offset from each other in the X direction. This offset may be half the arrangement pitch of the protrusions 164 in the X direction. The width w17 of the protrusions 164 may be, for example, 5 μm to 500 μm. The width w17 refers to the dimension of the protrusions 164 on the first main body surface 130a. In FIG. 58, the width w17 corresponds to the dimension of the protrusions 164 in the Y direction. Note that the positions of the protrusions 164 are not limited to a staggered arrangement, and they may be arranged in parallel. In this case, the protrusions 164 of the protrusion rows 163 adjacent to each other in the Y direction are positioned at the same position in the X direction.

[0294] The materials constituting the first sheet 110, the second sheet 120, and the wick sheet 130 are not particularly limited as long as they have sufficient thermal conductivity to ensure the heat dissipation efficiency of the vapor chamber 101. For example, each of the sheets 110, 120, and 130 may be made of a metal material. For example, each of the sheets 110, 120, and 130 may contain copper or a copper alloy. Copper and copper alloys have good thermal conductivity and corrosion resistance when pure water is used as the working fluid. Examples of copper include pure copper and oxygen-free copper (C1020). Examples of copper alloys include copper alloys containing tin, copper alloys containing titanium (C1990, etc.), and Corson copper alloys (C7025, etc.), which are copper alloys containing nickel, silicon, and magnesium. An example of a copper alloy containing tin is phosphor bronze (C5210, etc.).

[0295] The thickness t11 of the vapor chamber 101 shown in FIG. 46 may be, for example, 100 μm to 500 μm. By making the thickness t11 of the vapor chamber 101 100 μm or more, the vapor channel portion 150 can be properly secured. This allows the vapor chamber 101 to function properly. On the other hand, by making the thickness t11 500 μm or less, the thickness t11 of the vapor chamber 101 can be prevented from becoming too thick. This allows the vapor chamber 101 to be made thin.

[0296] The thickness of the wick sheet 130 may be greater than the thickness of the first sheet 110. Similarly, the thickness of the wick sheet 130 may be greater than the thickness of the second sheet 120. In this embodiment, an example is shown in which the thickness of the first sheet 110 and the thickness of the second sheet 120 are equal. However, this is not limiting, and the thickness of the first sheet 110 and the thickness of the second sheet 120 may be different.

[0297] The thickness t12 of the first sheet 110 may be, for example, 6 μm to 100 μm. By setting the thickness t12 of the first sheet 110 to 6 μm or more, the mechanical strength and long-term reliability of the first sheet 110 can be ensured. On the other hand, by setting the thickness t12 of the first sheet 110 to 100 μm or less, an increase in the thickness t11 of the vapor chamber 101 can be prevented. The thickness t13 of the second sheet 120 may be set to the same value as the thickness t12 of the first sheet 110.

[0298] The thickness t14 of the wick sheet 130 may be, for example, 50 μm to 400 μm. By making the thickness t14 of the wick sheet 130 50 μm or more, the vapor channel portion 150 can be properly secured. This allows the vapor chamber 101 to function properly. On the other hand, by making the thickness t14 of the wick sheet 130 400 μm or less, the thickness t11 of the vapor chamber 101 can be prevented from becoming too thick. This allows the vapor chamber 101 to be made thinner. The thickness t14 of the wick sheet 130 may be the distance between the first main body surface 130a and the second main body surface 130b.

[0299] As shown in FIG. 45 , vapor chamber 101 according to this embodiment includes a bending region 107. In bending region 107, vapor chamber 101 is bent along bending line 108 that extends in a direction intersecting the X direction in a plan view. As shown in FIGS. 44 and 45 , bending line 108 according to this embodiment extends in the Y direction in a plan view. The Y direction is a direction perpendicular to the X direction in a plan view. Bending line 108 crosses frame portion 132, land portion 133, first steam passage 151, and second steam passage 152. This prevents deformation of first sheet 110, such as intrusion into each of steam passages 151 and 152, and prevents deformation of second sheet 120, such as intrusion into each of steam passages 151 and 152. The flow path cross-sectional areas of first steam passage 151 and second steam passage 152 can be secured. The first region 105, the second region 106, and the curved region 107 may be separated by a boundary line along the curved line 108. In the example shown in Figures 44 and 45, each of the regions 105, 106, and 107 may be separated by a boundary line extending in the Y direction in a plan view.

[0300] 45 and 59, the second sheet outer surface recess 123 is located in the bending region 107. The second sheet outer surface recess 123 overlaps the bending line 108 when the bending region 107 is viewed from the inside or outside of the bend.

[0301] The vapor chamber 101 is bent as shown in FIG. 59. The first sheet 110 is located on the outer side of the bend than the wick sheet 130. In the bent region 107, the first sheet 110 is located on the outer side of the bend than the wick sheet 130 with respect to the center O of the bend. The second sheet 120 is located on the inner side of the bend than the wick sheet 130. The second sheet 120 is located on the inner side of the bend than the wick sheet 130 with respect to the center O of the bend.

[0302] Each steam passage 151, 152 may include a passage bend 157 located in the bend region 107, as shown in Figure 59. Figure 59 shows an example of a passage bend 157. 59, the shape of the passage bend portion 157 when viewed along the Y direction forms a quarter arc, but is not limited to this. The passage bend portion 157 may include the first steam flow path recess 153 and the second steam flow path recess 154 described above.

[0303] Next, a method for manufacturing the vapor chamber 101 of this embodiment having such a configuration will be described.

[0304] First, in a preparation step, the first sheet 110, the second sheet 120, and the wick sheet 130 are prepared. The preparation step may include a second sheet etching step in which the second sheet 120 is formed by etching, and a wick sheet etching step in which the wick sheet 130 is formed by etching. In each etching step, the second sheet 120 and the wick sheet 130 may be formed by etching using a patterned resist film (not shown) formed by photolithography technology.

[0305] In the temporary joining step, the first sheet 110, the wick sheet 130, and the second sheet 120 are temporarily joined together. For example, the sheets 110, 120, and 130 may be temporarily joined together by spot welding or laser welding. At this time, the sheets 110, 120, and 130 may be aligned using the alignment holes 112, 122, and 135 described above.

[0306] Next, in a bonding step, the first sheet 110, the wick sheet 130, and the second sheet 120 are permanently bonded together. The sheets 110, 120, and 130 may be bonded together by diffusion bonding.

[0307] After the joining step, the sealed space 103 is evacuated as a filling step, and the hydraulic fluid 102b is filled into the sealed space 103 from the filling portion 104 (see FIG. 45).

[0308] After the injection step, the above-mentioned injection flow path 136 is sealed in the sealing step. This blocks communication between the sealed space 103 and the outside, sealing the sealed space 103. The sealed space 103 is filled with the working fluid 102b, and the working fluid 102b in the sealed space 103 is prevented from leaking to the outside.

[0309] After the sealing process, the first sheet 110, the second sheet 120, and the wick sheet 130 may be bent in a bending process. For example, the sheets 110, 120, and 130 are bent along a bending line 108 extending in the Y direction as shown in FIG. 45. At this time, a jig (not shown) is abutted against the second sheet outer surface 120b of the second sheet 120, which is the inner side of the bend. Both ends of the sheets 110, 120, and 130 in the X direction are gripped, and the sheets 110, 120, and 130 are bent at a desired angle. This results in the bent vapor chamber 101 shown in FIG. 44, and the bent region 107 of the vapor chamber 101 is formed. The bending process may be performed between the joining process and the injection process.

[0310] In this embodiment, a second sheet outer surface recess 123 is formed on the second sheet outer surface 120b of the second sheet 120 located on the inside of the bend. In the bending process, the vapor chamber 101 may be bent at the position where the second sheet outer surface recess 123 is formed. The vapor chamber 101 may be bent so that the bending line 108 is aligned with the direction in which the second sheet outer surface recess 123 extends. The second sheet outer surface recess 123 is easily visible and can serve as a marker for the bending position.

[0311] When the second sheet 120 is bent, a compressive stress acts on the second sheet lid portion 124 (see FIG. 57) that covers the steam passages 151, 152 of the second sheet 120. Since the second sheet 120 is located on the inner side of the bend, a jig (not shown) abuts against the second sheet outer surface 120b of the second sheet 120. As a result, displacement of the second sheet lid portion 124 toward the inside of the bend is restricted, and the second sheet lid portion 124 tends to enter the second steam flow path recess 154, which is located on the outside of the bend relative to the second sheet 120. However, according to the present embodiment, a second sheet outer surface recess 123 is formed on the second sheet outer surface 120b in the bent region 107. This makes it possible to absorb the compressive stress acting on the second sheet lid portion 124 when bent, and to prevent the second sheet lid portion 124 from entering the second steam flow path recess 154.

[0312] In this manner, the vapor chamber 101 according to this embodiment is obtained.

[0313] When mounting the vapor chamber 101 obtained as described above on a substrate S, it may be bonded to the substrate S using an adhesive AD, as shown in FIG. 59. The adhesive AD may be bonded to the second sheet outer surface 120b in the curved region 107. In this case, the adhesive AD penetrates into the second sheet outer surface recess 123. This improves the adhesion between the vapor chamber 101 and the adhesive AD.

[0314] Next, a method for operating the vapor chamber 101, that is, a method for cooling the electronic device D, will be described.

[0315] The vapor chamber 101 obtained as described above is installed in a housing H of a mobile terminal or the like. In the second region 106, the first sheet outer surface 110a of the first sheet 110 contacts the housing member Ha. In the first region 105, the second sheet outer surface 120b of the second sheet 120 contacts the electronic device D. The working liquid 102b in the sealed space 103 adheres to the wall surfaces of the sealed space 103 due to its surface tension. More specifically, the working liquid 102b adheres to the wall surfaces 153a of the first vapor flow path recess 153, the wall surfaces 154a of the second vapor flow path recess 154, the wall surfaces 162 of the main groove 161 of the liquid flow path section 160, and the wall surfaces of the connecting groove 165. The working liquid 102b may also adhere to a portion of the first sheet inner surface 110b of the first sheet 110 exposed to the first vapor flow path recess 153. Furthermore, the working fluid 102b may also adhere to the portions of the second sheet inner surface 120a of the second sheet 120 that are exposed to the second vapor flow path recess 154, the main groove 161, and the communication groove 165.

[0316] In this state, when the electronic device D generates heat, the working fluid 102b present in the evaporation region SR receives the heat from the electronic device D. The received heat is absorbed as latent heat, causing the working fluid 102b to evaporate and generate working vapor 102a. The generated working vapor 102a diffuses within the first vapor passage 151 and the second vapor passage 152 that constitute the sealed space 103 (see the solid arrows in FIG. 55). More specifically, in the portion of the first vapor passage 151 of the vapor flow path section 150 that extends in the X direction and in the second vapor passage 152, the working vapor 102a diffuses mainly in the X direction. In this case, a portion of the working vapor 102a diffuses through the passage bend portion 157. On the other hand, in the portion of the first vapor passage 151 that extends in the Y direction, the working vapor 102a diffuses mainly in the Y direction.

[0317] Then, the working steam 102a in each steam passage 151, 152 leaves the evaporation region SR and is transported to the condensation region CR, which has a relatively low temperature. In the condensation region CR, the working steam 102a is cooled by dissipating heat mainly to the first sheet 110. The heat received by the first sheet 110 from the working steam 102a is transferred to the outside air via the housing member Ha (see FIG. 46).

[0318] The working vapor 102a dissipates heat to the first sheet 110 in the condensation region CR, thereby losing the latent heat absorbed in the evaporation region SR. As a result, the working vapor 102a condenses, and working liquid 102b is generated. The generated working liquid 102b adheres to the wall surfaces 153a, 154a of each vapor flow path recess 153, 154, the first sheet inner surface 110b of the first sheet 110, and the second sheet inner surface 120a of the second sheet 120. Here, the working liquid 102b continues to evaporate in the evaporation region SR. Therefore, the working liquid 102b in the condensation region CR of the liquid flow path section 160 is transported toward the evaporation region SR by the capillary action of each mainstream groove 161 (see the dashed arrows in Figure 55). As a result, the working fluid 102b adhering to each of the wall surfaces 153a, 154a, the first sheet inner surface 110b, and the second sheet inner surface 120a moves to the liquid flow path portion 160 and enters the main groove 161 through the communication groove 165. In this way, each of the main grooves 161 and each of the communication grooves 165 is filled with the working fluid 102b. The filled working fluid 102b obtains a driving force toward the evaporation region SR due to the capillary action of each of the main grooves 161, and is smoothly transported toward the evaporation region SR. As shown in FIG. 44, even when the evaporation region SR is located above the vapor chamber 101, the working fluid 102b is transported by capillary action.

[0319] In the liquid flow path section 160, each mainstream groove 161 communicates with the adjacent other mainstream groove 161 via the corresponding communication groove 165. This allows the working fluid 102b to flow between the adjacent mainstream grooves 161, preventing the occurrence of dryout in the mainstream grooves 161. As a result, capillary action is imparted to the working fluid 102b in each mainstream groove 161, and the working fluid 102b is smoothly transported toward the evaporation region SR.

[0320] The working fluid 102b that has reached the evaporation region SR is again heated by the electronic device D and evaporates. The working vapor 102a that has evaporated from the working fluid 102b passes through the communication groove 165 in the evaporation region SR and moves to the first vapor flow path recess 153 and the second vapor flow path recess 154, which have a large flow path cross-sectional area. The working vapor 102a then diffuses within each of the vapor flow path recesses 153 and 154, and some of the working vapor 102a can diffuse through the bent path portion 157. In this way, the working fluids 102a and 102b circulate within the sealed space 103 while repeatedly changing phases, i.e., evaporating and condensing. This diffuses and releases the heat from the electronic device D. As a result, the electronic device D is cooled.

[0321] As described above, according to this embodiment, the second sheet outer surface recess 123 is located on the second sheet outer surface 120b of the second sheet 120 in the bending region 107. This allows the stress acting on the second sheet 120 to be absorbed when the vapor chamber 101 is bent, and prevents the second sheet 120 in the bending region 107 from entering the first vapor passage 151 or the second vapor passage 152. This ensures sufficient flow path cross-sectional area for the first vapor passage 151 and the second vapor passage 152, and prevents the flow of the working vapor 102a in the bending region 107 from being obstructed. As a result, the heat dissipation efficiency of the vapor chamber 101 can be improved even when the vapor chamber 101 is bent. Furthermore, because the second sheet outer surface recess 123 is easily visible, it can be used as a marker for the bending position of the vapor chamber 101 before bending. This improves the ease of bending.

[0322] Furthermore, according to this embodiment, second sheet 120 is located on the inner side of the bend relative to wick sheet 130. This allows second sheet outer surface recess 123 to absorb the compressive stress acting on second sheet 120 when vapor chamber 101 is bent. This prevents second sheet 120 in bent region 107 from entering first vapor passage 151 or second vapor passage 152.

[0323] Furthermore, according to this embodiment, second sheet outer surface recess 123 extends along bending line 108 and crosses first vapor passage 151 or second vapor passage 152. This effectively absorbs stress acting on second sheet 120 when vapor chamber 101 is bent, and further prevents second sheet 120 in bending region 107 from entering first vapor passage 151 or second vapor passage 152. Furthermore, vapor chamber 101 can be easily bent along bending line 108.

[0324] Furthermore, according to this embodiment, multiple second sheet outer surface recesses 123 are located on second sheet outer surface 120b in bending region 107. Multiple second sheet outer surface recesses 123 are aligned in the X direction. This effectively absorbs stress acting on second sheet 120 when vapor chamber 101 is bent, further preventing second sheet 120 from entering first vapor passage 151 or second vapor passage 152. Furthermore, vapor chamber 101 can be easily bent along bending line 108.

[0325] Furthermore, according to this embodiment, the bending line 108 extends in the Y direction, which is perpendicular to the X direction. This makes it easy to bend the vapor chamber 101 along the direction perpendicular to the X direction along which the land portion 133 extends. Therefore, in the bending region 107, deformation of the first sheet 110 into the steam passages 151 and 152 can be suppressed, and deformation of the second sheet 120 into the steam passages 151 and 152 can be suppressed. Therefore, the flow path cross-sectional areas of the first steam passage 151 and the second steam passage 152 can be secured, and obstruction of the flow of the working steam 102a in the bending region 107 can be suppressed.

[0326] In the above-described embodiment, an example has been described in which a liquid flow path portion is not formed on the second main body surface 130b of the land portion 133 and the second main body surface 130b of the frame portion 132. However, this is not limited to this. For example, a liquid flow path portion (not shown) may be formed on the second main body surface 130b of the land portion 133. The liquid flow path portion may include a main groove 161 and a communication groove 165, similar to the liquid flow path portion 160 described above. The flow path cross-sectional area of ​​the groove of the liquid flow path portion formed on the second main body surface 130b may be equal to or larger than the flow path cross-sectional area of ​​the groove of the liquid flow path portion 160. Furthermore, when a liquid flow path portion is formed on the second main body surface 130b, the liquid flow path portion 160 does not have to be formed on the first main body surface 130a.

[0327] In the above-described embodiment, an example has been described in which the second sheet outer surface recesses 123 extend in the Y direction. However, this is not limited to this. For example, as shown in FIG. 60, the multiple second sheet outer surface recesses 123 may be aligned along the bending line 108 or may be aligned in the Y direction. Adjacent second sheet outer surface recesses 123 are spaced apart. In the example shown in FIG. 60, the second sheet outer surface recesses 123 are arranged in a staggered pattern, but they may also be arranged in a grid pattern (see FIG. 63), and the arrangement of the second sheet outer surface recesses 123 is arbitrary.

[0328] Of the multiple second sheet outer surface recesses 123, some of the second sheet outer surface recesses 123 may overlap the first steam passage 151 or the second steam passage 152 in a plan view. The remaining second sheet outer surface recesses 123 may not overlap the first steam passage 151 or the second steam passage 152 in a plan view. Alternatively, all of the second sheet outer surface recesses 123 may overlap the first steam passage 151 or the second steam passage 152 in a plan view. In the example shown in FIG. 60 , the second sheet outer surface recesses 123 overlap the land portion 133, the frame portion 132, and the steam passages 151, 152.

[0329] 60, when vapor chamber 101 is bent, the stress acting on second sheet 120 can be absorbed, and second sheet 120 in bending region 107 can be prevented from entering first vapor passage 151 or second vapor passage 152. Furthermore, in the example shown in FIG. 60, adjacent second sheet outer surface recesses 123 are spaced apart, so that the mechanical strength of vapor chamber 101 can be prevented from decreasing in a specific direction.

[0330] In the example shown in FIG. 60 , the second sheet outer surface recess 123 has a circular planar shape, but the planar shape of the second sheet outer surface recess 123 is arbitrary. For example, as shown in FIG. 61 , the second sheet outer surface recess 123 may have an elliptical planar shape. Furthermore, as shown in FIG. 62 , the second sheet outer surface recess 123 may have a rectangular planar shape. Furthermore, as shown in FIG. 63 , when the second sheet outer surface recess 123 has a rectangular planar shape, the second sheet outer surface recess 123 may be arranged so that each side of the rectangle is inclined with respect to the X and Y directions and opposing corners of the rectangle are aligned along the bending line 108. In the example shown in FIG. 63 , the second sheet outer surface recess 123 is arranged in a lattice pattern. Furthermore, the second sheet outer surface recess 123 and the bending line 108 may extend in a direction inclined with respect to the X direction in a plan view.

[0331] Furthermore, in the above-described embodiment, an example has been described in which the second sheet outer surface recess 123 is located on the second sheet outer surface 120b of the second sheet 120 in the bending region 107. However, this is not limited to this. For example, as shown in FIG. 64 , the first sheet outer surface recess 113 may be located on the first sheet outer surface 110a of the first sheet 110 in the bending region 107. In this case, when the vapor chamber 101 is bent, the tensile stress acting on the first sheet 110 can be absorbed, and the first sheet 110 in the bending region 107 can be prevented from entering the first steam passage 151 or the second steam passage 152.

[0332] The first sheet outer surface recess 113 can be formed in the same manner as the second sheet outer surface recess 123. As shown in FIG. 64, the first sheet outer surface recess 113 may be formed on the first sheet outer surface 110a, and the second sheet outer surface recess 123 may be formed on the second sheet outer surface 120b. Alternatively, although not shown, the first sheet outer surface recess 113 may be formed on the first sheet outer surface 110a, and the second sheet outer surface recess 123 may not be formed on the second sheet outer surface 120b. Furthermore, the second sheet 120 having the second sheet outer surface recess 123 formed thereon may be disposed on the outer side of the bend, and the first sheet 110 having no first sheet outer surface recess 113 formed thereon may be disposed on the inner side of the bend.

[0333] Furthermore, in the present embodiment described above, as shown in Fig. 65 and Fig. 66, seat grooves 70, 80 as described in the first to fourteenth embodiments may be provided. In the example shown in Fig. 65 and Fig. 66, the seat groove 70 is provided in the second sheet inner surface 120a of the second sheet 120. As shown in Fig. 65 and Fig. 66, the seat groove 70 may be provided at a position overlapping with the steam passages 151, 152 and the second sheet outer surface recess 123 in plan view. The seat groove 70 does not have to be provided at a position not overlapping with the steam passages 151, 152 in plan view, for example, at a position not overlapping with the land portion 133. In the example shown in Figure 65, the first end 71 of the seat groove 70 overlaps with the edge of the land portion 133 on the negative Y-direction side (the lower side in Figure 65) when viewed in a plane, and the second end 72 of the seat groove 70 overlaps with the edge of the land portion 133 on the positive Y-direction side (the upper side in Figure 65) when viewed in a plane. 65, the seat groove 70 does not have to be provided in a position that does not overlap the second seat outer surface recess 123 in a plan view. Such a seat groove 70 can further absorb the stress acting on the second seat 120 when the vapor chamber 101 is bent, and can further prevent the second seat 120 in the bending region 107 from entering the first steam passage 151 or the second steam passage 152.

[0334] 65 and 66, the seat groove 70 is not provided in a position that does not overlap with the second seat outer surface recess 123 in a plan view, but the seat groove 70 may also be provided in a position that does not overlap with the second seat outer surface recess 123 in a plan view. In this case, since the working vapor 102a is likely to condense and the working liquid 102b is likely to be generated in the curved region 107, the condensed working liquid 102b can be quickly moved to the liquid flow path portion 160 by the capillary action of the seat groove 70, and an increase in flow path resistance can be further suppressed.

[0335] (16th embodiment) Next, a vapor chamber and an electronic device according to a sixteenth embodiment of the present disclosure will be described with reference to FIGS.

[0336] The sixteenth embodiment shown in Figures 67 and 68 differs mainly in that the bending lines extend in a direction inclined toward the first direction. The other configurations are substantially the same as those of the fifteenth embodiment shown in Figures 42 to 66. In Figures 67 and 68, the same parts as those of the fifteenth embodiment shown in Figures 42 to 66 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0337] As shown in Figures 67 and 68, the vapor chamber 101 according to this embodiment is bent along a bending line 108 that is inclined in the X direction in a plan view. The bending line 108 shown in Figures 67 and 68 extends in a direction that is inclined in the X direction and in a direction that is inclined in the Y direction. The bending line 108 according to this embodiment also extends in a direction that intersects with the X direction in a plan view.

[0338] 68, each of the second sheet outer surface recesses 123 extends in a direction inclined toward the X direction in a plan view. Even in this case, the second sheet outer surface recesses 123 intersect with the X direction. The second sheet outer surface recesses 123 may be aligned in the X direction or spaced apart at equal intervals in the X direction. The second sheet outer surface recesses 123 may be positioned parallel to each other.

[0339] As described above, according to the present embodiment, bending line 108 extends in a direction inclined toward the X direction. This prevents second sheet 120 in bending region 107 from entering first vapor passage 151 or second vapor passage 152, even when vapor chamber 101 is bent along bending line 108 that extends in a direction inclined toward the X direction. This ensures that the flow path cross-sectional areas of first vapor passage 151 and second vapor passage 152 are sufficient, and prevents the flow of working vapor 102a in bending region 107 from being obstructed. As a result, the heat dissipation efficiency of vapor chamber 101 can be improved even when the vapor chamber 101 is bent.

[0340] In the above-described embodiment, an example has been described in which the second sheet outer surface recesses 123 extend in a direction inclined toward the X direction in a plan view. However, this is not limited to this. For example, the multiple second sheet outer surface recesses 123 may be aligned along the bending line 108, or may be aligned in a direction inclined toward the X direction. In this case, the second sheet outer surface recesses 123 may be formed in the same manner as in the examples shown in Figures 60 to 63.

[0341] (17th embodiment) Next, a vapor chamber and an electronic device according to a seventeenth embodiment of the present disclosure will be described with reference to FIGS.

[0342] The seventeenth embodiment shown in Figures 69 and 70 differs mainly in that the land recesses are located on the first or second main body surface of the land portion. The other configurations are substantially the same as those of the fifteenth embodiment shown in Figures 42 to 66. In Figures 69 and 70, the same parts as those of the fifteenth embodiment shown in Figures 42 to 66 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0343] As shown in FIG. 69 , in the vapor chamber 101 according to the present embodiment, a land recess 137 is formed in the second main body surface 130b of the land portion 133. The land recess 137 does not communicate with the vapor passages 151 and 152. The land recess 137 also does not communicate with the main groove 161 and the communication groove 165 of the liquid flow path portion 160. As described above, the liquid flow path portion 160 is located on the first main body surface 130a of the land portion 133, and the land recess 137 is formed in the second main body surface 130b located opposite the liquid flow path portion 160. The liquid flow path portion 160 may be formed in one of the first main body surface 130a and the second main body surface 130b of the land portion 133, and the land recess 137 may be formed in the other. For example, when the liquid flow path portion 160 is located on the second main body surface 130b of the land portion 133, the land recess 137 may be formed in the first main body surface 130a of the land portion 133.

[0344] 70, the land recess 137 overlaps the second sheet outer surface recess 123 in a plan view. In other words, the land recess 137 overlaps the second sheet outer surface recess 123 when the bent region 107 is viewed from the inside or outside of the bend.

[0345] The land recess 137 is located in the bending region 107. The land recess 137 is formed in a concave shape in the second main body surface 130b, and may be formed in a groove shape.

[0346] The land recess 137 extends in the X direction. The land recess 137 intersects with the second sheet outer surface recess 123. The land recess 137 may extend further out than the second sheet outer surface recess 123 on both sides in the X direction.

[0347] A land recess 137 may be formed in each land portion 133. A plurality of land recesses 137 may be formed in one land portion 133. The land recesses 137 may be aligned along the second sheet outer surface recess 123 and the bending line 108, or may be aligned in the Y direction. The land recesses 137 may be positioned parallel to each other. The land recesses 137 may be formed in the frame portion 132.

[0348] The land recesses 137 are formed by etching from the second main body surface 130b of the wick sheet 130 in the wick sheet etching step described above. As a result, the land recesses 137 may have curved wall surfaces, as shown in Figure 69. These wall surfaces define the land recesses 137 and may be curved in a shape that bulges toward the first main body surface 130a.

[0349] As shown in FIG. 69, the width w19 of the land recess 137 may be, for example, 50 μm to 150 μm. The width w19 refers to the dimension of the land recess 137 on the second main body surface 130b. The width w19 corresponds to the dimension of the land recess 137 in the Y direction. The depth h13 of the land recess 137 may be, for example, 20 μm to 120 μm. The depth h13 corresponds to the dimension of the land recess 137 in the Z direction.

[0350] As described above, according to this embodiment, land recess 137, which does not communicate with vapor passages 151 and 152, is located on second main body surface 130b of land portion 133, and land recess 137 overlaps second seat outer surface recess 123. This reduces the rigidity of land portion 133 in bending region 107. Therefore, when vapor chamber 101 is bent, land portion 133 can be easily bent.

[0351] Furthermore, according to this embodiment, the land recess 137 extends further out on both sides in the X direction than the second sheet outer surface recess 123. This reduces the rigidity of the land 133 even in the vicinity of the second sheet outer surface recess 123. Therefore, when the vapor chamber 101 is bent, the land 133 can be bent more easily.

[0352] In the above-described embodiment, an example has been described in which the second sheet outer surface recess 123 and the bending line 108 extend in the Y direction in a plan view. However, this is not limited to this. For example, the second sheet outer surface recess 123 may extend in a direction inclined toward the X direction in a plan view. As shown in Figures 67 and 68, the second sheet outer surface recess 123 and the bending line 108 may extend in a direction inclined toward the X direction in a plan view. Even in this case, the land recess 137 formed in each land portion 133 may overlap the second sheet outer surface recess 123 and be aligned along the second sheet outer surface recess 123 and the bending line 108.

[0353] The present invention is not limited to the above-described embodiments and modifications, and the components can be modified and embodied in practice without departing from the spirit of the invention. Furthermore, various inventions can be created by appropriately combining the multiple components disclosed in the above-described embodiments and modifications. Some components may be omitted from all the components shown in the above-described embodiments and modifications.

Claims

1. A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a vapor flow path portion through which the vapor of the working fluid passes, and a liquid flow path portion that communicates with the vapor flow path portion and through which the liquid of the working fluid passes, the steam flow path portion includes a steam passage extending along a first direction, The steam passages are provided in a plurality of directions intersecting the first direction, the first sheet includes a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove extending along a direction intersecting the first direction, the first seat groove is provided so as to overlap only one of the steam passages in a plan view and not to overlap two or more of the steam passages; the first seat groove is provided to a position overlapping with the liquid flow path portion in a plan view, the first seat groove has a first end portion provided at a position overlapping with the steam passage in a plan view, and a second end portion provided at a position overlapping with the liquid flow path portion in a plan view, The first seat groove is formed so that the cross-sectional area of ​​the flow path decreases from the second end toward the first end.

2. A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a vapor flow path portion through which the vapor of the working fluid passes, and a liquid flow path portion that communicates with the vapor flow path portion and through which the liquid of the working fluid passes, the steam flow path portion includes a steam passage extending along a first direction, The steam passages are provided in a plurality of directions intersecting the first direction, the first sheet includes a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove extending along a direction intersecting the first direction, the first seat groove is provided so as to overlap only one of the steam passages in a plan view and not to overlap two or more of the steam passages; the first seat groove is provided to a position overlapping with the liquid flow path portion in a plan view, the first seat groove has a first end portion provided at a position overlapping with the steam passage in a plan view, and a second end portion provided at a position overlapping with the liquid flow path portion in a plan view, The first seat groove is formed so that the cross-sectional area of ​​the flow path decreases from the first end toward the second end.

3. A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a vapor flow path portion through which the vapor of the working fluid passes, and a liquid flow path portion that communicates with the vapor flow path portion and through which the liquid of the working fluid passes, the steam flow path portion includes a plurality of steam passages extending along a first direction, the first sheet includes a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove being provided at a position overlapping with the steam passage in a plan view and extending along a direction intersecting the first direction, a plurality of the first seat grooves are provided along a direction intersecting the first direction, the first seat groove is provided to a position overlapping with the liquid flow path portion in a plan view, the first seat groove has a first end portion provided at a position overlapping with the steam passage in a plan view, and a second end portion provided at a position overlapping with the liquid flow path portion in a plan view, The first seat groove is formed so that the cross-sectional area of ​​the flow path decreases from the second end toward the first end.

4. A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a vapor flow path portion through which the vapor of the working fluid passes, and a liquid flow path portion that communicates with the vapor flow path portion and through which the liquid of the working fluid passes, the steam flow path portion includes a plurality of steam passages extending along a first direction, the first sheet includes a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove being provided at a position overlapping with the steam passage in a plan view and extending along a direction intersecting the first direction, a plurality of the first seat grooves are provided along a direction intersecting the first direction, the first seat groove is provided to a position overlapping with the liquid flow path portion in a plan view, the first seat groove has a first end portion provided at a position overlapping with the steam passage in a plan view, and a second end portion provided at a position overlapping with the liquid flow path portion in a plan view, The first seat groove is formed so that the cross-sectional area of ​​the flow path decreases from the first end toward the second end.

5. A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a plurality of land portions extending along a first direction, a vapor flow path portion through which vapor of the working fluid passes, the vapor flow path portion including vapor passages defined by adjacent land portions, and a liquid flow path portion communicating with the vapor flow path portion and through which liquid of the working fluid passes, the first sheet includes a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove being provided at a position overlapping with the steam passage in a plan view and extending along a direction intersecting the first direction, the first seat groove is provided between the land portions adjacent to each other in a plan view, the first seat groove is provided to a position overlapping with the land portion in a plan view, the first seat groove has a first end portion provided at a position overlapping with the steam passage in a plan view, and a second end portion provided at a position overlapping with the land portion in a plan view, The first seat groove is formed so that the cross-sectional area of ​​the flow path decreases from the second end toward the first end.

6. A vapor chamber in which a working fluid is sealed, A main sheet and a first sheet laminated on the main body sheet, the main body sheet includes a plurality of land portions extending along a first direction, a vapor flow path portion through which vapor of the working fluid passes, the vapor flow path portion including vapor passages defined by adjacent land portions, and a liquid flow path portion communicating with the vapor flow path portion and through which liquid of the working fluid passes, the first sheet includes a first sheet inner surface facing the main body sheet, and a first sheet groove provided on the first sheet inner surface, the first sheet groove being provided at a position overlapping with the steam passage in a plan view and extending along a direction intersecting the first direction, the first seat groove is provided between the land portions adjacent to each other in a plan view, the first seat groove is provided to a position overlapping with the land portion in a plan view, the first seat groove has a first end portion provided at a position overlapping with the steam passage in a plan view, and a second end portion provided at a position overlapping with the land portion in a plan view, The first seat groove is formed so that the cross-sectional area of ​​the flow path decreases from the first end toward the second end.

7. The vapor chamber according to claim 5 or 6, wherein the first seat groove is provided so as to extend to a position overlapping with the liquid flow path portion in a plan view.

8. the main body sheet includes a first main body surface facing the first sheet inner surface and a second main body surface located on the opposite side to the first main body surface, The vapor chamber according to any one of claims 1 to 6, wherein the liquid flow path portion is provided on the first main body surface.

9. The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove has an elongated rectangular shape or an elliptical shape in a plan view.

10. The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove has an elongated shape with rounded ends in a plan view.

11. The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove has a rosary-like shape in plan view, in which a plurality of circles are connected together and partially overlap in a direction intersecting the first direction.

12. The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove has a semicircular, triangular, rectangular or trapezoidal shape in cross section.

13. The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove has a partially circular shape in cross section on the inside of the first seat that is wider than the opening of the first seat groove.

14. The vapor chamber according to any one of claims 1 to 6, wherein the first sheet includes a plurality of the first sheet grooves.

15. The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove is disposed so as to be inclined with respect to the first direction in a plan view.

16. a second sheet laminated on the second main body surface of the main body sheet; the liquid flow path portion is also provided on the second main body surface, The vapor chamber of claim 8, wherein the second sheet includes a second sheet inner surface facing the second main body surface, and a second sheet groove provided on the second sheet inner surface, the second sheet groove being provided at a position overlapping with the vapor passage in a planar view and extending along a direction intersecting the first direction.

17. The vapor chamber has a bending region bent along a bending line, The vapor chamber according to any one of claims 1 to 6, wherein the first seat groove is arranged in the bending region.

18. a second sheet laminated on the second main body surface of the main body sheet; The vapor chamber according to claim 8 , wherein the second sheet includes a second sheet outer surface located on the opposite side to the main body sheet, and a second sheet outer surface recess located on the second sheet outer surface.

19. The vapor chamber according to claim 18 , wherein the first seat groove is provided at a position overlapping the second seat outer surface recess in a plan view.

20. The vapor chamber according to claim 19 , wherein the first seat groove is also provided at a position that does not overlap with the second seat outer surface recess in a plan view.

21. An electronic device comprising the vapor chamber according to any one of claims 1 to 6.

Images