Vapor chamber and electronic device

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] Devices that generate heat, such as central processing units (CPUs), light-emitting diodes (LEDs), and power semiconductors used in mobile devices such as mobile terminals and tablet terminals, are cooled by heat dissipation members such as heat pipes (see, for example, Patent Documents 1 and 2). In recent years, there has been a demand for thinner heat dissipation members in order to make mobile terminals thinner, and vapor chambers that can be made thinner than heat pipes have been developed. A working fluid is sealed inside the vapor chamber, and the working fluid absorbs the heat of the device and disperses it inside the vapor chamber, thereby cooling the device.

[0003] More specifically, the working fluid in the vapor chamber receives heat from the device in a portion (evaporation section) close to the device and evaporates to become vapor (working vapor). The working vapor diffuses in the vapor passage section in a direction away from the evaporation section, is cooled, and condenses to become liquid (working liquid). A liquid passage section having a capillary structure (wick) is provided in the vapor chamber, and the working liquid enters the liquid passage section from the vapor passage section, flows through the liquid passage section, and is transported toward the evaporation section. The working liquid then receives heat again in the evaporation section and evaporates. In this way, the working fluid circulates through the vapor chamber while repeatedly changing phases, that is, evaporating and condensing, thereby transferring heat from the device and increasing heat dissipation efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-204841 A [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; 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 communicating 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, A flow path cross-sectional area of ​​the first seat groove may be smaller than a flow path cross-sectional area of ​​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, A flow passage cross-sectional area of ​​the first seat groove may be larger than a flow passage cross-sectional area of ​​the main liquid flow passage groove.

[0009] A fourth aspect of the present disclosure is a vapor chamber according to any one 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 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.

[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 the first sheet groove arranged to cross the steam passage in a direction intersecting the first direction, and the first sheet groove including a first end provided at a position overlapping with the steam passage in a planar view and a second end provided at a position overlapping with the liquid flow path portion in a planar view.

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

[0014] A ninth aspect of the present disclosure is a vapor chamber according to each of the sixth aspect and the seventh aspect, The first seat groove may be formed so that a flow passage cross-sectional area becomes smaller 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 any one of the sixth to tenth aspects described above, The first sheet may include a plurality of the first sheet grooves, The first sheet grooves may be arranged radially in a plan view.

[0017] A twelfth aspect of the present disclosure is a vapor chamber according to any one 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 to 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 planar view and extending along a direction intersecting the first direction.

[0020] A fifteenth aspect of the present disclosure is a vapor chamber according to any one of the first to fourteenth aspects described above, The first sheet may include 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, the land portions being aligned along a second direction perpendicular to the first direction, and connecting portions 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, the land portions being aligned along a second direction perpendicular to the first direction, and connecting portions 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 method for producing a semiconductor device comprising the steps of: 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 bent 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 relative to 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 bend 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 a portion 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 described above, 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 described above, 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 described above, 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 beyond the second sheet outer surface recess on both sides in the first direction.

[0034] A twenty-ninth aspect of the present disclosure is a method for producing a semiconductor device comprising the steps of: 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 multiple second sheet outer surface recesses may be arranged in a direction intersecting the first direction, and at least some of the multiple second sheet outer surface recesses may overlap the space portion.

[0037] A thirty-second aspect of the present disclosure is a method for producing a semiconductor device comprising the steps of: 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. Effect of the Invention

[0038] According to the present disclosure, it is possible to improve heat dissipation efficiency. [Brief description of the drawings]

[0039] [Figure 1] FIG. 1 is a schematic perspective view illustrating an electronic device according to a first embodiment. [Diagram 2] FIG. 2 is a top view showing the vapor chamber according to the first embodiment. [Diagram 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. [Diagram 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 a partially enlarged cross-sectional view 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 overlaps with the upper sheet of FIG. [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. [Diagram 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 shows a modification of FIG. [Figure 29] FIG. 29 shows another modified example of FIG. [Diagram 30] FIG. 30 is a partially enlarged top view showing the vapor chamber according to the eighth embodiment. [Diagram 31] FIG. 31 shows a modification of FIG. [Diagram 32] FIG. 32 is a partially enlarged top view showing the vapor chamber according to the ninth embodiment. [Diagram 33] FIG. 33 shows a modification of FIG. [Diagram 34] FIG. 34 shows another modified example of FIG. [Diagram 35] FIG. 35 is a partially enlarged cross-sectional view showing the vapor chamber according to the tenth embodiment. [Diagram 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 the 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. [Diagram 40] FIG. 40 is a side view showing the vapor chamber bent along the bend line of FIG. [Diagram 41] FIG. 41 shows a modification of FIG. [Diagram 42] FIG. 42 is a schematic diagram showing an example of a vapor chamber according to the fifteenth embodiment. [Diagram 43] FIG. 43 is a schematic diagram showing another example of the vapor chamber according to the fifteenth embodiment. [Diagram 44] FIG. 44 is an external perspective view showing a vapor chamber according to the fifteenth embodiment. [Diagram 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] FIG. 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. [Diagram 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 a partially enlarged 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 shows a modification 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 bending 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 the 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 PREFERRED EMBODIMENTS

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

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

[0043] (First embodiment) A vapor chamber and an electronic device according to a first embodiment of the present disclosure will be described with reference to Figs. 1 to 12. The vapor chamber 1 according to this embodiment is a device mounted on an electronic device E in order to cool a device D (a device to be cooled) as a heat generating body housed in the electronic device E. Examples of the electronic device E include mobile terminals such as portable terminals and tablet terminals. Examples of the device D include electronic devices that generate heat, such as a central processing unit (CPU), a light emitting diode (LED), and a power semiconductor, used in a mobile terminal or the like.

[0044] Here, first, an electronic device E equipped with the vapor chamber 1 according to the present embodiment will be described by taking 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 used. The heat received by the vapor chamber 1 is released to the outside of the vapor chamber 1 via the working fluids 2a and 2b 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 the present embodiment will be described. As shown in Fig. 2 and Fig. 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 FIG. 2 and FIG. 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 laminated in this order. Note that, in this embodiment, an example in which the wick sheet 30 is composed of one sheet is shown, but the wick sheet 30 may be composed of two or more sheets, and the number of sheets of the wick sheet 30 is arbitrary.

[0047] The vapor chamber 1 is generally formed in a thin flat plate shape. The planar shape of the vapor chamber 1 is arbitrary, but 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 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 transverse direction will be described. 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 circular shape, an elliptical shape, 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 a region that overlaps with the device D in a planar view, and is a region where the device D is attached. The evaporation region SR can be disposed 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, which causes the working liquid 2b to evaporate and generate 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 periphery of that region. Therefore, the evaporation region SR includes the region that overlaps with the device D in a planar view and the periphery of that region.

[0050] Here, the plan view refers to a state in which 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. 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 in which the vapor chamber 1 is viewed from above or below corresponds to a 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, generating 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 attitude of the mobile terminal. However, in this embodiment, for convenience, the sheet that receives heat from the device D is referred to as the above-mentioned upper sheet 20, and the sheet that dissipates the received heat is referred to as the above-mentioned lower sheet 10. For this reason, the following description will be given with the lower sheet 10 disposed on the lower side and the upper sheet 20 disposed on the upper side.

[0053] 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 constituting a 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 generally flat, or may have a constant thickness generally.

[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 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 to the upper sheet inner surface 20a. The above-mentioned device D is attached to this upper sheet outer surface 20b. In addition, as shown in Figs. 3 and 5, the upper sheet 20 includes an upper sheet groove 70 (first sheet groove) provided on 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 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 to 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 in the frame body portion 32. The frame body portion 32 and the land portions 33 are portions that are not etched in the etching process described below, and the material of the wick sheet 30 remains.

[0061] In the illustrated example, the frame portion 32 is formed into 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, 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 along the X direction (left-right direction in FIG. 6) in a plan view, and the planar shape of each land portion 33 is an elongated rectangle. Moreover, each land portion 33 is lined up along the Y direction (up-down direction in FIG. 6) perpendicular to the X direction. Each land portion 33 may be lined up at regular intervals in the Y direction. Each land portion 33 may have a width w1 (see FIG. 7) of, 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 means the dimension in the Z direction at a position where a through portion 34 described later exists.

[0063] Here, the X direction is specified as the direction in which a second steam passage 52 of the steam flow path section 50 described later extends. 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. A wall surface 53a of the lower vapor flow path recess 53 and a wall surface 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 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 Fig. 3 and Fig. 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 the adjacent land sections 33. The second steam passage 52 extends along the X direction. The second steam passage 52 has a planar shape of an elongated rectangle. The plurality of land portions 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 steam passage 51 and the second steam passage 52 may extend from the wick sheet lower surface 30a to the wick sheet upper surface 30b, penetrating the wick sheet 30. The first steam passage 51 and the second steam passage 52 include a lower steam flow path recess 53 provided in the wick sheet lower surface 30a and an upper steam flow path recess 54 provided in the wick sheet upper surface 30b. The lower steam flow path recess 53 and the upper steam flow path recess 54 are in communication with each other, and the first steam passage 51 and the second steam 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 passage 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 later. Here, being formed in a concave shape on the wick sheet lower surface 30a means that it is formed so as to be recessed from the wick sheet lower surface 30a. As a result, the lower steam flow passage recess 53 has a wall surface 53a formed in a curved shape as shown in FIG. 7. This wall surface 53a defines the lower steam flow passage recess 53, and in the cross section shown in FIG. 7, it is curved so as to approach the opposing wall surface 53a as it proceeds toward the wick sheet upper surface 30b. As shown in FIG. 3 and FIG. 7, the working fluid 2b can adhere to this wall surface 53a. Such a lower steam flow passage recess 53 constitutes a part (lower half) of the first steam passage 51 and a part (lower half) of the second steam passage 52.

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

[0073] As shown in FIG. 7, the wall surface 53a of the lower steam passage recess 53 and the wall surface 54a of the upper steam passage 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 shape similar to the first steam passage 51, and the planar shape of the through-portion 34 in the second steam passage 52 is an elongated rectangular shape similar to the second steam passage 52. The through-portion 34 may be defined by a ridge line formed by joining the wall surface 53a of the lower steam passage recess 53 and the wall surface 54a of the upper steam passage recess 54 and projecting 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 the 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 wick sheet lower surface 30a and the wick sheet upper surface 30b. However, this is not limited thereto, and the through-hole 34 may be a position closer to the lower sheet 10 than the intermediate position, or may be a position 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-portion 34 defined by a ridge line formed to protrude inward, but are not limited to this. For example, the cross-sectional shapes of the first steam passage 51 and the second steam passage 52 may be trapezoidal or rectangular, or may be barrel-shaped.

[0076] The steam flow path portion 50 including the first steam path 51 and the second steam path 52 configured in this manner constitutes a 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 the 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, FIG. 3 shows the first steam passage 51 and the second steam passage 52, etc. in an enlarged manner, and the number and arrangement of these steam passages 51, 52, etc. differ from those in FIG. 2, and FIG. 6 to FIG. 10, etc.

[0078] Incidentally, although not shown, a plurality of support parts for supporting the land part 33 on the frame part 32 may be provided in the steam flow passage part 50. Also, a plurality of connecting parts 38 (see FIG. 37 and FIG. 38) for connecting the adjacent land parts 33 may be provided. The support parts and connecting parts 38 may be formed so as not to impede the flow of the working steam 2a diffusing in the steam flow passage part 50. For example, the support parts and connecting parts 38 may be disposed at a position close to 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 passage recess may be formed at a position close to the other. This allows the thickness of the support parts and connecting parts 38 to be thinner than the thickness of the wick sheet 30, and prevents the first steam passage 51 and the second steam passage 52 from being divided in the X direction and the Y direction.

[0079] The liquid flow path section 60 is a flow path through which the working liquid 2b mainly passes. The working steam 2a may also pass through the liquid flow path section 60. As shown in FIG. 3, FIG. 6, and FIG. 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 portion 33. The liquid flow path section 60 constitutes a part of the above-mentioned sealed space 3 and communicates with the steam 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 portion 33. The liquid flow path section 60 may be provided on the wick sheet upper surface 30b in the frame body section 32.

[0080] 8, the liquid flow path section 60 may be composed of a plurality of grooves provided on the wick sheet upper surface 30b. 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 connection 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 mainly flows 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 in parallel to each other at regular intervals.

[0082] The liquid flow path mainstream groove 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 mainstream groove 61 may have a wall surface 62 formed in a curved shape, as shown in Fig. 7. This wall surface 62 defines the liquid flow path mainstream groove 61, and may be curved in a concave shape 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-holes 34 of the steam passages 51, 52 and smaller than the width w1 of the land portion 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 at 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] As shown in FIG. 8, each liquid flow path communication groove 65 extends along a direction intersecting the X direction. In the illustrated example, each liquid flow path communication groove 65 extends along the Y direction and is formed perpendicular to the liquid flow path mainstream groove 61. Some liquid flow path communication grooves 65 communicate with adjacent liquid flow path mainstream grooves 61. Other liquid flow path communication grooves 65 communicate with the first steam passage 51 or the second steam passage 52 and the liquid flow path mainstream groove 61. That is, 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 the edge. In this way, the first steam passage 51 and the liquid flow path mainstream groove 61 communicate with each other, and the second steam passage 52 and the liquid flow path mainstream groove 61 communicate with each other.

[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 areas of the steam 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 be aligned parallel to each other at regular intervals.

[0086] The liquid flow path communication groove 65 may be formed by etching, similar to the liquid flow path mainstream groove 61. As a result, the liquid flow path communication groove 65 may have a wall surface (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 communication groove 65 shown in FIG. 8 is smaller than the width w2 of the through portion 34 of the steam passages 51, 52 and smaller than the width w1 of the land portion 33. The width w4 of the liquid flow path communication groove 65 may be equal to the width w3 of the liquid flow path mainstream groove 61. However, this is not limited to the above, and the width w4 of the liquid flow path communication 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 communication groove 65 may be equal to the depth h1 of the liquid flow path mainstream groove 61. However, this is not limited to the above, and the depth of the liquid flow path communication groove 65 may be deeper or shallower 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 mainstream grooves 61. Each liquid flow path convex row 63 includes a plurality of liquid flow path convex portions 64 aligned in the X direction. The liquid flow path convex portions 64 abut against the upper sheet inner surface 20a. Each liquid flow path convex portion 64 is formed in a rectangular shape such that the X direction is the longitudinal direction in a plan view. A liquid flow path mainstream groove 61 is interposed between adjacent liquid flow path convex portions 64 in the Y direction. A liquid flow path connection groove 65 is interposed between adjacent liquid flow path convex portions 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 manner. More specifically, the liquid flow path convex portions 64 of the liquid flow path convex portion rows 63 adjacent to each other in the Y direction may be arranged to be shifted from each other in the X direction. This shift 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 means 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 mainstream 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 arrangement, 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 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 at 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, and the heat dissipation efficiency of the vapor chamber 1 can be improved. In addition, when pure water is used as the working fluids 2a and 2b, corrosion can be prevented. Note that, as long as the desired heat dissipation efficiency can be obtained and corrosion can be prevented, other metal materials such as aluminum and titanium, or other metal alloy materials such as stainless steel may be used for these sheets 10, 20, and 30.

[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, and the vapor chamber 1 can function properly. On the other hand, by making the thickness t1 1000 μm or less, the vapor chamber 1 can be prevented from becoming 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, the vapor chamber 1 can be prevented from becoming thick. 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 appropriately secured, and the vapor chamber 1 can function appropriately. On the other hand, by making it 400 μm or less, the vapor chamber 1 can be prevented from becoming thick.

[0095] As described above, the upper sheet 20 of the vapor chamber 1 according to the present embodiment includes the upper sheet groove 70 provided on 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 a state in which the wick sheet 30 and the upper sheet 20 are overlapped. As shown in FIG. 10, the upper sheet groove 70 is provided at a position overlapping 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 the second steam passage 52 in a plan view, and the entire upper sheet groove 70 overlaps the second steam passage 52 in a plan view. It can also be said that the upper sheet groove 70 is provided between the land portions 33 adjacent to each other in a plan view. The upper sheet groove 70 may be provided at a position overlapping the first steam passage 51 in a plan view. In this case, the upper sheet groove 70 may be provided at a position overlapping 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 along a direction intersecting the X direction. In the illustrated example, the upper sheet groove 70 extends along the Y direction perpendicular to the X direction. The planar shape of the upper sheet groove 70 is an elongated rectangular shape. 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 (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 (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 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 wall surface 73 formed in a curved shape, as shown in Figure 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 Figure 11, the cross-sectional shape of the upper sheet groove 70 is semicircular.

[0100] The upper sheet groove 70 has a small flow passage cross-sectional area so that the working fluid 2b mainly flows by capillary action. The upper sheet groove 70 is a groove having a flow passage cross-sectional area smaller than the flow passage cross-sectional area of ​​the steam passages 51, 52. The upper sheet groove 70 promotes the movement of the working fluid 2b between the steam passages 51, 52 and the liquid passage portion 60. The flow passage cross-sectional area of ​​the upper sheet groove 70 may be equal to the flow passage cross-sectional area of ​​the liquid passage mainstream groove 61. However, this is not limited thereto, and the flow passage cross-sectional area of ​​the upper sheet groove 70 may be smaller than the flow passage cross-sectional area of ​​the liquid passage mainstream groove 61. In this case, the capillary action of the upper sheet groove 70 gives the working fluid 2b a driving force from the liquid passage portion 60 toward the upper sheet groove 70, and the working fluid 2b in the liquid passage portion 60 can be quickly moved to the steam passages 51, 52 through the upper sheet groove 70. 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, so that 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 greater than the width w3 (see Fig. 7) of the liquid flow path mainstream groove 61, and may be greater 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 areas of the steam passages 51, 52, the length L1 of the upper sheet groove 70 may be greater than the width w6 of the upper sheet groove 70 described later. The length L1 of the upper sheet groove 70 may be greater than 5 µm, for example.

[0102] The width w6 (dimension in the X direction) of the upper sheet groove 70 shown in Fig. 9 and Fig. 11 may be equal to the width w3 (see Fig. 7) of the liquid flow path mainstream groove 61. However, this is not limited thereto, 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 (dimension in the X direction) of the upper sheet groove 70 may be, for example, 5 µm to 150 µm. Here, the width w6 of the upper sheet groove 70 means 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 the upper sheet grooves 70 adjacent to each other in the X direction shown in FIG. 11 may be equal to the gap between the liquid flow mainstream grooves 61 adjacent to each other in the Y direction, i.e., the width w5 of the liquid flow convex portion 64 (see FIG. 8), or may be smaller than the width w5 of the liquid flow convex portion 64. In this case, more upper sheet grooves 70 can be arranged, and a sufficient amount of working fluid 2b can be circulated between the steam passages 51, 52 and the liquid flow path portion 60. However, this is not limited to the above, and the gap w7 between the upper sheet grooves 70 adjacent to each other in the X direction may be larger than the width w5 of the liquid flow convex portion 64. The gap w7 between the upper sheet grooves 70 adjacent to each other in the X direction may be, for example, 3 μm to 500 μm.

[0105] In this embodiment, the planar shape of the upper sheet groove 70 is an elongated rectangular shape, and the cross-sectional shape of the upper sheet groove 70 is semicircular, but this is not limited to this, and the shape of the upper sheet 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 sheet 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 a 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. Then, 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-processed 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 step, as in the lower sheet preparation step, 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. By this etching, the upper sheet groove 70 described above is formed in the upper sheet 20. Alternatively, the upper sheet base material may be pressed to form the upper sheet 20 having a desired planar shape. The upper sheet groove 70 may also 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 step may include a material sheet preparation step of preparing a metal material sheet, and an etching step of etching the metal material sheet. First, in the material sheet preparation step, a flat metal material sheet having a desired thickness is prepared. The metal material sheet may be a rolled material. Then, in the etching step, 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 as well as a vapor flow path portion 50 and a liquid flow path portion 60. In this manner, the 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. In addition, the steam flow path section 50 and the liquid flow path section 60 may be formed by etching simultaneously, 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 step, the lower sheet 10, the upper sheet 20, and the wick sheet 30 are joined in the joining step. First, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are laminated in this order. At this time, the sheets 10, 20, and 30 may be aligned using the alignment hole 12 of the lower sheet 10, the alignment hole 35 of the wick sheet 30, and the alignment hole 22 of the upper sheet 20. Next, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are temporarily fixed. For example, the sheets 10, 20, and 30 may be temporarily fixed by spot welding or laser welding. Next, the lower sheet 10, the wick sheet 30, and the upper sheet 20 are permanently joined by thermocompression bonding. For example, the sheets 10, 20, and 30 may be joined 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 as a sealing step. This blocks communication between the sealed space 3 and the outside, and seals 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 the present embodiment can be obtained.

[0117] Next, a method for operating the vapor chamber 1, that is, a method for 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 liquid 2b in the sealed space 3 adheres to the wall surfaces of the sealed space 3, i.e., 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, due to its surface tension. The working fluid 2b may also adhere to a portion of the lower sheet inner surface 10b of the lower sheet 10 that is exposed to the lower steam flow passage recess 53. Furthermore, the working fluid 2b may also adhere to a portion of the upper sheet inner surface 20a of the upper sheet 20 that is exposed to the upper steam flow passage recess 54, the liquid flow passage main groove 61, and the liquid flow passage connecting groove 65.

[0119] In this state, when the device D generates heat, the working fluid 2b present in the evaporation region SR (see FIG. 6) receives heat from the device D. The received heat is absorbed as latent heat, and the working fluid 2b evaporates (vaporizes), generating working steam 2a. The generated working steam 2a diffuses within the first steam passage 51 and the second steam passage 52 that constitute the sealed space 3. More specifically, the working steam 2a diffuses in the X direction mainly in the portion of the first steam passage 51 that extends in the X direction and in the second steam passage 52 (see the 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 dissipating 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 loses the latent heat absorbed in the evaporation region SR by dissipating heat to the lower sheet 10 in the condensation region CR. As a result, the working vapor 2a condenses to generate the working liquid 2b. The generated working liquid 2b adheres to the wall surfaces 53a, 54a of the vapor flow 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 region of the liquid flow path section 60 other than the evaporation region SR (i.e., the condensation region CR) is transported toward the evaporation region SR by the capillary action of each liquid flow path mainstream groove 61 (see the dashed arrow in FIG. 6). As a result, the working liquid 2b adhered 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 groove 65, and enters the liquid flow path mainstream groove 61. In this manner, 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 propulsive 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 flow between the adjacent liquid flow path mainstream grooves 61, and prevents the occurrence of dryout in the liquid flow path mainstream groove 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 smoothly transported 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 communication 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 a large flow path cross-sectional area. 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 changing phases, that is, evaporating and condensing. This causes the heat of the device D to be diffused and released. As a result, the device D is cooled.

[0124] Here, 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 with the steam passages 51, 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 move smoothly from the steam passages 51, 52 to the liquid passage portion 60 through the upper sheet groove 70, and can smoothly enter the liquid passage mainstream groove 61. Also, in the evaporation region SR, the working fluid 2b can move from the liquid passage portion 60 to the steam passages 51, 52 through the upper sheet groove 70. Therefore, the working fluid 2b that has moved to the steam passages 51, 52 can effectively absorb heat from the device D, and can effectively cool the device D.

[0125] Thus, according to this embodiment, the upper sheet 20 includes the upper sheet groove 70 provided on the upper sheet inner surface 20a, which is provided at a position overlapping with the vapor passages 51, 52 in a plan view and extends along a direction intersecting the X direction. This 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 return of the working fluids 2a, 2b in the vapor chamber 1. As a result, the heat dissipation efficiency of the vapor chamber 1 can be improved.

[0126] 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 provides the working fluid 2b with a driving force from the liquid flow path portion 60 toward the upper sheet groove 70 by the capillary action of the upper sheet groove 70, and the working fluid 2b in the liquid flow path portion 60 can be quickly moved to the vapor paths 51 and 52 through the upper sheet groove 70. Therefore, when such an upper sheet groove 70 is disposed in the evaporation region SR, the movement of the working fluid 2b in the evaporation region SR from the liquid flow path portion 60 to the vapor paths 51 and 52 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] 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 provides the working fluid 2b with a driving force from the upper sheet groove 70 toward the liquid flow path section 60 by the capillary action of the upper sheet groove 70, and the working fluid 2b in the vapor paths 51 and 52 can be moved quickly to the liquid flow path section 60 through the upper sheet groove 70. 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 paths 51 and 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 and 2b in the vapor chamber 1 can be further promoted.

[0128] Moreover, 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 groove 70 is provided on the upper sheet inner surface 20a facing the wick sheet upper surface 30b. This allows the working fluid 2b that has flowed through the upper sheet groove 70 to move smoothly to the vapor passages 51, 52 or the liquid flow path portion 60. This further promotes the return of the working fluids 2a, 2b in the vapor chamber 1.

[0129] In the above-described embodiment, the liquid flow path section 60 is provided on the upper surface 30b of the wick sheet. However, the present invention is not limited to this, and the liquid flow path section 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, 52. The working fluid 2b can also flow from the vapor paths 51, 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, to the liquid flow path portion 60. This can promote the return of the working fluids 2a, 2b in 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 communication groove 65 located closest to the steam paths 51 and 52 of 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 as the liquid flow path communication groove 65 located closest to the steam paths 51 and 52 of the liquid flow path section 60 in the X direction, such that the first end 71 or the second end 72 faces the liquid flow path communication groove 65 in the Y direction. 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 the upper sheet grooves 70, it is possible to effectively promote the movement of the working fluid 2b between the steam paths 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, the present invention 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) being rounded. For example, as shown in FIG. 15, the planar shape of the upper sheet groove 70 may be an elongated ellipse 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 partially overlapped and connected 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 a semicircular shape (see FIG. 11). However, the present invention is not limited to this. For example, as shown in FIG. 17, the cross-sectional shape of the upper sheet groove 70 may be a triangular shape. For example, as shown in FIG. 18, the cross-sectional shape of the upper sheet groove 70 may be a rectangular shape. For example, as shown in FIG. 19, the cross-sectional shape of the upper sheet groove 70 may be a trapezoidal shape. For example, as shown in FIG. 20, the cross-sectional shape of the upper sheet groove 70 may be a partial circle having a width on the inside that is wider 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 passage cross-sectional area smaller than the flow passage cross-sectional area 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 first sheet groove is provided in a position overlapping with the liquid flow path portion in a plan view, and is provided so as to cross the steam path in a direction intersecting the first direction, and the 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 at a position overlapping 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 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 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 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] Thus, according to this embodiment, the upper sheet groove 70 is provided over 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 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 steam 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, and the movement of the working steam 2a from the liquid flow path portion 60 to the vapor passages 51, 52 in the evaporation region SR can be effectively promoted. 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 liquid flow mainstream groove 61, the movement of the working steam 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 to equalize the amount of working fluid 2b moving to each liquid flow path portion 60 provided in the land portions 33 adjacent to each other. 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 in the vapor chamber 1 can be further promoted.

[0140] In the above-described embodiment, an example has been described in which the first end 71 and the second end 72 of the upper sheet 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 with 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 such a case, the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid passage section 60 can be effectively promoted. 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 passage section 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 passage section 60 can be quickly moved to the vapor passages 51, 52 through the upper sheet groove 70, and the movement of the working vapor 2a from the liquid passage section 60 to the vapor passages 51, 52 in the evaporation region SR can be effectively promoted. 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 liquid passage mainstream groove 61, the movement of the working vapor 2a from the liquid passage section 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. In addition, the amount of working fluid 2b moving to each liquid flow path section 60 can be made uniform, and it is possible to prevent a large amount of working fluid 2b from being unevenly distributed 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 in 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 in that the first sheet groove includes 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 passage portion in a plan view, and the 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] In this embodiment, as shown in Fig. 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 on the side overlapping the steam passages 51, 52 in a plan view, among both end sections in a direction intersecting the X direction, and the second end 72 is defined as the end on the side overlapping the liquid flow path section 60 in a plan view, among both end sections in a direction intersecting the X direction. In the example shown in Fig. 23, the first end 71 overlaps the second steam passage 52 in a plan view, and the second end 72 overlaps the liquid flow path mainstream groove 61 in a plan view.

[0145] 23, the upper sheet grooves 70 may be provided at positions overlapping with the edge of the land portion 33 on the positive side in the Y direction in a plan view and at positions overlapping with the edge of the land portion 33 on the negative side in the Y direction in a plan view. At the positions overlapping with the edge of the land portion 33 on the positive side in the Y direction in a plan view, the upper sheet grooves 70 may be aligned along the X direction. Also, at the positions overlapping with the edge of the land portion 33 on the negative side in the Y direction in a plan view, the upper sheet grooves 70 may 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 steam 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 steam 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 steam passages 51 and 52 in the evaporation region SR can be effectively promoted. In addition, during a sudden temperature rise, the working steam 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved to the steam passages 51 and 52 through the upper sheet groove 70, and the movement of the working steam 2a from the liquid flow path portion 60 to the steam passages 51 and 52 in the evaporation region SR can be effectively promoted. Furthermore, when the flow passage cross-sectional area of ​​the upper sheet groove 70 is larger than that of the liquid flow passage main groove 61, the movement of the working vapor 2a from the liquid flow passage portion 60 to the vapor passages 51, 52 in the evaporation region SR can be more effectively promoted. As a result, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be more effectively 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 a plurality of first sheet grooves are provided so as to cross the steam passage in a direction intersecting the first direction, and each first sheet groove includes 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, and 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 planar view and a second end 72′ arranged at a position overlapping with the liquid flow path portion 60 in a planar 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 main groove 61 in a planar view.

[0152] 24, the upper sheet groove 70' may be provided at a position overlapping with the edge on the positive side in the Y direction of one land portion 33 (for example, the land portion 33 arranged in the center in FIG. 24) in a plan view, and at a position overlapping with the edge on the negative side in 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 the positions overlapping with the edge on the positive side in 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 overlapping 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 Fig. 24, the upper sheet grooves 70' do not have to be provided at positions overlapping with the positive edge in the Y direction of other land portions 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 Fig. 24) and at positions overlapping with the negative edge in the Y direction of the other land portions 33 in plan view. At positions overlapping with the positive edge in the Y direction of the other land portions 33 in plan view, the upper sheet grooves 70 may be aligned along the X direction. Moreover, even at positions overlapping with the negative edge in the Y direction of the other land portions 33 in plan view, the upper sheet grooves 70 may be aligned alternately in the X direction.

[0154] As described above, according to the present embodiment, the 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 the steam passages 51, 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 can effectively promote 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 can effectively promote 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. In addition, 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, 52, effectively promoting the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor paths 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 liquid flow mainstream groove 61, the movement of the working vapor 2a from the liquid flow path portion 60 to the vapor paths 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 promoted.

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

[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 sheet 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 becomes smaller from the second end 72 to the first end 71. That is, the upper sheet groove 70 is formed so as to taper 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 becomes smaller from the second end 72 to the first end 71. Also, the upper sheet groove 70 may be formed so that the depth h2 of the upper sheet groove 70 becomes shallower 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 becomes smaller from the second end 72 to the first end 71. As a result, the capillary action of the upper sheet groove 70 imparts a driving force to the working fluid 2b from the liquid flow path portion 60 toward the upper sheet groove 70, and 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. 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. In addition, when the temperature rises suddenly, the working steam 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, and the movement of the working steam 2a from the liquid flow path portion 60 to the vapor paths 51 and 52 in the evaporation region SR can be effectively promoted. Furthermore, when the flow passage cross-sectional area of ​​the upper sheet groove 70 is larger than that of the liquid flow passage main groove 61, the movement of the working vapor 2a from the liquid flow passage portion 60 to the vapor passages 51, 52 in the evaporation region SR can be more effectively promoted. As a result, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be more effectively 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 sheet 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 becomes smaller from the first end 71 to the second end 72. That is, the upper sheet groove 70 is formed so as to taper 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 becomes smaller from the first end 71 to the second end 72. Also, the upper sheet groove 70 may be formed so that the depth h2 of the upper sheet groove 70 becomes shallower 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 becomes smaller from the first end 71 toward the second end 72. As a result, the capillary action of the upper sheet groove 70 imparts a driving force from the upper sheet groove 70 toward the liquid flow path portion 60 to the working fluid 2b, and the working fluid 2b in the vapor paths 51 and 52 can be quickly moved to the liquid flow path portion 60 through the upper sheet groove 70. 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 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 steam 2a evaporated from the working fluid 2b in the liquid flow path portion 60 can be quickly moved to the vapor paths 51 and 52 through the upper sheet groove 70, and the movement of the working steam 2a from the liquid flow path portion 60 to the vapor paths 51 and 52 in the evaporation region SR can be effectively promoted. Furthermore, when the flow passage cross-sectional area of ​​the upper sheet groove 70 is larger than that of the liquid flow passage main groove 61, the movement of the working vapor 2a from the liquid flow passage portion 60 to the vapor passages 51, 52 in the evaporation region SR can be more effectively promoted. As a result, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be more effectively 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 from the third embodiment shown in Figure 23 in that the first sheet groove is arranged so as to be inclined with respect to the first direction in a 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 Fig. 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] In the example shown in Fig. 27, at a position overlapping with 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 on the positive side in the X direction and the positive side in the Y direction relative to the second end 72. Furthermore, at a position overlapping with 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 in the X direction so as to be parallel to each other. In the example shown in Fig. 27, four upper sheet grooves 70 are aligned.

[0168] On the other hand, at a position overlapping with 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 on the positive side in the X direction and on the negative side in the Y direction relative to the second end 72. Also, at a position overlapping with 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 in the X direction so as to be parallel to each other. In the example shown in Fig. 27, four upper sheet grooves 70 are aligned.

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

[0170] Thus, according to this embodiment, the upper sheet groove 70 is arranged so as to be inclined with respect to the X direction in a plan view. As a result, 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. In particular, even if the liquid flow path section 60 is arranged at a position close to 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 to the vapor passages 51 and 52 through the upper sheet groove 70, and the movement of the working vapor 2a in the evaporation region SR from the liquid flow path section 60 to the vapor passages 51 and 52 can be effectively promoted. 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, and the working vapor 2a can 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 in the X direction parallel to each other at positions overlapping with the edges of the land portions 33 in a plan view. However, this is not limited thereto, and the upper sheet grooves 70 do not have to be parallel to each other, for example, as shown in Figs. 28 and 29.

[0172] 28, six upper sheet grooves 70 are lined up along the X direction at positions overlapping with the edge of the land portion 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. Additionally, 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 sheet grooves 70 are also lined up along the X direction at positions overlapping with the edge of the land portion 33 on the negative 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 negative side in the Y direction than their second ends 72. Also, 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 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. In addition, 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 section 60 can be quickly moved to the vapor passages 51 and 52 through the upper sheet groove 70, and the movement of the working vapor 2a in the evaporation region SR from the liquid flow path section 60 to the vapor passages 51 and 52 can be effectively promoted. In particular, when a plurality of condensation regions CR are disposed, the flow of the working vapor 2a can be directed to each condensation region CR, and the working vapor 2a can be quickly transported to each condensation region CR. This allows the transport efficiency of the working fluid 2b to be improved, and the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be promoted.

[0175] 29, six upper sheet grooves 70 are lined up along the X direction at positions that overlap with the edge of the land portion 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 positive side in the X direction and on the positive side in the Y direction than their second ends 72. Also, 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 negative side in the X direction and on the positive side in the Y direction than their second ends 72.

[0176] Meanwhile, six upper sheet grooves 70 are also lined up along the X direction at positions overlapping with the edge of the land portion 33 on the negative 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 positive side in the X direction and on the negative side in the Y direction than their second ends 72. Furthermore, 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 negative side in the X direction and on 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 a plurality of first sheet grooves are radially arranged in a 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 denoted 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 to be inclined with respect to the X direction. Also, each upper sheet groove 70 is arranged so that a second end 72 faces a specific position of the liquid flow path section 60. Each upper sheet groove 70 is arranged radially such that a gap w7 (see Fig. 11) between adjacent upper sheet grooves 70 in the X direction becomes smaller from the steam passages 51, 52 side toward the liquid flow path section 60 side.

[0181] Thus, according to this embodiment, the upper sheet grooves 70 are radially arranged in a plan view. As a result, for example, the working fluid 2b in the vapor passages 51 and 52 can be moved so as to concentrate on the liquid flow path section 60 in the condensation region CR. Therefore, a sufficient amount of working fluid 2b can be moved to the liquid flow path section 60. In addition, 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 to the vapor passages 51 and 52 through the upper sheet grooves 70, and 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 can be effectively promoted. In particular, when a plurality of condensation regions CR are arranged, the flow of the working vapor 2a can be directed to each condensation region CR, and the working vapor 2a can 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 in the vapor chamber 1 can be promoted.

[0182] In the above-described embodiment, an example has been described in which the upper sheet grooves 70 are radially arranged such that the gap w7 between adjacent upper sheet grooves 70 in the X direction becomes smaller from the steam passages 51, 52 side to the liquid flow path section 60 side. However, this is not limited to the above, 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 becomes smaller from the liquid flow path section 60 side to the steam passages 51, 52 side. Each upper sheet groove 70 may be arranged such that the first end 71 faces a specific position of 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 from the second embodiment shown in Figures 21 and 22 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 in the second embodiment shown in Figures 21 and 22 are denoted 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 the upper sheet grooves 70 adjacent to each other. The upper sheet 20 may include a plurality of 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 disposed 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 the upper sheet grooves 70 adjacent to each other.

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

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

[0190] Thus, 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 makes it possible to suppress 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 return flow of the working fluids 2a, 2b in 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 limited to this, and the upper sheet grooves 70 and the upper sheet communication grooves 75 may be arranged in any manner.

[0192] 33, the upper sheet grooves 70 are arranged in a staggered manner, i.e., the upper sheet grooves 70 adjacent to each other in the X direction are shifted from each other in the Y direction. This shift amount 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, and communicates with each upper sheet groove 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 working fluid 2b can be moved between the upper sheet grooves 70 due to the capillary action of the upper sheet communication grooves 75. Therefore, uneven distribution of the working fluid 2b between the upper sheet grooves 70 can be suppressed. As a result, the transport efficiency of the working fluid 2b can be improved, and the return flow of the working fluids 2a, 2b in 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, the present invention is not limited to this, and the upper sheet communication grooves 75 may be arranged in a lattice pattern as shown in Fig. 34. That is, the upper sheet communication grooves 75 may be aligned in the X direction and the Y direction.

[0196] Even in such a case, the working fluid 2b can be moved between the upper sheet grooves 70 due to the capillary action of the upper sheet communication grooves 75. Therefore, uneven distribution of the working fluid 2b between the upper sheet grooves 70 can be suppressed. As a result, the transport efficiency of the working fluid 2b can be improved, and the return flow of the working fluids 2a, 2b in 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 Fig. 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 second sheet inner surface, which is provided at a position overlapping with the steam passage in a plan view, and extends along a direction intersecting the first direction, but the other configurations are substantially the same as those of the first embodiment shown in Figs. 1 to 20. Note that in Fig. 35, the same parts as those of the first embodiment shown in Figs. 1 to 20 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0199] In this embodiment, as shown in Fig. 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 is also provided on the lower surface 30a of the wick sheet.

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

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

[0202] Furthermore, according to this embodiment, the lower sheet 10 includes a lower sheet groove 80 provided on the lower sheet inner surface 10b, the lower sheet groove 80 being provided at a position overlapping with the vapor passages 51, 52 in a plan view and extending along a direction intersecting the X direction. This can further promote 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 can further promote the return of the working fluids 2a, 2b in 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 area recessed toward the steam passage, and the first sheet groove is disposed in the recessed area, and other configurations are substantially the same as those of the first embodiment shown in Figs. 1 to 20. In Fig. 36, the same parts as those of the first embodiment shown in Figs. 1 to 20 are denoted 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 steam passages 51, 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 steam passages 51, 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 have to be provided in a region other than the recessed region DR, i.e., in the flat region FR.

[0207] Thus, according to the present 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 steam passages 51, 52 is smaller than the flow path cross-sectional area of ​​the steam passages 51, 52 in other regions. As a result, in the recessed region DR, the working steam 2a is likely to condense and the working fluid 2b is likely to be generated. Therefore, there is a risk that the working fluid 2b will stagnate in the recessed region DR. In contrast, since the upper sheet groove 70 is disposed in the recessed region DR, the movement of the working fluid 2b between the steam passages 51, 52 and the liquid flow path portion 60 in the recessed region DR can be promoted. Therefore, the stagnation of the working fluid 2b in the recessed region DR can be suppressed. As a result, the reflux of the working fluids 2a, 2b in 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 sheet groove is provided at a position overlapping 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 denoted by the same reference numerals and detailed description thereof will be omitted.

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

[0211] 37, the connecting parts 38 are disposed in a position close to the wick sheet lower surface 30a of the wick sheet 30. More specifically, the connecting parts 38 are disposed in a 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 need to be provided in any position other than the position facing the connecting parts 38.

[0212] Thus, according to this embodiment, the upper sheet groove 70 is provided at a position overlapping the connecting portion 38 in a plan view. At the position where the connecting portion 38 is provided, the flow path cross-sectional area of ​​the steam passages 51, 52 is smaller than the flow path cross-sectional area of ​​the steam passages 51, 52 at other positions. As a result, at the position where the connecting portion 38 is provided, the working steam 2a is likely to condense and the working fluid 2b is likely to be generated. Therefore, there is a risk that the working fluid 2b will stagnate at that position. In contrast, since the upper sheet groove 70 is provided at a position overlapping the connecting portion 38 in a plan view, the flow of the working fluid 2b between the steam passages 51, 52 and the liquid flow path portion 60 at that position can be promoted, and the stagnation of the working fluid 2b can be suppressed. Therefore, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be effectively promoted.

[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 in that the first sheet groove is provided in a region adjacent to the connecting portion along the first direction in a plan view, and other configurations are substantially the same as those of the first embodiment shown in Fig. 1 to Fig. 20. In Fig. 38, the same parts as those of the first embodiment shown in Fig. 1 to Fig. 20 are denoted by the same reference numerals and detailed description thereof will be omitted.

[0215] 38, in the present 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 disposed at a position close to the wick sheet lower surface 30a of the wick sheet 30. The connecting portion 38 may be disposed in a 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 secured at a position close to the wick sheet upper surface 30b of the wick sheet 30. The upper sheet groove 70 may not be provided at a position other than the region adjacent to the connecting portion 38 along the X direction in a plan view, that is, at a position away from the connecting portion 38 in a plan view. Here, the region adjacent to the connecting portion 38 along the X direction in a 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 a plan view.

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

[0218] In addition, 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 the above, 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] Thus, according to this embodiment, the upper sheet groove 70 is provided in the region adjacent to the connecting portion 38 along the X direction in a plan view. At the position where the connecting portion 38 is provided, the flow path cross-sectional area of ​​the steam passages 51, 52 is smaller than the flow path cross-sectional area of ​​the steam passages 51, 52 at other positions. As a result, the working steam 2a is likely to condense and the working liquid 2b is likely to be generated even in the region adjacent to the connecting portion 38 along the X direction. Therefore, there is a risk that the working liquid 2b will stagnate in this region. On the other hand, since the upper sheet groove 70 is provided in the region adjacent to the connecting portion 38 along the X direction in a plan view, the movement of the working liquid 2b between the steam passages 51, 52 and the liquid flow path portion 60 in this region can be promoted, and the stagnation of the working liquid 2b can be suppressed. Therefore, the reflux of the working fluids 2a, 2b in the vapor chamber 1 can be effectively promoted.

[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 sheet groove is disposed in the bent region, and the other configurations are substantially the same as those of the first embodiment shown in Figures 1 to 20. Note that in Figures 39 and 40, the same parts as those in the first embodiment shown in Figures 1 to 20 are denoted 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 bent 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 located on the inside and the upper sheet 20 is located on the outside. The bending angle may be any angle. In the example shown in FIG. 40, the bending angle is 90 degrees (right angle). Therefore, the cross-sectional shape of the vapor chamber 1 is approximately L-shaped. However, this is not limited to this, and for example, the vapor chamber 1 may be bent so that the cross-sectional shape of the vapor chamber 1 is U-shaped. Also, 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 or the like. By bending the vapor chamber 1 in this way, the degree of freedom of arrangement of the vapor chamber 1 in the housing H can be improved. Here, the bending angle means the angle formed by 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 in the manufacturing process of the vapor chamber 1 by bending the flat vapor chamber 1 along the bending line BL in a bending step after the sealing step.

[0225] In this embodiment, the upper sheet groove 70 is disposed 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 disposed in regions other than the bending region BR, i.e., the first region RR1 and the second region RR2.

[0226] Thus, according to this embodiment, the upper sheet groove 70 is arranged in the bending region BR. When the vapor chamber 1 is bent, the lower sheet 10 located on the inside may be deformed to be concave toward the lower steam flow path recess 53 due to compressive stress in the bending region BR. Also, the upper sheet 20 located on the outside may be deformed to be concave toward the upper steam flow path recess 54 due to tensile stress in the bending region BR. 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, in the bending region BR, the flow path cross-sectional area of ​​the steam paths 51, 52 may be reduced. As a result, in the bending region BR, the working steam 2a may be easily condensed and the working fluid 2b may be easily generated. Therefore, there is a risk that the working fluid 2b may stagnate in the bending region BR. On the other hand, since the upper sheet groove 70 is arranged in the bending region BR, the movement of the working fluid 2b between the steam paths 51, 52 and the liquid flow path portion 60 in the bending region BR can be promoted. Therefore, it is possible to suppress the working fluid 2b from stagnation in the curved region BR, and as a result, the reflux of the working fluids 2a and 2b in the vapor chamber 1 can be effectively promoted.

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

[0228] In each of the above-mentioned embodiments, an example has been described in which the vapor chamber 1 is composed of the lower sheet 10, the upper sheet 20, and the wick sheet 30. However, the present invention is not limited to this, and the vapor chamber 1 may be composed of the upper sheet 20 and the 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. The 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 wick sheet upper surface 30b, but does not extend to the wick sheet lower surface 30a, and does not penetrate the wick sheet 30. That is, 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 an 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 at 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, since the upper sheet 20 includes the upper sheet grooves 70, it is possible to promote the movement of the working fluid 2b between the vapor passages 51, 52 and the liquid passage portion 60. This promotes the return of the working fluids 2a, 2b in 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 path resistance, which causes a problem of obstructing the flow of working vapor in the vapor flow path.

[0237] An object of the present embodiment is to provide a vapor chamber and an electronic device that can improve heat dissipation efficiency even when bent.

[0238] Vapor chamber 101 according to the present 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. Depending on the positional relationship between the electronic device E that generates heat and the housing member Ha that dissipates the heat, the vapor chamber 101 may be bent. The housing member Ha is a member that constitutes the housing H.

[0239] As an example, there is a case where the electronic device D and the 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 described later, or to a first region 105 or a second region 106 described later. As another example, there is a case where the electronic device D and the housing member Ha are arranged as shown in FIG. 43. In this case, the vapor chamber 101 is bent 180° 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. Although FIGS. 42 and 42 show an example of the vapor chamber 101 bent at one bending line 108 (see FIGS. 44 and 45), the present invention is not limited thereto. The vapor chamber 101 may be bent at two or more bend lines 108 at different locations.

[0240] In this embodiment, as shown in FIG. 44, a vapor chamber 101 bent at a right angle at one 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. In the bending region 107, the vapor chamber 101 is bent at a right angle. 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, the configuration of the vapor chamber 101 will be described with reference to Figs. 45 to 58, which show the vapor chamber 101 before bending. The vapor chamber 101 shown in Fig. 44 is obtained by bending the flat vapor chamber 101 shown in Fig. 45.

[0242] As shown in Figures 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 above-mentioned electronic device D. Examples of the working fluids 102a and 102b include pure water, ethanol, methanol, acetone, etc., and mixtures thereof.

[0243] As shown in FIG. 45 and FIG. 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 is hereinafter simply referred to as the wick sheet 130. In the vapor chamber 101 according to the present embodiment, the first sheet 110, the wick sheet 130, and the second sheet 120 are stacked in this order. In the present embodiment, an example in which the wick sheet 130 is composed of one sheet is shown, but the wick sheet 130 may be composed of two or more sheets, and the number of sheets of the wick sheet 130 is arbitrary.

[0244] The vapor chamber 101 shown in FIG. 45 is generally formed in a thin flat plate shape. The planar shape of the vapor chamber 101 before bending is arbitrary, but 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 being 1 cm and the other side being 3 cm, or a square with one side being 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 rectangular shape 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 in 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 the working liquid 102b is evaporated by this heat, and the working vapor 102a is generated. 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 that 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, and the working liquid 102b is generated.

[0248] Here, the plan view is a state in which the vapor chamber 101 is 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 surface that receives heat corresponds to the second sheet outer surface 120b of the second sheet 120 described later, and the surface that releases heat corresponds to the first sheet outer surface 110a of the first sheet 110 described later. The surface that receives heat may correspond to the first sheet outer surface 110a, and the surface that releases heat 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 in the direction indicated by the arrow V1 corresponds to the plan view. In the second region 106, the state viewed in the direction indicated by the 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 the vapor chamber 101 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 FIG. 46 and FIG. 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 limited to this. The alignment holes 112 may 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 to 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 described below is in contact with the second sheet inner surface 120a. As shown in FIG. 46 and FIG. 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 hole 122 has a circular planar shape, but this is not limited to this. Alignment hole 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 FIG. 45 and FIG. 48, the second sheet outer surface recess 123 extends in a direction intersecting with the X direction in a plan view. The second sheet outer surface recess 123 may extend in the Y direction or may extend along the bending line 108. The second sheet outer surface recess 123 may cross the first steam passage 151 or the second steam passage 152 in a plan view. In this embodiment, the second sheet outer surface recess 123 is formed in the entire Y direction of the second sheet 120. In this case, the second sheet outer surface recess 123 extends so as to cross the frame body portion 132, each land portion 133, and each steam passage 151, 152 in a plan view. However, this is not limited to this, and the second sheet outer surface recess 123 does not have to be formed in the entire Y direction of the second sheet 120 as long as it can ensure the bendability of the vapor chamber 101 and the flow path cross-sectional area of ​​each steam passage 151, 152 after bending. 45, the second sheet outer surface recess 123 has a linear shape extending in the Y direction in a 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 shape in which multiple circles are connected together in the Y direction and partially overlap each other in a plan view. In this way, the planar shape of the second sheet outer surface recess 123 is arbitrary.

[0255] As shown in Fig. 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 a groove shape 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. Thus, 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 from the second sheet outer surface 120b of the second sheet 120 in a second sheet etching process described later. As a result, the second sheet outer surface recess 123 may have a wall surface formed in a curved shape as shown in FIG. 49. This wall surface may be curved in a shape that defines the second sheet outer surface recess 123 and 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 is arbitrary 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. Also, for example, as shown in FIG. 52, the cross-sectional shape of the second sheet outer surface recess 123 may be rectangular. Also, for example, the cross-sectional shape of the second sheet outer surface recess 123 may be a trapezoidal shape as shown in Fig. 53. Also, for example, the cross-sectional shape of the second sheet outer surface recess 123 may be a partial circle shape having a width on the inside that is wider than the opening, as shown in Fig. 54. Also, the second sheet outer surface recess 123 may be formed by a method other than etching, and the formation method is arbitrary. For example, the second sheet outer surface recess 123 may be formed by pressing or routing.

[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 about 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 body surface 130a and a second body surface 130b located on the opposite side to the first body surface 130a. A first sheet inner surface 110b of the first sheet 110 contacts the first body surface 130a. A second sheet inner surface 120a of the second sheet 120 contacts the second body surface 130b.

[0260] The first sheet inner surface 110b of the first sheet 110 and the first body surface 130a of the wick sheet 130 may be diffusion bonded. The first sheet inner surface 110b and the first 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 body surface 130b of the wick sheet 130 may be diffusion bonded. The second sheet inner surface 120a and the second body surface 130b may be permanently bonded to each other.

[0262] Note that the term "permanently joined" is not limited to a strict meaning, but is used to mean that the connection is made to an extent that the sealing property of the sealed space 103 can be maintained when the vapor chamber 101 is in operation.

[0263] As shown in FIG. 45, FIG. 55, and FIG. 56, the wick sheet 130 according to the present embodiment includes a frame portion 132 and a plurality of land portions 133. The frame portion 132 defines a steam flow path portion 150, and is formed in a rectangular frame shape along the X direction and the Y direction in a plan view. The land portion 133 is located inside the frame portion 132 in a plan view, and the steam flow path portion 150 is located around the land portion 133. Therefore, the working steam 102a flows around the land portion 133. The frame portion 132 and the land portion 133 are portions that are not etched in a wick sheet etching process described later, and the material of the wick sheet 130 remains. Between the frame portion 132 and the adjacent land portion 133, a first steam passage 151 described later through which the working steam 102a flows is formed. Between the adjacent land portions 133, a second steam passage 152 described later through which the working steam 102a flows is formed.

[0264] The land portion 133 may extend in an elongated shape with the X direction as the longitudinal direction in a plan view. The planar shape of the land portion 133 may be an elongated rectangular shape. The X direction is an example of a first direction, and corresponds to the left-right direction in Figs. 55 and 56. The land portions 133 may be disposed 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 a plan view. The Y direction is a width direction of the land portion 133, and corresponds to the up-down direction in Figs. 55 and 56. The land portions 133 may be located parallel to each other. The direction perpendicular to each of the X direction and the Y direction is defined as the Z direction. The Z direction corresponds to the up-down direction in Figs. 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-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 arranged. 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-down direction in FIG. 44.

[0267] The frame 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. A wall surface 153a of the first vapor flow path recess 153 and a wall surface 154a of the second vapor flow path recess 154 described below 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 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 FIG. 55 and FIG. 56, the steam flow passage section 150 according to the present embodiment may include a first steam passage 151 and a plurality of second steam passages 152. The first steam passage 151 and the second steam passage 152 are each an example of a working fluid passage. The first steam passage 151 is formed between the frame body section 132 and the land section 133. The first steam passage 151 is formed inside the frame body section 132 and continuously outside the land section 133. The planar shape of the first steam passage 151 may be a rectangular frame shape along the X direction and the Y direction. The second steam passage 152 is formed between the land sections 133 adjacent to each other. The planar shape of the second steam passage 152 may be an elongated rectangular shape. The steam flow passage section 150 is divided into the first steam passage 151 and a plurality of second steam passages 152 by the plurality of land sections 133.

[0271] 46, the first steam passage 151 and the second steam passage 152 may extend from the first body surface 130a to the second body surface 130b of the wick sheet 130. In this case, the first steam passage 151 and the second steam passage 152 penetrate from the first body surface 130a to the second body surface 130b. The first steam passage 151 and the second steam passage 152 include a first steam flow path recess 153 provided in the first body surface 130a and a second steam flow path recess 154 provided in the second body surface 130b. The first steam flow path recess 153 and the second steam 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 later. The first vapor flow path recess 153 is formed in a concave shape on the first main body surface 130a. The first vapor flow path recess 153 may have a wall surface 153a formed in a curved shape as shown in FIG. 57. FIG. 57 shows a cross section perpendicular to the X direction. This 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 path 151 that is relatively close to the first sheet 110 and a portion of the second vapor path 152 that is relatively close to the first sheet 110.

[0273] The width w12 of the first steam 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 steam flow path recess 153 is a dimension in the Y direction, and is the dimension of the first steam flow path recess 153 in the first main body surface 130a. The width w12 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 w12 also corresponds to the dimension in the X direction of the portion of the first steam 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 later. The second vapor flow path recess 154 is formed in a concave shape on the second main body surface 130b. The second vapor flow path recess 154 may have a wall surface 154a formed in a curved shape as shown in FIG. 57. 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 vapor path 151 that is relatively close to the second sheet 120 and a portion of the second vapor path 152 that is relatively close to the second sheet 120.

[0275] The width w13 of the second steam 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 steam flow path recess 153 described above. The width w13 of the second steam flow path recess 154 is a dimension in the Y direction, and is the dimension of the second steam 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 steam flow path recess 154 may be equal to the width w12 of the first steam flow path recess 153, or may be different.

[0276] As shown in FIG. 57, a wall surface 153a of the first steam flow path recess 153 and a wall surface 154a 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 where the wall surface 153a of the first steam flow path recess 153 and the wall surface 154a of the second steam flow path recess 154 join together. The ridge line may be formed so as to protrude inward of the steam paths 151 and 152 as shown in FIG. The planar area of ​​the first steam path 151 in this through-portion 134 may be minimized, and the planar area of ​​the second steam path 152 in 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 inwardly of the steam passages 151, 152, as shown in FIG.

[0277] The position of the through-hole 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-hole 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-hole 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-hole 134 defined by a ridge line formed to protrude inward, but are not limited to this. For example, the cross-sectional shapes of first steam passage 151 and second steam passage 152 may be trapezoidal or parallelogrammatic, or may be barrel-shaped.

[0279] The steam flow path portion 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 stream grooves 161, which will be described later, is different from that in FIG.

[0281] Although not shown, a plurality of support parts for supporting the land part 133 on the frame part 132 may be provided in each of the steam passages 151 and 152. Support parts for supporting adjacent land parts 133 may also be provided. These support parts may be provided on both sides of the land part 133 in the X direction, or on both sides of the land part 133 in the Y direction. The support parts may be formed so as not to impede the flow of the working steam 102a diffusing through the steam passage part 150. For example, the support parts 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 part 150 may be formed near the other. This allows the thickness of the support parts to be thinner than the thickness of the wick sheet 130, and prevents the first steam passage 151 and the second steam passage 152 from being divided 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 FIG. 46, FIG. 55, and FIG. 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 the working liquid 102b mainly passes. The above-mentioned working steam 102a may pass through the liquid flow path portion 160. The liquid flow path portion 160 constitutes a part of the above-mentioned sealed space 103, and is in communication with the steam 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 and the like, the liquid flow path portion 160 may be formed on the inner portion of the first main body surface 130a of the frame 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 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 mainstream grooves 161 and a plurality of communication grooves 165. The mainstream grooves 161 and the communication grooves 165 of the liquid flow path section 160 are an example of a first groove. The mainstream grooves 161 and the communication grooves 165 are grooves through which the working fluid 102b passes. The communication grooves 165 communicate with the mainstream 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 passage cross-sectional area so that the working fluid 102b flows mainly by capillary action. The flow passage cross-sectional area of ​​the main grooves 161 is smaller than the flow passage 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 equally spaced apart along the Y direction perpendicular to the X direction. The main grooves 161 may be 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 vapor 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 Y-direction dimension of the mainstream groove 161. The depth h11 of the mainstream groove 161 may be, for example, 3 µm to 300 µm. The depth h11 corresponds to the Z-direction dimension of the mainstream groove 161.

[0288] As shown in FIG. 58, each communication groove 165 extends in a direction different from the X direction. Each communication groove 165 according to the present embodiment extends in the Y direction and is formed perpendicular to the mainstream groove 161. Some communication grooves 165 communicate with adjacent mainstream grooves 161. Other communication grooves 165 communicate with the first steam passage 151 or the second steam passage 152 and 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 passage cross-sectional area so that the working fluid 102b flows mainly by capillary action. The flow passage cross-sectional area of ​​the communication groove 165 is smaller than the flow passage cross-sectional area of ​​the steam passages 151, 152. The communication grooves 165 are spaced apart at predetermined intervals along the X direction. The connecting grooves 165 may be positioned parallel to each other.

[0290] The communication groove 165 is also formed by etching, as described below, in the same manner as the mainstream groove 161. As a result, the communication groove 165 may have a wall surface (not shown) formed in a curved shape similar to that of the mainstream groove 161. The width w16 of the communication groove 165 may be smaller than the width w12 of the first vapor flow path recess 153. The width w16 of the communication groove 165 may be smaller than the width w11 of the land portion 133. As shown in FIG. 58, the width w16 of the communication groove 165 may be equal to the width w15 of the mainstream groove 161. However, the width w16 may be larger or smaller than the width w15. The width w16 means the dimension of the communication groove 165 on the first main body surface 130a. In FIG. 58, the width w16 corresponds to the X-direction dimension of the communication groove 165. The depth of the communication groove 165 may be equal to the depth h11 of the mainstream groove 161. However, the depth of the connecting groove 165 may be deeper or shallower than the depth h11.

[0291] 58, the liquid flow path portion 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 with its longitudinal direction being the X direction in a plan view. A main stream groove 161 is interposed between adjacent protrusions 164 in the Y direction. A communication groove 165 is interposed between adjacent protrusions 164 in the X direction.

[0292] The protrusions 164 are portions that are not etched in a wick sheet etching process 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 convex portions 164 are positioned in a staggered manner. More specifically, the convex portions 164 of the convex portion rows 163 adjacent to each other in the Y direction are positioned at positions shifted from each other in the X direction. This shift amount may be half the arrangement pitch of the convex portions 164 in the X direction. The width w17 of the convex portions 164 may be, for example, 5 μm to 500 μm. The width w17 means the dimension of the convex portions 164 on the first main body surface 130a. In FIG. 58, the width w17 corresponds to the Y direction dimension of the convex portions 164. The positions of the convex portions 164 are not limited to being staggered, and may be arranged in parallel. In this case, the convex portions 164 of the convex portion rows 163 adjacent to each other in the Y direction are positioned at the same position in the X direction.

[0294] Incidentally, 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 a good thermal conductivity to the extent that the heat dissipation efficiency of the vapor chamber 101 can be ensured. 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. Therefore, the vapor chamber 101 can 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 thick. Therefore, the vapor chamber 101 can 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 the present 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 limited to the above, 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 suppressed. The thickness t13 of the second sheet 120 may be set to be the same 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 setting the thickness t14 of the wick sheet 130 to 50 μm or more, the vapor channel portion 150 can be properly secured. Therefore, the vapor chamber 101 can function properly. On the other hand, by setting the thickness t14 to 400 μm or less, the thickness t11 of the vapor chamber 101 can be prevented from becoming thick. Therefore, the vapor chamber 101 can be made thin. 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, the vapor chamber 101 according to the present embodiment includes a bending region 107. In the bending region 107, the vapor chamber 101 is bent along a bending line 108 extending in a direction intersecting the X direction in a plan view. As shown in FIG. 44 and FIG. 45, the bending line 108 according to the present 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. The bending line 108 crosses the frame body portion 132, the land portion 133, the first steam passage 151, and the second steam passage 152. This can suppress deformation of the first sheet 110 into each of the steam passages 151 and 152, and can suppress deformation of the second sheet 120 into each of the steam passages 151 and 152. The flow path cross-sectional area of ​​the first steam passage 151 and the second steam passage 152 can be secured. The first region 105, the second region 106, and the curved region 107 may be divided 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 divided by a boundary line extending in the Y direction in a plan view.

[0300] 45 and 59, the above-mentioned 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. One example of a passage bend 157 is shown in Figure 59. 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 of forming the second sheet 120 by etching, and a wick sheet etching step of forming the wick sheet 130 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 fixing process, the first sheet 110, the wick sheet 130, and the second sheet 120 are temporarily fixed. For example, the sheets 110, 120, and 130 may be temporarily fixed 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, as an injection step, the sealed space 103 is evacuated and the hydraulic fluid 102b is injected into the sealed space 103 from an injection part 104 (see FIG. 45).

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

[0309] After the sealing step, the first sheet 110, the second sheet 120, and the wick sheet 130 may be bent as a bending step. 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 bending. Both ends in the X direction of each sheet 110, 120, and 130 in the X direction are gripped, and each sheet 110, 120, and 130 is bent at a desired angle. As a result, the bent vapor chamber 101 shown in FIG. 44 is obtained, and the bent region 107 of the vapor chamber 101 is formed. The bending step may be performed between the joining step and the injection step.

[0310] In this embodiment, a second sheet outer surface recess 123 is formed on second sheet outer surface 120b of second sheet 120 located on the inside of the bend. In the bending process, vapor chamber 101 may be bent at the position where second sheet outer surface recess 123 is formed. Vapor chamber 101 may be bent so that bend line 108 is aligned with the direction in which second sheet outer surface recess 123 extends. 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 cover portion 124 (see FIG. 57) that covers each of 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. For this reason, displacement of the second sheet lid portion 124 towards the inside of the bend is restricted, and the second sheet lid portion 124 tends to enter into 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, the second sheet outer surface recess 123 is formed on the second sheet outer surface 120b in the bending region 107. This makes it possible to absorb the compressive stress acting on the second sheet lid portion 124 when it is bent, and makes it possible to prevent the second sheet lid portion 124 from entering into the second steam flow path recess 154.

[0312] In this manner, the vapor chamber 101 according to the present 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 surface of the sealed space 103 due to its surface tension. More specifically, the working liquid 102b adheres to the wall surface 153a of the first vapor flow path recess 153, the wall surface 154a of the second vapor flow path recess 154, the wall surface 162 of the main flow path groove 161 of the liquid flow path section 160, and the wall surface of the communication 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 102 b may also adhere to the portions of the second sheet inner surface 120 a of the second sheet 120 that are exposed to the second vapor flow path recess 154 , the main groove 161 , and the connecting groove 165 .

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

[0317] Then, the working steam 102a in each of the steam passages 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 mainly dissipating heat 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 the working liquid 102b is generated. The generated working liquid 102b adheres to the wall surfaces 153a, 154a of the vapor flow path recesses 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 main groove 161 (see the dashed arrow in FIG. 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 manner, 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 propulsive 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 if the evaporation region SR is located above the vapor chamber 101, the working fluid 102b is transported by the capillary action.

[0319] In the liquid flow path section 160, each mainstream groove 161 communicates with the adjacent other mainstream grooves 161 via the corresponding communication grooves 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 evaporated by receiving heat from the electronic device D again. 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 in each of the vapor flow path recesses 153 and 154, and a part of the working vapor 102a can diffuse through the passage bent portion 157. In this way, the working fluids 102a and 102b circulate in the sealed space 103 while repeatedly changing phases, that is, evaporating and condensing. This causes the heat of the electronic device D to be diffused and released. As a result, the electronic device D is cooled.

[0321] Thus, according to this embodiment, in the bending region 107, the second sheet outer surface recess 123 is located on the second sheet outer surface 120b of the second sheet 120. This makes it possible to absorb the stress acting on the second sheet 120 when the vapor chamber 101 is bent, and to prevent the second sheet 120 in the bending region 107 from entering the first steam passage 151 or the second steam passage 152. This makes it possible to ensure the flow path cross-sectional area of ​​the first steam passage 151 and the second steam passage 152, and to prevent the flow of the working steam 102a in the bending region 107 from being obstructed. As a result, even when the vapor chamber 101 is bent, the heat dissipation efficiency of the vapor chamber 101 can be improved. In addition, since the second sheet outer surface recess 123 can be easily seen, it can be used as a mark for the bending position of the vapor chamber 101 before bending. This makes it possible to improve the bending workability.

[0322] Furthermore, according to this embodiment, second sheet 120 is located inside 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 steam passage 151 or second steam 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 makes it possible to effectively absorb the 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. Also, vapor chamber 101 can be easily bent along bending line 108.

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

[0325] According to the present embodiment, the bending line 108 extends in the Y direction 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. This makes it possible to suppress deformation of the first sheet 110 entering each of the steam passages 151 and 152 in the bending region 107, and also suppress deformation of the second sheet 120 entering each of the steam passages 151 and 152. This makes it possible to ensure the flow path cross-sectional areas of the first steam passage 151 and the second steam passage 152, and to suppress obstruction of the flow of the working steam 102a in the bending region 107.

[0326] In the above-described embodiment, an example in which 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 has been described. However, the present invention 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 above-described liquid flow path portion 160. 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 the flow path cross-sectional area of ​​the groove of the liquid flow path portion 160, or may be larger than the flow path cross-sectional area of ​​the groove of the liquid flow path portion 160. In addition, when the liquid flow path portion is formed on the second main body surface 130b, the liquid flow path portion 160 may not 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 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 lattice 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. Moreover, in the example shown in Fig. 60, adjacent second sheet outer surface recesses 123 are spaced apart, so that it is possible to prevent the mechanical strength of vapor chamber 101 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. For example, as shown in FIG. 62, the second sheet outer surface recess 123 may have a rectangular planar shape. Also, 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 direction and the Y direction, and opposing corners of the rectangle are aligned with the bending line 108. In the example shown in FIG. 63, the second sheet outer surface recess 123 is arranged in a lattice shape. Also, 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] 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, the tensile stress acting on the first sheet 110 when the vapor chamber 101 is bent 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. Also, the second sheet 120 on which the second sheet outer surface recess 123 is formed may be disposed on the outer side of the bend, and the first sheet 110 on which the first sheet outer surface recess 113 is not formed may be disposed on the inner side of the bend.

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

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

[0335] (Sixteenth 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 16th embodiment shown in Figures 67 and 68 is different 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 15th embodiment shown in Figures 42 to 66. In Figures 67 and 68, the same parts as those of the 15th embodiment shown in Figures 42 to 66 are denoted 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 plan view. The bending line 108 shown in Figures 67 and 68 extends in a direction inclined in the X direction and also in a direction inclined in the Y direction. The bending line 108 according to this embodiment also extends in a direction intersecting the X direction in 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 may be spaced apart at equal intervals in the X direction. The second sheet outer surface recesses 123 may be positioned parallel to each other.

[0339] Thus, according to this embodiment, the bend line 108 extends in a direction inclined toward the X direction. This makes it possible to prevent the second sheet 120 in the bent region 107 from entering the first steam passage 151 or the second steam passage 152 even when the vapor chamber 101 is bent along the bend line 108 extending in a direction inclined toward the X direction. This makes it possible to ensure the flow path cross-sectional areas of the first steam passage 151 and the second steam passage 152, and to prevent the flow of the working steam 102a in the bent 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.

[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 similarly to the examples shown in Figs. 60 to 63.

[0341] (Seventeenth 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 in the fifteenth embodiment shown in Figures 42 to 66 are denoted by the same reference numerals and detailed description thereof will be omitted.

[0343] In the vapor chamber 101 according to the present embodiment, as shown in FIG. 69, the 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 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 on the opposite side to 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 beyond 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 a wall surface formed in a curved shape, as shown in Fig. 69. This wall surface defines the land recesses 137 and may be curved in a shape that bulges toward the first main body surface 130a.

[0349] 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 Y-direction dimension of the land recess 137. The depth h13 of the land recess 137 may be, for example, 20 μm to 120 μm. The depth h13 corresponds to the Z-direction dimension of the land recess 137.

[0350] Thus, according to this embodiment, land recess 137 that does not communicate with steam passages 151, 152 is located on second main body surface 130b of land portion 133, and land recess 137 overlaps second sheet 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 on both sides in the X direction than the second sheet outer surface recess 123. This allows the rigidity of the land portion 133 to be reduced even in the vicinity of the second sheet outer surface recess 123. Therefore, when the vapor chamber 101 is bent, the land portion 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 FIG. 67 and FIG. 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-mentioned embodiments and modifications, and can be embodied by modifying the components without departing from the spirit of the invention. In addition, various inventions can be formed by appropriately combining the multiple components disclosed in the above-mentioned embodiments and modifications. Some components may be deleted from all the components shown in the above-mentioned embodiments and modifications.

Claims

[Claim 1] A vapor chamber in which a working fluid is sealed, A main sheet; 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 communicating 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, a plurality of first sheet grooves provided on the first sheet inner surface, and a plurality of first sheet communication grooves provided on the first sheet inner surface and communicating the first sheet grooves adjacent to each other, A vapor chamber, wherein the first seat groove and the first seat connecting groove are provided at a position overlapping with the vapor passage in a plan view.

Images