JP2018115813A - Vapor chamber, metal sheet assembly for vapor chamber, and manufacturing method of vapor chamber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor chamber which can inhibit deformation.SOLUTION: A vapor chamber 1 according the invention includes: a lower metal sheet 10 to which a cooled device D is attached; and an upper metal sheet 20 provided on the lower metal sheet 10 and forming a sealed space 3 with the lower metal sheet 10. Further, the vapor chamber 1 includes deformation inhibition members 31, 32 which are provided on at least one of a lower surface 10b of the lower metal sheet 10 and an upper surface of the upper metal sheet and inhibit deformation of the vapor chamber 1.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vapor chamber having a sealed space in which a working fluid is sealed, a metal sheet combination for a vapor chamber, and a method for manufacturing a vapor chamber.

  A vapor chamber (also referred to as a heat pipe) is used for cooling devices that generate heat, such as a central processing unit (CPU) used in mobile terminals such as mobile terminals and tablet terminals (for example, Patent Documents). 1). A working fluid is sealed in the vapor chamber, and the working fluid absorbs the heat of the device and releases it to the outside, thereby cooling the device.

  More specifically, the working fluid in the vapor chamber receives heat from the device at a portion close to the device (evaporation unit) and evaporates into vapor, and then the vapor moves to a position away from the evaporation unit. Cooled and condensed into a liquid state. The working fluid that has become liquid passes through the liquid flow path in the vapor chamber, is transported to the evaporation unit, and is evaporated again by receiving heat in the evaporation unit. In this way, the working fluid recirculates in the vapor chamber while repeating phase change, that is, evaporation and condensation, thereby moving the heat of the device and improving the heat radiation efficiency.

JP 2007-315745 A

  The vapor chamber may be formed of copper or copper alloy having good thermal conductivity in order to enhance the heat dissipation effect. For this reason, when the thickness of the vapor chamber is reduced in order to make the mobile terminal compact, the rigidity of the vapor chamber can be a problem. For example, when the vapor chamber is installed in a mobile terminal or the like, if an excessive force is applied to the vapor chamber, the vapor chamber may be deformed. Therefore, careful handling is required at the time of installation. In addition, the sealed space is evacuated before injecting the working fluid into the sealed space of the vapor chamber. In this case as well, there is a possibility that the vapor chamber is deformed due to a differential pressure inside and outside the vapor chamber. In addition, when other components are joined to the vapor chamber by soldering, the vapor chamber may be deformed by thermal expansion.

  Further, as described above, when the vapor chamber is operated, a part of the vapor chamber is in contact with the liquid working fluid, and the other part is in contact with the vapor of the working fluid. As a result, a temperature distribution is generated in the vapor chamber, and the elongation due to thermal expansion of each portion is different. For this reason, there is also a problem that deformation due to warpage occurs in the vapor chamber.

  If the vapor chamber is deformed in this way, the flow area of the flow path for the working fluid vapor or the liquid working fluid in the sealed space is reduced, and the vapor chamber may not operate normally.

  The present invention has been made in consideration of such points, and an object thereof is to provide a vapor chamber, a metal sheet assembly for a vapor chamber, and a method for manufacturing a vapor chamber that can suppress deformation.

  The present invention is a vapor chamber that has a sealed space filled with hydraulic fluid and cools a cooled device, and is provided on a lower metal sheet to which the cooled device is attached, and on the lower metal sheet. The upper metal sheet that forms the sealed space between the lower metal sheet and at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet, the deformation of the vapor chamber. There is provided a vapor chamber comprising a deformation suppressing member for suppressing.

  In the above-described vapor chamber, the deformation suppressing member is provided on the lower surface of the lower metal sheet, and the bending strength of the deformation suppressing member provided on the lower surface of the lower metal sheet is lower than the lower metal sheet. You may make it larger than the bending strength of a metal sheet.

  Further, in the vapor chamber described above, the front deformation suppressing member is provided on the lower surface of the lower metal sheet, and the thermal expansion coefficient of the deformation suppressing member provided on the lower surface of the lower metal sheet is You may make it larger than the thermal expansion coefficient of a lower side metal sheet.

  In the above-described vapor chamber, the deformation suppressing member is provided on the upper surface of the upper metal sheet, and the bending strength of the deformation suppressing member provided on the upper surface of the upper metal sheet is determined by the upper metal sheet. You may make it larger than bending strength.

  In the above-described vapor chamber, the deformation suppressing member is provided on the upper surface of the upper metal sheet, and the coefficient of thermal expansion of the deformation suppressing member provided on the upper surface of the upper metal sheet is the upper metal sheet. The coefficient of thermal expansion may be smaller.

  In the vapor chamber described above, the deformation suppressing member may be formed of stainless steel.

  In the vapor chamber described above, the deformation suppressing member may include a plating layer.

  In the above-described vapor chamber, the lower metal sheet and the upper metal sheet may be made of copper or a copper alloy.

  The present invention also provides a metal sheet assembly for a vapor chamber for a vapor chamber for cooling a device to be cooled, which has a sealed space filled with a working fluid, the vapor chamber metal sheet, and the vapor chamber There is provided a metal sheet assembly for a vapor chamber, comprising: a deformation suppressing member provided on one surface of the metal sheet for suppressing deformation of the vapor chamber.

  Further, the present invention is a method of manufacturing a vapor chamber formed between a lower metal sheet and an upper metal sheet, which has a sealed space in which a working fluid is enclosed, and cools a device to be cooled. A step of preparing the lower metal sheet and the upper metal sheet to which a device to be cooled is attached; joining the lower metal sheet and the upper metal sheet; and the lower metal sheet and the upper metal sheet; Forming the sealed space between, and joining the lower metal sheet and the upper metal sheet to at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet, There is provided a method of manufacturing a vapor chamber, comprising: a step of providing a deformation suppressing member that suppresses deformation of the vapor chamber; and a step of enclosing the hydraulic fluid in the sealed space.

  Further, the present invention is a method of manufacturing a vapor chamber formed between a lower metal sheet and an upper metal sheet, which has a sealed space in which a working fluid is enclosed, and cools a device to be cooled. Deformation of the vapor chamber on at least one of the step of preparing the lower metal sheet and the upper metal sheet to which a device to be cooled is attached, and the lower surface of the lower metal sheet and the upper surface of the upper metal sheet A step of providing a deformation suppressing member for suppressing the deformation, and joining the lower metal sheet and the upper metal sheet, each having at least one of the deformation suppressing member, between the lower metal sheet and the upper metal sheet A method for manufacturing a vapor chamber is provided, comprising: forming the sealed space in a step; and sealing the hydraulic fluid in the sealed space.

  Further, in the above-described method for manufacturing a vapor chamber, in the step of providing the deformation suppressing member, the deformation suppressing member is formed on an adhesive on at least one of a lower surface of the lower metal sheet and an upper surface of the upper metal sheet, They may be joined by any one of brazing, soldering, diffusion bonding, and laser welding.

  In the vapor chamber manufacturing method described above, in the step of providing the deformation suppressing member, the deformation suppressing member is formed by plating on at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet. It may be formed.

  According to the present invention, deformation can be suppressed.

FIG. 1 is a top view showing a vapor chamber according to a first embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG. 3 is a cross-sectional view taken along line BB in FIG. 4 is a cross-sectional view taken along the line CC of FIG. FIG. 5 is a top view showing the lower metal sheet of FIG. FIG. 6 is a bottom view showing the upper metal sheet of FIG. FIG. 7 is a front view showing a measuring instrument used for measuring the bending strength. FIG. 8 is a view for explaining a bending strength measurement process using the measuring instrument of FIG. FIG. 9 is a view for explaining a preparation process for the lower metal sheet in the method for manufacturing the vapor chamber of FIG. 1. FIG. 10 is a view for explaining a half etching process of the lower metal sheet in the method of manufacturing the vapor chamber of FIG. FIG. 11 is a view for explaining a wick attachment process in the method of manufacturing the vapor chamber of FIG. 1. FIG. 12 is a diagram for explaining a temporary fixing step in the method for manufacturing the vapor chamber of FIG. 1. FIG. 13 is a view for explaining a diffusion bonding step in the method of manufacturing the vapor chamber of FIG. FIG. 14 is a view for explaining a joining step of the deformation suppressing member in the method of manufacturing the vapor chamber of FIG. FIG. 15 is a diagram for explaining a hydraulic fluid sealing step in the vapor chamber manufacturing method of FIG. 1. FIG. 16 is a view for explaining a modification of the method of manufacturing the vapor chamber of FIG.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale and the vertical / horizontal dimensional ratio are appropriately changed and exaggerated from those of the actual ones.

  An embodiment of the present invention will be described with reference to FIGS. The vapor chamber 1 in the present embodiment has a sealed space 3 in which a working fluid 2 is enclosed, and the working fluid 2 in the sealed space 3 repeats a phase change, whereby a mobile terminal such as a portable terminal or a tablet terminal. This is a device for cooling a device D (cooled device) that generates heat, such as a central processing unit (CPU) used in the above. The vapor chamber 1 is generally formed in a thin flat plate shape.

  As shown in FIGS. 1 to 4, the vapor chamber 1 includes a lower metal sheet 10 and an upper metal sheet 20 provided on the lower metal sheet 10. The lower metal sheet 10 and the upper metal sheet 20 each correspond to a vapor chamber metal sheet. A device D, which is an object to be cooled, is attached to a lower surface 10b of the lower metal sheet 10 (particularly, a lower surface of an evaporation unit 11 described later) via a lower deformation suppressing member 31 described later. Between the lower metal sheet 10 and the upper metal sheet 20, a sealed space 3 in which the hydraulic fluid 2 is enclosed is formed. Examples of the working fluid 2 include pure water, ethanol, methanol, acetone and the like. The lower metal sheet 10 and the upper metal sheet 20 are bonded by diffusion bonding described later. In the form shown in FIG. 1, the lower metal sheet 10 and the upper metal sheet 20 are both formed in a rectangular shape in plan view, but are not limited thereto. Here, the plan view means a direction in which the vapor chamber 1 receives heat from the device D (lower surface 10b of the lower metal sheet 10) and a surface that releases the received heat (upper surface 20b of the upper metal sheet 20). This corresponds to, for example, a state where the vapor chamber 1 is viewed from above (see FIG. 1) or a state viewed from below. When the vapor chamber 1 is installed in the mobile terminal, the vertical relationship between the lower metal sheet 10 and the upper metal sheet 20 may be broken depending on the attitude of the mobile terminal. However, in the present embodiment, the metal sheet on the liquid phase side that receives heat from the device D is referred to as the lower metal sheet 10, and the metal sheet on the gas phase side that releases the received heat is referred to as the upper metal sheet 20. To do.

  As shown in FIGS. 1 to 5, the lower metal sheet 10 is provided on the evaporation section 11 where the working fluid 2 evaporates to generate steam and the upper surface 10 a (the surface on the upper metal sheet 20 side). And a lower channel recess 12 formed in a rectangular shape as viewed. Of these, the lower channel recess 12 constitutes a part of the above-described sealed space 3, and mainly evaporates the working fluid 2 (see FIGS. 2 to 4) condensed from the vapor generated in the evaporation unit 11. It is configured to be transported to the part 11. The evaporation unit 11 is a part that receives heat from the device D attached to the lower surface 10 b of the lower metal sheet 10 and evaporates the hydraulic fluid 2 in the sealed space 3. For this reason, the term “evaporating section 11” is not limited to a portion overlapping the device D, but is used as a concept including a portion where the hydraulic fluid 2 can be evaporated without overlapping the device D. Here, the evaporating part 11 can be provided at an arbitrary position of the lower metal sheet 10, but FIG. 5 shows an example provided at the central part of the lower metal sheet 10. In this case, the operation of the vapor chamber 1 can be stabilized regardless of the attitude of the mobile terminal in which the vapor chamber 1 is installed.

  In the present embodiment, as shown in FIGS. 1, 2, 4, and 5, the lower metal sheet 10 has a lower flow path recess 12, and a bottom surface 12 a (described later) of the lower flow path recess 12. A plurality of lower flow path protrusions 13 protruding upward (in a direction perpendicular to the bottom surface 12a) are provided. In the present embodiment, an example in which the lower channel protrusion 13 is formed as a cylindrical boss is shown, and includes an upper surface 13a and side surfaces. Each of the lower flow path protrusions 13 extends along the longitudinal direction of the vapor chamber 1 (the left-right direction in FIGS. 1 and 5) and is spaced apart at equal intervals. Further, the lower flow path protruding portion 13 is also disposed along the transverse direction of the vapor chamber 1 (the lateral direction orthogonal to the longitudinal direction, the vertical direction in FIGS. 1 and 5). A bottom surface 12a of the lower flow path recess 12 is formed around the lower flow path protrusion 13 arranged in this manner. In this way, the hydraulic fluid 2 is configured to flow around the lower flow path protruding portion 13, and the flow of the hydraulic fluid 2 is prevented from being hindered. Further, the lower flow path protrusion 13 is disposed so as to overlap with a corresponding upper flow path protrusion 22 (described later) of the upper metal sheet 20 in plan view, thereby improving the mechanical strength of the vapor chamber 1. ing.

  As shown in FIGS. 2 to 4, a wick W is provided in a portion of the lower flow path recess 12 excluding the evaporation section 11. Here, the wick is a member that is formed of, for example, a metal mesh pressed with an indefinite shape of a copper wire or a porous sintered body and exhibits a capillary action. The wick W is configured to exert a propulsive force toward the evaporation unit 11 to the hydraulic fluid 2 in the lower flow path recess 12 by exerting a capillary action. Thus, the working fluid 2 in the lower flow path recess 12 condensed from the vapor is smoothly transported toward the evaporation section 11. The wick W may be provided in the entire area of the bottom surface 12a of the lower flow path recess 12. The wick W provided in the evaporation unit 11 in the bottom surface 12a can increase the heat exchange area between the liquid working fluid 2 and the heat received from the device D and contribute to improving the thermal efficiency. Further, the wick W provided around the evaporation unit 11 in the bottom surface 12 a can contribute to the effective transportation of the liquid working fluid 2 to the evaporation unit 11. Further, the wick W is attached so as to be fitted between the lower channel protrusions 13 of the lower channel recess 12. Further, the height of the wick W can be set arbitrarily as long as the heat exchange area in the evaporation unit 11 can be increased or the flow rate of the working fluid 2 toward the evaporation unit 11 can be secured by capillary action.

  As shown in FIGS. 4 and 5, a lower peripheral wall 14 is provided at the peripheral edge of the lower metal sheet 10. The lower peripheral wall 14 is formed so as to surround the sealed space 3, particularly the lower flow path recess 12, and defines the sealed space 3. Further, lower alignment holes 15 for positioning the lower metal sheet 10 and the upper metal sheet 20 are provided at four corners of the lower peripheral wall 14 in plan view.

  In the present embodiment, the upper metal sheet 20 has the same structure as the lower metal sheet 10. That is, the vapor chamber 1 according to the present embodiment is configured such that when the lower metal sheet 10 is turned upside down, the upper metal sheet 20 is formed, and two metal sheets having the same structure as the lower metal sheet 10 are produced. Thus, one of the two is turned upside down and joined together. Hereinafter, the configuration of the upper metal sheet 20 will be described in more detail.

  As shown in FIGS. 1 to 4 and 6, the upper metal sheet 20 has an upper flow path recess 21 provided on the lower surface 20 a (surface on the lower metal sheet 10 side). The upper channel recess 21 constitutes a part of the sealed space 3 and is mainly configured to diffuse and cool the steam generated in the evaporation unit 11. More specifically, the vapor in the upper flow path recess 21 diffuses in a direction away from the evaporation unit 11, and most of the vapor is transported to the peripheral portion having a relatively low temperature. As shown in FIGS. 2 and 3, a housing member H constituting a part of a housing of a mobile terminal or the like is disposed on the upper surface 20 b of the upper metal sheet 20 via an upper deformation suppressing member 32 described later. . Thereby, the steam in the upper flow path recess 21 is cooled by the outside air via the upper metal sheet 20, the upper deformation suppressing member 32 and the housing member H.

  In the present embodiment, as shown in FIGS. 1 and 6, the ceiling surface 21 a of the upper channel recess 21 (when the upper metal sheet 20 is inverted upside down in the upper channel recess 21 of the upper metal sheet 20. Are provided with a plurality of upper channel protrusions 22 that project downward (in a direction perpendicular to the ceiling surface 21a) from the bottom of the upper channel recess 21. In the present embodiment, an example in which the upper channel protrusion 22 is formed as a cylindrical boss is shown, and includes a lower surface 22a and side surfaces. Moreover, each upper flow path protrusion part 22 is extended along the longitudinal direction of the vapor chamber 1, and is spaced apart at equal intervals. Further, the upper flow path protrusion 22 is disposed along the transverse direction of the vapor chamber 1. A ceiling surface 21 a of the upper channel recess 21 (a surface corresponding to the bottom surface 12 a of the lower channel recess 12) is formed around the upper channel protrusion 22 arranged in this manner. Thus, it is comprised so that the vapor | steam of the working fluid 2 may flow around the upper side flow-path protrusion part 22, and it suppresses that the flow of a vapor | steam is prevented. Further, the upper channel protrusions 22 are arranged so as to overlap the corresponding lower channel protrusions 13 of the lower metal sheet 10 in plan view, thereby improving the mechanical strength of the vapor chamber 1. .

  As shown in FIGS. 4 and 6, an upper peripheral wall 23 is provided at the peripheral edge of the upper metal sheet 20. The upper peripheral wall 23 is formed so as to surround the sealed space 3, particularly the upper flow path recess 21, and defines the sealed space 3. Further, upper alignment holes 24 for positioning the lower metal sheet 10 and the upper metal sheet 20 are provided at the four corners of the upper peripheral wall 23 in plan view. That is, each upper alignment hole 24 is disposed so as to overlap each lower alignment hole 15 described above during temporary fixing, which will be described later, and is configured such that the lower metal sheet 10 and the upper metal sheet 20 can be positioned. .

  Such lower metal sheet 10 and upper metal sheet 20 are preferably permanently joined to each other by diffusion bonding. More specifically, as shown in FIGS. 2 to 4, the upper surface 14a of the lower peripheral wall 14 of the lower metal sheet 10 and the lower surface 23a of the upper peripheral wall 23 of the upper metal sheet 20 are in contact with each other. The side peripheral wall 14 and the upper peripheral wall 23 are joined to each other. Thus, a sealed space 3 in which the hydraulic fluid 2 is sealed is formed between the lower metal sheet 10 and the upper metal sheet 20. Further, the upper surface 13 a of the lower channel protrusion 13 of the lower metal sheet 10 and the lower surface 22 a of the upper channel protrusion 22 of the upper metal sheet 20 come into contact with each other and correspond to each lower channel protrusion 13. The upper flow path protrusion 22 is joined to each other. Thereby, the mechanical strength of the vapor chamber 1 is improved. In particular, since the lower flow path protrusion 13 and the upper flow path protrusion 22 according to the present embodiment are arranged at equal intervals, the mechanical strength at each position of the vapor chamber 1 can be equalized. The lower metal sheet 10 and the upper metal sheet 20 may be joined by other methods such as brazing as long as they can be permanently joined instead of diffusion joining.

  As shown in FIGS. 1, 5, and 6, the vapor chamber 1 includes an injection portion 4 that injects the working fluid 2 into the sealed space 3 at one of the pair of end portions in the longitudinal direction. In addition. The injection portion 4 includes a lower injection protrusion 16 that protrudes from the end surface of the lower metal sheet 10, and an upper injection protrusion 25 that protrudes from the end surface of the upper metal sheet 20. Among these, the lower injection channel recess 17 is formed on the upper surface of the lower injection projection 16, and the upper injection channel recess 26 is formed on the lower surface of the upper injection projection 25. The lower injection channel recess 17 communicates with the lower channel recess 12, and the upper injection channel recess 26 communicates with the upper channel recess 21. The lower injection channel recess 17 and the upper injection channel recess 26 form an injection channel for the working fluid 2 when the lower metal sheet 10 and the upper metal sheet 20 are joined. The hydraulic fluid 2 is injected into the sealed space 3 through the injection channel. In the present embodiment, an example in which the injection portion 4 is provided at one end portion of the pair of end portions in the longitudinal direction of the vapor chamber 1 is shown, but the present invention is not limited to this. Absent.

  By the way, the material used for the lower metal sheet 10 and the upper metal sheet 20 is not particularly limited as long as the material has good thermal conductivity. For example, the lower metal sheet 10 and the upper metal sheet 20 are made of copper. Alternatively, it is preferably formed of a copper alloy. Thereby, the thermal conductivity of the lower metal sheet 10 and the upper metal sheet 20 can be increased. For this reason, the heat dissipation efficiency of the vapor chamber 1 can be increased. Further, the thickness T0 of the vapor chamber 1 excluding the lower deformation suppressing member 31 and the upper deformation suppressing member 32 described later is 0.1 mm to 1.0 mm. The thickness T1 of the lower metal sheet 10 and the thickness T2 of the upper metal sheet 20 are half the thickness of the vapor chamber 1 excluding the deformation suppressing members 31 and 32 in order to improve the handling. It is preferred to be equal.

  Next, the lower deformation suppressing member 31 and the upper deformation suppressing member 32 will be described with reference to FIGS. 1 to 4, 7, and 8.

  As shown in FIGS. 1 to 4, a deformation suppressing member that suppresses deformation of the vapor chamber 1 is provided on the lower surface 10 b of the lower metal sheet 10 and the upper surface 20 b of the upper metal sheet 20. In the present embodiment, the deformation suppressing member provided on the lower surface 10b of the lower metal sheet 10 is referred to as a lower deformation suppressing member 31, and the deformation suppressing member provided on the upper surface 20b of the upper metal sheet 20 is referred to as the upper deformation suppressing member. 32. When the vapor chamber 1 is installed in a housing such as a mobile terminal, the lower deformation suppressing member 31 is interposed between the lower surface 10b of the lower metal sheet 10 and the device D that is an object to be cooled. The upper deformation suppressing member 32 is interposed between the upper surface 20b of the upper metal sheet 20 and the housing member H when the vapor chamber 1 is installed in a housing such as a mobile terminal. Further, in the present embodiment, the lower deformation suppressing member 31 and the upper deformation suppressing member 32 are formed in a flat plate shape and a rectangular shape in plan view, and the lower surface 10b and the upper metal of the lower metal sheet 10 are formed. The sheet 20 is provided over the entire area of the upper surface 20b. However, the shape of the lower deformation suppressing member 31 and the upper deformation suppressing member 32 may be arbitrary as long as the deformation of the vapor chamber 1 can be suppressed. Although the thickness T3 of the lower deformation suppressing member 31 and the thickness T4 of the upper deformation suppressing member 32 depend on the respective strengths, they can be arbitrary as long as the deformation of the vapor chamber 1 can be suppressed. For example, it can be 0.1 mm to 0.15 mm.

  The bending strength of the lower deformation suppressing member 31 is preferably larger than the bending strength of the lower metal sheet 10. Thereby, the lower metal sheet 10 and the upper metal sheet 20 can be effectively reinforced by the lower deformation suppressing member 31. Moreover, it is preferable that the bending strength of the upper deformation suppressing member 32 is larger than the bending strength of the upper metal sheet 20. Thereby, the lower metal sheet 10 and the upper metal sheet 20 can be effectively reinforced by the upper deformation suppressing member 32. Here, the term bending strength is used to mean the bending strength obtained by the three-point bending test method specified below.

  As a measuring instrument used for measuring the bending strength, a combination of a tensile testing machine (for example, Autograph AGS-H manufactured by Shimadzu Corporation) and a three-point bending test jig prepared for a three-point bending test is used. Use. That is, as shown in FIG. 7, the measuring instrument 50 includes an indenter 52 that presses the test piece 51 from above the test piece 51 and a pair of supports 53 that support the test piece 51 from below. The indenter 52 is formed in a rod shape so as to extend along the test piece 51 in a direction perpendicular to the paper surface of FIG. The radius R of the front-end | tip part 52a which contact | connects the test piece 51 among this indenter 52 shall be 1.5 mm. The dimensions of the indenter 52 and the support 53 in the depth direction of FIG. 7 are about 100 mm. The distance L1 between the pair of support tools 53 is 100 mm.

  The test piece 51 to be measured is formed in a rectangular flat plate shape. The length L2 of the test piece 51 is about 150 mm, the width of the test piece 51 (the dimension of the test piece 51 in the depth direction of FIG. 7) is about 75 mm, and the thickness T5 of the test piece 51 is about 0.3 mm. Then, three such test pieces 51 are prepared. Note that the alignment of the test specimen 51, the indenter 52, and the support tool 53 to be measured is visually performed so that the respective centers coincide.

  At the time of measurement, as shown in FIG. 8, first, both end portions of the test piece 51 are placed on the support 53. At this time, both end portions of the test piece 51 are merely placed without being restrained with respect to the support tool 53. Next, the indenter 52 is brought into contact with the upper surface of the test piece 51. Subsequently, the indenter 52 is lowered from the contact point with the test piece 51 to 30 mm at a constant lowering speed (0.5 mm / s). Thereafter, the indenter 52 is raised and the indenter 52 is pulled away from the test piece 51. While the indenter 52 is being lowered, the maximum load applied to the indenter 52 is measured. And the maximum load is similarly measured with the three test pieces 51, and the average value of the obtained maximum loads is set as the bending strength according to the present embodiment.

  In addition, the thermal expansion coefficient of the lower deformation suppressing member 31 is preferably larger than the thermal expansion coefficient of the lower metal sheet 10. In this case, during the operation of the vapor chamber 1, it is possible to increase the elongation due to the thermal expansion of the lower metal sheet 10, where the elongation due to the thermal expansion can be smaller than that of the upper metal sheet 20.

  The thermal expansion coefficient of the upper deformation suppressing member 32 is preferably smaller than the thermal expansion coefficient of the upper metal sheet 20. In this case, during the operation of the vapor chamber 1, it is possible to reduce the elongation due to the thermal expansion of the upper metal sheet 20 that can be larger than the lower metal sheet 10 due to the thermal expansion.

  By the way, the material used for the lower deformation suppressing member 31 and the upper deformation suppressing member 32 is not particularly limited as long as the deformation of the vapor chamber 1 can be suppressed. For example, the lower deformation suppressing member 31 and the upper deformation suppressing member 32 are preferably formed of stainless steel such as SUS304 or SUS316L.

For example, the case where the lower metal sheet 10 is made of copper and the lower deformation suppressing member 31 is made of SUS304 will be described. The thermal expansion coefficient of copper at 0 ° C. to 100 ° C. is 16.6 × 10 ⁻⁶ / K, and the thermal expansion coefficient of SUS304 at 0 ° C. to 100 ° C. is 17.3 × 10 ⁻⁶ / K. For this reason, the thermal expansion coefficient of the lower deformation suppressing member 31 can be made larger than the thermal expansion coefficient of the lower metal sheet 10.

The case where the upper metal sheet 20 is formed of copper and the upper deformation suppressing member 32 is formed of SUS316L will be described. The thermal expansion coefficient of SUS316L at 0 ° C. to 100 ° C. is 16.0 × 10 ⁻⁶ / K. For this reason, the thermal expansion coefficient of the upper deformation suppressing member 32 can be made smaller than the thermal expansion coefficient of the upper metal sheet 20.

  When the lower deformation suppressing member 31 and the upper deformation suppressing member 32 are formed of stainless steel as described above, the lower metal sheet is formed by adhesive, brazing, soldering, diffusion bonding, laser welding, or the like. 10 and the upper metal sheet 20.

  The lower deformation suppressing member 31 and the upper deformation suppressing member 32 are not limited to being formed of stainless steel. For example, the lower deformation suppressing member 31 and the upper deformation suppressing member 32 may be formed of hard metal such as iron, nickel, cobalt, titanium, chromium, molybdenum, or an alloy thereof.

  Next, the operation of the present embodiment having such a configuration will be described. Here, although the manufacturing method of the vapor chamber 1 is demonstrated first using FIG. 9 thru | or FIG. 15, description of the half etching process of the upper side metal sheet 20 is simplified. 9 to 15 show a cross section similar to the cross section of FIG.

  First, as shown in FIG. 9, a flat lower metal sheet 10 is prepared. The lower metal sheet 10 prepared here has an outline shape as shown in FIG.

  Subsequently, as shown in FIG. 10, the lower metal sheet 10 is half-etched to form a lower flow path recess 12 constituting a part of the sealed space 3. In this case, first, a resist film (not shown) is formed on the upper surface 10a of the lower metal sheet 10 in a pattern corresponding to the plurality of lower flow path protrusions 13 and the lower peripheral wall 14 by photolithography. Subsequently, the upper surface 10a of the lower metal sheet 10 is half-etched as a half-etching process. As a result, the portion of the upper surface 10a of the lower metal sheet 10 corresponding to the opening (not shown) of the resist film is half-etched, so that the lower channel recess 12 and the lower channel as shown in FIG. A protrusion 13 and a lower peripheral wall 14 are formed. At this time, the lower injection channel recess 17 shown in FIGS. 1 and 5 is also formed at the same time. After the half etching process, the resist film is removed. Note that half-etching means etching for forming a recess that does not penetrate the material. For this reason, the depth of the recess formed by half etching is not limited to being half the thickness of the lower metal sheet 10. As the etchant, for example, an iron chloride-based etchant such as a ferric chloride aqueous solution or a copper chloride-based etchant such as a copper chloride aqueous solution can be used.

  On the other hand, in the same manner as the lower metal sheet 10, the upper metal sheet 20 is half-etched from the lower surface 20 a to form the upper channel recess 21, the upper channel protrusion 22, and the upper peripheral wall 23. In this way, the above-described upper metal sheet 20 is obtained.

  Next, as shown in FIG. 11, the wick W is inserted and fitted between the lower channel protrusions 13 of the lower channel recess 12.

  Next, as shown in FIG. 12, the lower metal sheet 10 having the lower flow path recess 12 and the upper metal sheet 20 having the upper flow path recess 21 are temporarily fixed. In this case, first, using the lower alignment hole 15 (see FIGS. 1 and 5) of the lower metal sheet 10 and the upper alignment hole 24 (see FIGS. 1 and 6) of the upper metal sheet 20, The metal sheet 10 and the upper metal sheet 20 are positioned. Subsequently, the lower metal sheet 10 and the upper metal sheet 20 are fixed. The fixing method is not particularly limited. For example, the lower metal sheet 10 and the upper metal sheet 20 are fixed by performing resistance welding on the lower metal sheet 10 and the upper metal sheet 20. May be. In this case, it is preferable to perform resistance welding in a spot manner using the electrode rod 40 as shown in FIG. Laser welding may be performed instead of resistance welding. Alternatively, the lower metal sheet 10 and the upper metal sheet 20 may be ultrasonically bonded and fixed by irradiating ultrasonic waves. Furthermore, although an adhesive may be used, it is preferable to use an adhesive that does not have an organic component or has few organic components. Thus, the lower metal sheet 10 and the upper metal sheet 20 are fixed in a positioned state.

  After temporary fixing, as shown in FIG. 13, the lower metal sheet 10 and the upper metal sheet 20 are permanently bonded by diffusion bonding. In diffusion bonding, the lower metal sheet 10 and the upper metal sheet 20 to be bonded are brought into close contact with each other, and the metal sheets 10 and 20 are pressurized in a controlled atmosphere such as in a vacuum or an inert gas. It is the method of joining together using the diffusion of the atom produced on a joining surface by heating together. In diffusion bonding, the materials of the lower metal sheet 10 and the upper metal sheet 20 are heated to a temperature close to the melting point. However, since the temperature is lower than the melting point, the metal sheets 10 and 20 can be prevented from melting and deforming. More specifically, the upper surface 14a of the lower peripheral wall 14 of the lower metal sheet 10 and the lower surface 23a of the upper peripheral wall 23 of the upper metal sheet 20 are diffusion bonded. Thus, the sealed space 3 is formed between the lower metal sheet 10 and the upper metal sheet 20 by the lower peripheral wall 14 and the upper peripheral wall 23. Further, the lower injection channel recess 17 (see FIGS. 1 and 5) and the upper injection channel recess 26 (see FIGS. 1 and 6) form an injection channel for the working fluid 2 communicating with the sealed space 3. Is done. Furthermore, the upper surface 13a of the lower flow path protrusion 13 of the lower metal sheet 10 and the lower surface 22a of the upper flow path protrusion 22 of the upper metal sheet 20 are diffusion-bonded as a bonding surface. Mechanical strength is improved.

  After the permanent bonding, as shown in FIG. 14, the lower deformation suppressing member 31 is bonded to the lower surface 10 b of the lower metal sheet 10, and the upper deformation suppressing member 32 is bonded to the upper surface 20 b of the upper metal sheet 20. Is done. In this case, for example, the lower metal sheet 10 and the lower deformation suppressing member 31, and the upper metal sheet 20 and the upper deformation suppressing member 32 are bonded by an adhesive, brazing, soldering, diffusion bonding, laser welding, or the like. May be. The lower deformation suppressing member 31 and the upper deformation suppressing member 32 may be formed on the lower surface 10b of the lower metal sheet 10 and the upper surface 20b of the upper metal sheet 20 by plating.

  Next, as shown in FIG. 15, the working fluid 2 is injected into the sealed space 3 from the injection portion 4 (see FIG. 1). At this time, first, the sealed space 3 is evacuated and decompressed, and then the working fluid 2 is injected into the sealed space 3. At the time of injection, the working fluid 2 passes through an injection channel formed by the lower injection channel recess 17 and the upper injection channel recess 26.

  After the injection of the working fluid 2, the above-described injection flow path is sealed. For example, it is preferable to irradiate the injection part 4 with a laser and partially melt the injection part 4 to seal the injection flow path. As a result, the communication between the sealed space 3 and the outside air is blocked, and the hydraulic fluid 2 is sealed in the sealed space 3. In this way, the hydraulic fluid 2 in the sealed space 3 is prevented from leaking outside.

  As described above, the vapor chamber 1 according to the present embodiment is obtained.

  The vapor chamber 1 obtained as described above is installed in a housing such as a mobile terminal, and is an object to be cooled on the lower surface 10b of the lower metal sheet 10 via the lower deformation suppressing member 31. A device D such as a CPU is attached. At this time, the bending strength of the lower deformation suppressing member 31 is larger than the bending strength of the lower metal sheet 10, and the bending strength of the upper deformation suppressing member 32 is larger than the bending strength of the upper metal sheet 20. Thereby, the lower metal sheet 10 and the upper metal sheet 20 are reinforced by the lower deformation suppressing member 31 and the upper deformation suppressing member 32, and the rigidity of the vapor chamber 1 is effectively enhanced. For this reason, when the vapor chamber 1 is installed in a housing such as a mobile terminal, deformation of the vapor chamber 1, particularly bending deformation is suppressed.

  Next, a method for operating the vapor chamber 1, that is, a method for cooling the device D will be described.

  When the lower metal sheet 10 is disposed vertically downward and the upper metal sheet 20 is disposed vertically upward, most of the hydraulic fluid 2 sealed in the sealed space 3 is affected by gravity, The metal sheet 10 stays in the lower channel recess 12.

  When the device D generates heat in this state, the hydraulic fluid 2 present in the evaporation unit 11 in the lower flow path recess 12 receives heat from the device D via the lower deformation suppressing member 31. The received heat is absorbed as latent heat, the working fluid 2 evaporates (vaporizes), and the vapor of the working fluid 2 is generated. Most of the generated steam rises in the sealed space 3 and diffuses into the upper flow path recess 21. A part of the generated steam diffuses in the lower channel recess 12 of the lower metal sheet 10. The steam in the upper flow path recess 21 and the lower flow path recess 12 is separated from the evaporation section 11, and most of the steam is transported to the peripheral portion having a relatively low temperature. The diffused vapor dissipates heat to the upper metal sheet 20 and is cooled. The heat received from the steam by the upper metal sheet 20 is transferred to the outside air through the housing member H (see FIGS. 2 and 3).

  The steam loses the latent heat absorbed in the evaporating section 11 by radiating heat to the upper metal sheet 20 and condenses. Most of the hydraulic fluid 2 that has become liquid descends in the upper flow path recess 21 and reaches the lower flow path recess 12. Since the working fluid 2 continues to evaporate in the evaporation section 11, the working fluid 2 in the portion other than the evaporation section 11 in the lower flow path recess 12 is transported toward the evaporation section 11. At this time, the lower flow path recess 12 is provided with a wick W that can exhibit a capillary action. For this reason, the hydraulic fluid 2 obtains a driving force toward the evaporation unit 11 by the capillary action of the wick W, and is smoothly transported toward the evaporation unit 11.

  The hydraulic fluid 2 that has reached the evaporator 11 receives heat from the device D again and evaporates. In this way, the hydraulic fluid 2 recirculates in the vapor chamber 1 while repeating phase change, that is, evaporation and condensation, and moves and releases the heat of the device D. As a result, the device D is cooled.

  By the way, when the vapor chamber 1 is operated, as described above, the working fluid 2 receives heat from the device D, and vapor of the working fluid 2 is generated. The generated steam is mainly diffused into the upper flow path recess 21. For this reason, the lower metal sheet 10, the upper metal sheet 20, the lower deformation suppressing member 31, and the upper deformation suppressing member 32 are thermally expanded. Further, as described above, the lower channel recess 12 of the lower metal sheet 10 mainly transports the liquid working fluid 2 having a relatively low temperature. Accordingly, the elongation due to the thermal expansion of the upper metal sheet 20 can be larger than the elongation due to the thermal expansion of the lower metal sheet 10. For this reason, warpage may occur in the vapor chamber 1 due to the difference between the elongation due to the thermal expansion of the lower metal sheet 10 and the elongation due to the thermal expansion of the upper metal sheet 20.

  However, in the present embodiment, the lower deformation suppressing member 31 having a bending strength larger than that of the lower metal sheet 10 is provided on the lower surface 10 b of the lower metal sheet 10. Further, an upper deformation suppressing member 32 having a bending strength larger than that of the upper metal sheet 20 is provided on the upper surface 20 b of the upper metal sheet 20. Thus, the lower metal sheet 10 and the upper metal sheet 20 are reinforced by the lower deformation suppressing member 31 and the upper deformation suppressing member 32. For this reason, the rigidity of the vapor chamber 1 is ensured and deformation of the vapor chamber 1 is suppressed.

  In the present embodiment, the thermal expansion coefficient of the lower deformation suppressing member 31 is larger than the thermal expansion coefficient of the lower metal sheet 10. Accordingly, the elongation due to the thermal expansion of the lower deformation suppressing member 31 is larger than the elongation due to the thermal expansion of the lower metal sheet 10. For this reason, the elongation of the lower metal sheet 10 is increased by the lower deformation suppressing member 31. Further, the thermal expansion coefficient of the upper deformation suppressing member 32 is smaller than the thermal expansion coefficient of the upper metal sheet 20. Thereby, the elongation due to the thermal expansion of the upper deformation suppressing member 32 is smaller than the elongation due to the thermal expansion of the upper metal sheet 20. For this reason, the upper deformation suppressing member 32 reduces the elongation of the upper metal sheet 20 due to thermal expansion. As a result, the difference between the elongation due to the thermal expansion of the lower metal sheet 10 and the elongation due to the thermal expansion of the upper metal sheet 20 is reduced. For this reason, the deformation | transformation by the curvature of the vapor chamber 1 resulting from the difference of the elongation by the thermal expansion of the lower metal sheet 10 and the expansion by the thermal expansion of the upper metal sheet 20 is suppressed.

  Thus, according to the present embodiment, the lower deformation suppression member 31 is provided on the lower surface 10 b of the lower metal sheet 10, and the upper deformation suppression member 32 is provided on the upper surface 20 b of the upper metal sheet 20. Thereby, deformation of the vapor chamber 1 can be suppressed. For this reason, it is possible to prevent the flow area of the lower flow path recess 12 and the upper flow path recess 21 constituting the sealed space 3 from being reduced due to the deformation of the vapor chamber 1, and to ensure stable operation of the vapor chamber 1. can do.

  Further, according to the present embodiment, the lower deformation suppressing member 31 having a bending strength larger than that of the lower metal sheet 10 is provided on the lower surface 10 b of the lower metal sheet 10, and the bending strength larger than that of the upper metal sheet 20. The upper deformation suppressing member 32 having the above is provided on the upper surface 20 b of the upper metal sheet 20. Accordingly, the lower metal sheet 10 and the upper metal sheet 20 can be reinforced by the lower deformation suppressing member 31 and the upper deformation suppressing member 32. For this reason, the rigidity of the vapor chamber 1 can be effectively increased, and deformation of the vapor chamber 1 can be suppressed. In this case, since the deformation of the vapor chamber 1 when the vapor chamber 1 is installed in a mobile terminal or the like can be suppressed, the handling of the vapor chamber 1 can be facilitated. Further, the deformation of the vapor chamber 1 when the sealed space 3 is evacuated can be suppressed. Furthermore, deformation due to thermal expansion that occurs when other components or the like are joined to the vapor chamber 1 by soldering can be suppressed.

  Moreover, according to this Embodiment, the thermal expansion coefficient of the lower side deformation | transformation suppression member 31 is larger than the thermal expansion coefficient of the lower side metal sheet 10, and the thermal expansion coefficient of the upper side deformation | transformation suppression member 32 is the upper side metal sheet 20. The coefficient of thermal expansion is smaller. Accordingly, the elongation due to the thermal expansion of the lower deformation suppressing member 31 can be made larger than the elongation due to the thermal expansion of the lower metal sheet 10, and the elongation due to the thermal expansion of the upper deformation suppressing member 32 can be increased. The elongation by thermal expansion of 20 can be made smaller. For this reason, the lower deformation suppression member 31 can increase the elongation of the lower metal sheet 10, and the upper deformation suppression member 32 can reduce the elongation of the upper metal sheet 20. As a result, the difference between the elongation due to the thermal expansion of the lower deformation suppressing member 31 and the elongation due to the thermal expansion of the upper deformation suppressing member 32 can be reduced. For this reason, the deformation | transformation by the curvature of the vapor chamber 1 resulting from the difference of the elongation by the thermal expansion of the lower metal sheet 10 and the expansion by the thermal expansion of the upper metal sheet 20 can be suppressed.

  In the present embodiment described above, an example in which the deformation suppressing members 31 and 32 that suppress the deformation of the vapor chamber 1 are provided on the lower surface 10b of the lower metal sheet 10 and the upper surface 20b of the upper metal sheet 20 is provided. explained. However, the present invention is not limited to this. For example, the deformation suppressing members 31 and 32 may not be provided on one of the lower surface 10b of the lower metal sheet 10 and the upper surface 20b of the upper metal sheet 20. Even in this case, the deformation of the vapor chamber 1 can be suppressed by the lower deformation suppressing member 31 or the upper deformation suppressing member 32. In the case where the lower deformation suppressing member 31 is not provided, the device D (see FIGS. 1 to 3 and FIG. 5) has the lower metal sheet 10 when the vapor chamber 1 is installed in a housing such as a mobile terminal. It is attached to the lower surface 10b. Further, when the upper deformation suppressing member 32 is not provided, the housing member H (see FIGS. 2 and 3) is disposed on the upper surface 20b of the upper metal sheet 20 when the vapor chamber 1 is installed in a housing such as a mobile terminal. Be placed.

  In the above-described embodiment, the bending strength of the lower deformation suppressing member 31 is greater than the bending strength of the lower metal sheet 10, and the bending strength of the upper deformation suppressing member 32 is the bending strength of the upper metal sheet 20. The example which has become larger than intensity | strength was demonstrated. However, the present invention is not limited to this. For example, even if the bending strength of the lower deformation suppressing member 31 is not greater than the bending strength of the lower metal sheet 10, the thermal expansion coefficient of the lower deformation suppressing member 31 is the thermal expansion of the lower metal sheet 10. It only needs to be larger than the coefficient. Even if the bending strength of the upper deformation suppressing member 32 is not greater than the bending strength of the upper metal sheet 20, the thermal expansion coefficient of the upper deformation suppressing member 32 is smaller than the thermal expansion coefficient of the upper metal sheet 20. It only has to be. In this case, as described above, the difference between the elongation due to the thermal expansion of the lower deformation suppressing member 31 and the elongation due to the thermal expansion of the upper deformation suppressing member 32 can be reduced. For this reason, the deformation | transformation by the curvature of the vapor chamber 1 resulting from the difference of the elongation by the thermal expansion of the lower metal sheet 10 and the expansion by the thermal expansion of the upper metal sheet 20 can be suppressed.

  Further, in the present embodiment described above, the plurality of lower flow path protrusions 13 are disposed along the longitudinal direction of the vapor chamber 1 and are also disposed along the transverse direction of the vapor chamber 1. An example was described. However, the present invention is not limited to this, and the arrangement of the plurality of lower flow path protrusions 13 is arbitrary as long as the mechanical strength of the vapor chamber 1 can be secured by contacting the upper flow path protrusion 22. is there.

  Moreover, in this Embodiment mentioned above, while the lower channel protrusion part of the lower metal sheet 10 is formed as a boss | hub, the upper channel protrusion part of the upper metal sheet 20 is formed as a boss | hub. explained. However, the present invention is not limited to this. That is, the vapor generated in the evaporation unit 11 can be diffused into the sealed space 3, the working fluid 2 condensed from the vapor is transported to the evaporation unit 11, and the lower channel protrusion and the upper channel are further transported. The shape of the lower channel projection and the upper channel projection is arbitrary as long as the projection can be brought into contact with the projection.

  More specifically, at least one of the upper flow path protrusion and the lower flow path protrusion may be formed as a wall (not shown) extending in a substantially elongated shape along a predetermined direction. This wall may extend along the longitudinal direction of the vapor chamber 1 or may extend along the radial direction from the evaporation unit 11 in a plan view. Even in this case, it is preferable that the lower flow path protrusion and the upper flow path protrusion are arranged so as to overlap in a plan view.

  Further, the upper metal sheet 20 is formed in a flat plate shape and does not have to have the upper flow path recess 21. In this case, the vapor of the working fluid 2 evaporated in the evaporation unit 11 diffuses in the lower flow path recess 12 of the lower metal sheet 10, dissipates heat to the upper metal sheet 20, and is cooled and condensed. That is, the entire sealed space 3 is constituted by the lower flow path recess 12. Further, when the upper metal sheet 20 is formed in a flat plate shape, the mechanical strength of the vapor chamber 1 can be improved.

  Further, in the present embodiment described above, after the lower metal sheet 10 and the upper metal sheet 20 are diffusion bonded as permanent bonding, the lower deformation suppressing member 31 is attached to the lower surface 10b of the lower metal sheet 10. The example in which the upper deformation suppressing member 32 is bonded to the upper surface 20b of the upper metal sheet 20 has been described. However, the present invention is not limited to this. For example, as shown in FIG. 16, the deformation suppressing members 31 and 32 are made of the corresponding metal before the lower metal sheet 10 and the upper metal sheet 20 are diffusion bonded. You may make it join to the sheet | seats 10 and 20. FIG. In this case, the lower metal sheet 10 to which the lower deformation suppressing member 31 is bonded and the upper metal sheet 20 to which the upper deformation suppressing member 32 is bonded are permanently bonded by diffusion bonding. The lower metal sheet 10 (vapor chamber metal sheet) to which the lower deformation suppressing member 31 is joined corresponds to the vapor chamber metal sheet assembly 110. Similarly, the upper metal sheet 20 (vapor chamber metal sheet) to which the upper deformation suppressing member 32 is joined also corresponds to the vapor chamber metal sheet assembly 120. In this case, the deformation suppressing members 31 and 32 are configured by a plating layer 33 deposited on the upper metal sheet 20 or the lower metal sheet 10 by plating, and the plating layer 33 is bonded to the metal sheets 10 and 20. It is preferable that Examples of the plating layer 33 include hard plating layers such as nickel plating, nickel cobalt alloy plating, hard chrome plating, and nickel phosphorus plating. However, also in the modification shown in FIG. 16, the deformation suppressing members 31 and 32 are formed separately from the metal sheets 10 and 20 by the material as in the above-described embodiment, and the metal sheets 10 and 20 are formed. You may make it join.

  The present invention is not limited to the above-described embodiments and modifications as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments and modifications. You may delete a some component from all the components shown by embodiment and a modification.

DESCRIPTION OF SYMBOLS 1 Vapor chamber 2 Hydraulic fluid 3 Sealing space 10 Lower metal sheet 10b Lower surface 11 Evaporating part 12 Lower flow path recessed part 20 Upper metal sheet 20b Upper surface 21 Upper flow path recessed part 31 Lower deformation suppressing member 32 Upper deformation suppressing member 110, 120 Metal sheet assembly D device for vapor chamber

Claims (13)

A vapor chamber that has a sealed space in which a working fluid is sealed, and cools a device to be cooled;
A lower metal sheet to which the cooled device is attached;
An upper metal sheet provided on the lower metal sheet and forming the sealed space with the lower metal sheet;
A vapor chamber comprising: a deformation suppressing member that is provided on at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet and suppresses deformation of the vapor chamber. The deformation suppressing member is provided on the lower surface of the lower metal sheet,
The vapor chamber according to claim 1, wherein a bending strength of the deformation suppressing member provided on the lower surface of the lower metal sheet is greater than a bending strength of the lower metal sheet. The deformation suppressing member is provided on the lower surface of the lower metal sheet,
The vapor chamber according to claim 1, wherein a thermal expansion coefficient of the deformation suppressing member provided on the lower surface of the lower metal sheet is larger than a thermal expansion coefficient of the lower metal sheet. The deformation suppressing member is provided on the upper surface of the upper metal sheet,
The vapor chamber according to any one of claims 1 to 3, wherein a bending strength of the deformation suppressing member provided on the upper surface of the upper metal sheet is larger than a bending strength of the upper metal sheet. The deformation suppressing member is provided on the upper surface of the upper metal sheet,
The vapor chamber according to any one of claims 1 to 4, wherein a thermal expansion coefficient of the deformation suppressing member provided on the upper surface of the upper metal sheet is smaller than a thermal expansion coefficient of the upper metal sheet.   The vapor chamber according to claim 1, wherein the deformation suppressing member is made of stainless steel.   The vapor chamber according to any one of claims 1 to 6, wherein the deformation suppressing member includes a plating layer.   The vapor chamber according to any one of claims 1 to 7, wherein the lower metal sheet and the upper metal sheet are made of copper or a copper alloy. A metal sheet assembly for a vapor chamber for a vapor chamber that has a sealed space in which a working fluid is sealed and cools a device to be cooled,
A metal sheet for the vapor chamber;
A metal sheet assembly for a vapor chamber, comprising: a deformation suppressing member that is provided on one surface of the metal sheet for the vapor chamber and suppresses deformation of the vapor chamber. A method for manufacturing a vapor chamber, which is formed between a lower metal sheet and an upper metal sheet, has a sealed space in which a working fluid is enclosed, and cools a device to be cooled,
Preparing the lower metal sheet to which the cooled device is attached and the upper metal sheet;
Joining the lower metal sheet and the upper metal sheet, and forming the sealed space between the lower metal sheet and the upper metal sheet;
After joining the lower metal sheet and the upper metal sheet, a deformation suppressing member that suppresses deformation of the vapor chamber is provided on at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet. Process,
And a step of enclosing the hydraulic fluid in the sealed space. A method for manufacturing a vapor chamber, which is formed between a lower metal sheet and an upper metal sheet, has a sealed space in which a working fluid is enclosed, and cools a device to be cooled,
Preparing the lower metal sheet to which the cooled device is attached and the upper metal sheet;
Providing a deformation suppressing member for suppressing deformation of the vapor chamber on at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet;
Joining the lower metal sheet and the upper metal sheet provided with the deformation suppressing member on at least one, and forming the sealed space between the lower metal sheet and the upper metal sheet;
And a step of enclosing the hydraulic fluid in the sealed space.   In the step of providing the deformation suppressing member, the deformation suppressing member is bonded to at least one of the lower surface of the lower metal sheet and the upper surface of the upper metal sheet by adhesive, brazing, soldering, diffusion bonding, laser welding. The method of manufacturing a vapor chamber according to claim 10 or 11, wherein the vapor chamber is joined by any one of the above.   The step of providing the deformation suppressing member, wherein the deformation suppressing member is formed on at least one of a lower surface of the lower metal sheet and an upper surface of the upper metal sheet by plating. A method for manufacturing a vapor chamber.

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