JP2024024081A - Metal sheet for vapor chamber, electronic equipment and vapor chamber - Google Patents

Abstract

An object of the present invention is to provide a vapor chamber and a metal sheet for a vapor chamber, which allow degassing of the vapor chamber and injection of a working fluid into the vapor chamber in a short time when manufacturing the vapor chamber.
A vapor chamber includes a first metal sheet and a second metal sheet provided on the first metal sheet. At least one of the first metal sheet and the second metal sheet is formed with a plurality of vapor flow path recesses through which the vapor of the working fluid passes, and at least one of the first metal sheet and the second metal sheet is formed with a plurality of vapor flow path recesses through which the vapor of the working fluid passes. A liquid flow path is formed through which the liquid flows. An injection channel recess for injecting a liquid working fluid is formed in at least one of the first metal sheet and the second metal sheet, and the width of the injection channel recess is wider than the width of the lower steam passage of the steam channel recess. It is also wider.
[Selection diagram] Figure 4

Description

The present invention relates to a vapor chamber, an electronic device, and a metal sheet for a vapor chamber.

BACKGROUND ART Devices that generate heat, such as central processing units (CPUs) used in mobile terminals such as mobile terminals and tablet terminals, are cooled by heat dissipation members such as heat pipes (see, for example, Patent Document 1). In recent years, as mobile terminals and the like have become thinner, there has been a demand for thinner heat dissipation members, and progress is being made in developing vapor chambers that can be made thinner than heat pipes. A working fluid is sealed in the vapor chamber, and this working fluid cools the device by absorbing heat from the device and releasing it to the outside.

More specifically, the working fluid in the vapor chamber receives heat from the device in a portion close to the device (evaporation section) and evaporates into vapor, and then the vapor moves to a position away from the evaporation section. It is cooled and condensed into a liquid. A capillary structure (wick) as a liquid flow path is provided inside the vapor chamber, and the liquefied working fluid passes through this liquid flow path, is transported to the evaporation section, and is evaporated again in the evaporation section. Evaporates due to heat. In this way, the working fluid circulates in the vapor chamber while undergoing phase changes, that is, repeating evaporation and condensation, thereby transferring heat from the device and increasing heat dissipation efficiency.

Unexamined Japanese Patent Publication No. 2016-50682

By the way, in a flat heat exchanger such as a vapor chamber, a metal sheet is provided with an injection path for injecting a working fluid after degassing. However, if the width of the injection path is made narrower than the steam passage or the groove of the wick, as in the case of the sheet-type heat pipe described in Patent Document 1, for example, degassing inside the vapor chamber or activation inside the vapor chamber may occur. There is a problem in that the work of injecting the liquid takes time and workability decreases.

The present invention has been made in consideration of these points, and it is possible to perform degassing work in the vapor chamber and work to inject working fluid into the vapor chamber in a short time when manufacturing the vapor chamber. The present invention aims to provide vapor chambers, electronic devices, and metal sheets for vapor chambers.

The present invention
A vapor chamber filled with hydraulic fluid,
a first metal sheet;
a second metal sheet laminated on the first metal sheet,
A steam passage recess including a plurality of steam passages through which the vapor of the working fluid passes is formed in at least one of the first metal sheet and the second metal sheet, and
A liquid flow path portion through which the liquid working fluid passes is formed in at least one of the first metal sheet and the second metal sheet,
An injection channel recess for injecting the liquid working fluid is formed in at least one of the first metal sheet and the second metal sheet,
a vapor chamber, wherein the width of the injection channel recess is wider than the width of the vapor passage;
I will provide a.

In addition, in the vapor chamber mentioned above,
a plurality of struts protruding from the injection channel recess;
You can do it like this.

Moreover, in the vapor chamber mentioned above,
A caulking region is formed in the injection channel recess, and the caulking region has a plurality of protrusions.
You can do it like this.

Moreover, in the vapor chamber mentioned above,
The width of the injection channel recess is 1.5 times or more the width of the steam passage,
You can do it like this.

Moreover, in the vapor chamber mentioned above,
The depth of the injection channel recess is deeper than the depth of the steam passage.
You can do it like this.

Moreover, in the vapor chamber mentioned above,
The liquid flow path portion has a plurality of main flow grooves extending parallel to each other and a communication groove connecting the main flow grooves that are adjacent to each other.
You can do it like this.

Moreover, in the vapor chamber mentioned above,
A convex portion is formed so as to be surrounded by the main flow groove and the communication groove, and the plurality of convex portions are arranged in a staggered manner in a plan view.
You can do it like this.

Moreover, in the vapor chamber mentioned above,
the second metal sheet is provided on the first metal sheet,
You can do it like this.

Moreover, in the vapor chamber mentioned above,
further comprising a third metal sheet interposed between the first metal sheet and the second metal sheet,
The vapor flow path recess is formed in one of the first metal sheet and the second metal sheet, and the liquid flow path is formed in the other,
The third metal sheet is provided with a communication portion that communicates the vapor flow path recess and the liquid flow path.
You can do it like this.

Moreover, the present invention
A vapor chamber filled with hydraulic fluid,
a first metal sheet;
a second metal sheet laminated on the first metal sheet;
a third metal sheet interposed between the first metal sheet and the second metal sheet;
The third metal sheet includes a first surface provided on the first metal sheet side and a second surface provided on the second metal sheet side,
A steam passage portion including a plurality of steam passages through which the vapor of the working fluid passes is formed on at least one of the first surface and the second surface of the third metal sheet,
A liquid flow path portion through which the liquid working fluid passes is formed on at least one of the first surface and the second surface of the third metal sheet,
An injection channel portion for injecting the liquid working fluid is formed on at least one of the first surface and the second surface of the third metal sheet,
The width of the injection channel portion is wider than the width of the vapor passage.
I will provide a.

Moreover, the present invention
housing and
a device contained within the housing;
an electronic device comprising a vapor chamber as described above in thermal contact with the device;
I will provide a.

Moreover, the present invention
A vapor chamber metal sheet for a vapor chamber in which a working fluid is sealed,
The first page and
a second surface provided on the opposite side to the first surface,
A vapor flow path recess including a plurality of vapor paths through which vapor of the working fluid passes is formed on the first surface,
a metal sheet for a vapor chamber, wherein an injection channel recess for injecting the liquid working fluid is formed on the first surface, and the width of the injection channel recess is wider than the width of the vapor passage;
I will provide a.

According to the present invention, when manufacturing a vapor chamber, it is possible to perform the work of degassing the vapor chamber and the work of injecting the working fluid into the vapor chamber in a short time.

FIG. 1 is a schematic perspective view illustrating an electronic device according to a first embodiment of the present invention. FIG. 2 is a top view showing the vapor chamber according to the first embodiment of the invention. FIG. 3 is a cross-sectional view taken along line AA, showing the vapor chamber of FIG. 2. 4 is a top view of the lower metal sheet of the vapor chamber of FIG. 2; FIG. 5 is a bottom view of the upper metal sheet of the vapor chamber of FIG. 2; FIG. 6 is an enlarged top view of the lower injection protrusion of the lower metal sheet of FIG. 4; FIG. FIG. 7 is a cross-sectional view taken along line BB showing the lower injection protrusion of the lower metal sheet of FIG. FIG. 8 is an enlarged top view showing the liquid flow path section of FIG. 4. FIG. FIG. 9 is a cross-sectional view taken along the line CC in FIG. 8 with an upper metal sheet added thereto. FIG. 10 is an enlarged top view showing a modification of the liquid flow path section in FIG. 8. FIG. FIGS. 11(a) to 11(c) are diagrams showing the method (first half) of manufacturing a vapor chamber according to the first embodiment of the present invention. FIGS. 12(a) to 12(c) are diagrams showing a method (second half) of manufacturing a vapor chamber according to the first embodiment of the present invention. FIG. 13 is a diagram showing a modified example (modified example 1) of the vapor chamber of FIG. 3. FIG. 14 is a diagram showing another modification (modification 2) of the vapor chamber in FIG. 3. FIG. 15 is a diagram showing another modification (modification 3) of the lower injection protrusion in FIG. FIG. 16 is a diagram showing another modification (modification 4) of the lower injection protrusion in FIG. FIG. 17 is a sectional view showing a vapor chamber in a second embodiment of the invention. FIG. 18 is a bottom view of the upper metal sheet of FIG. 17. FIG. 19 is a top view of the intermediate metal sheet of FIG. 17. FIG. 20 is a sectional view showing a vapor chamber in a third embodiment of the present invention. FIG. 21 is a top view of the intermediate metal sheet of FIG. 20. FIG. 22 is a sectional view showing a vapor chamber in the fourth embodiment of the present invention. FIG. 23 is a bottom view of the intermediate metal sheet of FIG. 22. FIG. 24 is a top view of the intermediate metal sheet of FIG. 22. FIG. 25 is a sectional view showing a modification of the vapor chamber of FIG. 22.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In addition, in the drawings attached to this specification, for convenience of illustration and ease of understanding, the scale, vertical and horizontal dimension ratios, etc. are appropriately changed and exaggerated from those of the actual drawings.

In addition, terms such as "parallel", "orthogonal", "identical", etc., lengths, angles, and physical properties used in this specification specify shapes, geometric conditions, physical properties, and their degree. The values of , etc. shall not be bound by strict meanings, but shall be interpreted to include the range to which similar functions can be expected. Furthermore, in the drawings, for clarity, the shapes of multiple parts that can be expected to have similar functions are shown in a regular manner, but without being bound by a strict meaning, it is possible to expect the functions The shapes of the portions may be different from each other as long as the shapes can be different from each other. In addition, in the drawings, boundaries indicating bonding surfaces between members are shown as simple straight lines for convenience, but they are not restricted to exact straight lines and can be used to achieve the desired bonding performance. The shape of the boundary line is arbitrary within the range possible.

(First embodiment)
A vapor chamber, an electronic device, and a vapor chamber metal sheet according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 16. The vapor chamber 1 in this embodiment is a device installed in the electronic device E in order to cool a device D as a heating element housed in the electronic device E. Examples of device D include electronic devices that generate heat (cooled devices) such as central processing units (CPUs), light emitting diodes (LEDs), and power semiconductors used in mobile terminals such as mobile terminals and tablet terminals. It will be done.

Here, first, an electronic device E in which a vapor chamber 1 according to the present embodiment is mounted will be described using a tablet terminal as an example. As shown in FIG. 1, the electronic device E (tablet terminal) includes a housing H, a device D housed in the housing H, and a vapor chamber 1. In the electronic device E shown in FIG. 1, a touch panel display TD is provided on the front surface of the housing H. A vapor chamber 1 is housed within a housing H and placed in thermal contact with a device D. This allows the vapor chamber 1 to receive heat generated by 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 fluid 2, which will be described later. In this way, 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.

Next, the vapor chamber 1 in this embodiment will be explained. The vapor chamber 1 has a sealed space 3 in which a working fluid 2 is sealed, and the working fluid 2 in the sealed space 3 undergoes repeated phase changes to effectively cool the device D of the electronic equipment E described above. It is supposed to be done.

The vapor chamber 1 is generally formed into a thin flat plate shape. Although the planar shape of the vapor chamber 1 is arbitrary, it may be rectangular as shown in FIG. In this case, the vapor chamber 1 has four straight outer edges 1a, 1b forming an out-of-plane contour. Two of the outer edges 1a are formed along a first direction X, which will be described later, and the remaining two outer edges 1b are formed along a second direction Y, which will be described later. The planar shape of the vapor chamber 1 may be, for example, a rectangle with one side of 1 cm and the other side of 3 cm, or a square with one side of 15 cm, and the planar dimensions of the vapor chamber 1 are arbitrary. . Further, the planar shape of the vapor chamber 1 is not limited to a rectangular shape, and can be any shape such as a circular shape, an elliptical shape, an L-shape, a T-shape, or the like.

As shown in FIGS. 2 and 3, the vapor chamber 1 includes a lower metal sheet 10 (first metal sheet or second metal sheet, vapor chamber metal sheet) and an upper metal sheet laminated on the lower metal sheet 10. Sheet 20 (second metal sheet or first metal sheet, vapor chamber metal sheet). In this embodiment, the upper metal sheet 20 is provided on the lower metal sheet 10. The lower metal sheet 10 has an upper surface 10a (first surface) and a lower surface 10b (second surface) provided on the opposite side to the upper surface 10a. The upper metal sheet 20 has a lower surface 20a (a surface on the side of the lower metal sheet 10) superimposed on the upper surface 10a (a surface on the side of the upper metal sheet 20) of the lower metal sheet 10, and a side opposite to the lower surface 20a. The upper surface 20b is provided. A device D, which is an object to be cooled, is attached to the lower surface 10b of the lower metal sheet 10 (in particular, the lower surface of the evaporator 11, which will be described later).

A sealed space 3 in which a working fluid 2 is sealed is formed between the lower metal sheet 10 and the upper metal sheet 20. In the present embodiment, the sealed space 3 mainly includes a steam flow path section 80 (a lower steam flow path recess 12 and an upper steam flow path recess 21 to be described later) through which the vapor of the working fluid 2 passes, and a steam flow path section 80 through which the vapor of the working fluid 2 mainly passes. It has a liquid flow path section 30 through which the liquid flow path section 30 passes. 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 joined by diffusion bonding, which will be described later. In the embodiments shown in FIGS. 2 and 3, the lower metal sheet 10 and the upper metal sheet 20 except for the injection portion 4 described later are both formed into a rectangular shape in plan view, but the present invention is not limited to this. Never. Here, the plane view refers to a direction perpendicular to the surface of the vapor chamber 1 that receives heat from the device D (the lower surface 10b of the lower metal sheet 10) and the surface that releases the received heat (the upper surface 20b of the upper metal sheet 20). This corresponds to, for example, a state in which the vapor chamber 1 is seen from above (see FIG. 2) or a state in which it is seen from below.

Note that when the vapor chamber 1 is installed in a mobile terminal, the vertical relationship between the lower metal sheet 10 and the upper metal sheet 20 may be disrupted depending on the posture of the mobile terminal.
However, in this embodiment, for convenience, the metal sheet that receives heat from device D is referred to as the lower metal sheet 10, the metal sheet that releases the received heat is referred to as the upper metal sheet 20, and the lower metal sheet 10 is referred to as the lower metal sheet 10. The explanation will be made with the upper metal sheet 20 disposed on the lower side and the upper metal sheet 20 on the upper side.

As shown in FIG. 2, the vapor chamber 1 further includes, at one of the pair of ends in the first direction X, an injection part 4 for injecting the working fluid 2 into the sealed space 3. This injection part 4 includes a lower injection protrusion 16 that projects laterally from the end surface of the lower metal sheet 10 (the surface corresponding to the outer edge 1b in FIG. 2), and an end surface of the upper metal sheet 20 (the surface corresponding to the outer edge 1b in FIG. 2). and an upper injection protrusion 25 that protrudes laterally from the surface corresponding to the upper injection protrusion 25 . A lower injection channel recess 17 (injection channel recess) is formed on the upper surface of the lower injection protrusion 16 (a surface corresponding to the upper surface 10a of the lower metal sheet 10) (see FIG. 4). On the other hand, no recess is formed on the lower surface of the upper injection protrusion 25 (the surface corresponding to the lower surface 20a of the upper metal sheet 20), and the upper injection protrusion 25 has a lower surface (a surface corresponding to the lower surface 20a of the upper metal sheet 20). It has the same thickness as the material sheet M) (see FIG. 5). The inner end of the lower injection channel recess 17 (the end on the sealed space 3 side) communicates with the lower vapor flow channel recess 12, and the outer end of the lower injection channel recess 17 (the end on the opposite side of the sealed space 3) communicates with the lower vapor flow channel recess 12. The side end) is open outward. The lower injection channel recess 17 and the upper injection protrusion 25 together 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 then passes through the injection channel and is injected into the sealed space 3. In addition, in this embodiment, an example is shown in which the injection part 4 is provided at one end of the pair of ends in the first direction X of the vapor chamber 1, but the present invention is not limited to this. It can be installed at any position. Moreover, two or more injection parts 4 may be provided.

Next, the configuration of the lower metal sheet 10 will be explained. As shown in FIG. 4, the lower metal sheet 10 includes an evaporation section 11 in which the working fluid 2 evaporates to generate steam, and a lower steam flow path provided on the upper surface 10a and formed in a rectangular shape in plan view. It has a recessed part 12 (first steam flow path part).
Among these, the lower vapor flow path concave portion 12 constitutes a part of the above-mentioned sealed space 3, and is configured mainly through which the vapor generated in the evaporation section 11 passes.

The evaporator 11 is arranged within the lower vapor flow path recess 12, and the vapor in the lower vapor flow path recess 12 is diffused in the direction away from the evaporator 11, and most of the vapor is relatively small. It is transported towards the cooler periphery. The evaporation section 11 is a section where the working fluid 2 in the sealed space 3 evaporates by receiving heat from the device D attached to the lower surface 10b of the lower metal sheet 10. For this reason, the term evaporation section 11 is not limited to a portion that overlaps the device D, but is used as a concept that includes a portion where the working fluid 2 can be evaporated even if it does not overlap the device D. Here, the evaporator 11 can be provided at any location on the lower metal sheet 10, but in FIGS. 2 and 4, an example is shown in which it is provided in the center of the lower metal sheet 10. . In this case, the operation of the vapor chamber 1 can be stabilized regardless of the posture of the mobile terminal on which the vapor chamber 1 is installed.

In this embodiment, as shown in FIG. 3 and FIG. A plurality of lower channel wall portions 13 (first channel protruding portions) are provided that protrude in a direction perpendicular to . In this case, the lower channel wall portion 13 protrudes in a direction perpendicular to the bottom surface 12a, but is not limited thereto, and may protrude in a direction other than perpendicular to the bottom surface 12a. In this embodiment, an example is shown in which the lower flow path wall portion 13 extends in an elongated shape along the first direction X (longitudinal direction, left-right direction in FIG. 4) of the vapor chamber 1. The lower flow path wall portion 13 includes an upper surface 13a (a contact surface, a protruding end surface) that abuts a lower surface 22a of the upper flow path wall portion 22, which will be described later. This upper surface 13a is a surface that will not be etched in the etching process described later, and is formed on the same plane as the upper surface 10a of the lower metal sheet 10. Further, the lower flow path wall portions 13 are arranged parallel to each other and spaced apart from each other at equal intervals.

As shown in FIGS. 3 and 4, the lower steam passage recess 12 includes a plurality of lower steam passages 81 (first steam passages) partitioned by the lower passage wall 13. The lower steam passages 81 extend in an elongated shape along the first direction X and are arranged parallel to each other. Both ends of each lower steam passage 81 communicate with a lower communication steam passage 82 that extends in an elongated shape along the second direction Y, and each lower steam passage 81 communicates with a lower communication steam passage 82 via the lower communication steam passage 82. are communicating. In this way, the steam of the working fluid 2 flows around each of the lower flow passage walls 13 (the lower steam passage 81 and the lower communication steam passage 82) and reaches the peripheral edge of the lower steam passage recess 12. The structure is such that steam is transported towards the vessel, and the flow of steam is prevented from being obstructed. In addition, in FIG. 3, the cross-sectional shape (cross-section in the second direction Y) of the lower steam passage 81 of the lower steam passage recess 12 is rectangular. However, the present invention is not limited to this, and the cross-sectional shape of the lower steam passage 81 may be, for example, curved, semicircular, or V-shaped, so that the vapor of the working fluid 2 can be diffused. Optional if possible. The same applies to the lower communication steam passage 82. The width (dimension in the second direction Y) w7 of the lower steam passage 81 corresponds to the interval between the lower flow passage wall portions 13, which will be described later.
The same applies to the width (dimension in the first direction X) of the lower communication steam passage 82.

The lower channel wall portion 13 is arranged so as to overlap a corresponding upper channel wall portion 22 (described later) of the upper metal sheet 20 in a plan view, and is intended to improve the mechanical strength of the vapor chamber 1. . The lower steam passage 81 is formed to overlap a corresponding upper steam passage 83 (described later) in plan view. Similarly, the lower communicating steam passage 82 is formed to overlap a corresponding upper communicating steam passage 84 (described later) in plan view.

The width w0 of the lower steam passage wall 13 is, for example, 0.05 mm to 30 mm, preferably 0.05 mm to 2.0 mm, and the width w7 of the lower steam passage 81 of the lower steam passage recess 12 (i.e. The distance between adjacent lower channel wall portions 13 is 0.05 mm to 30 mm, preferably 0.05 mm to 2.0 mm. Here, the widths w0 and w7 are the dimensions of the lower flow path wall portion 13 and the lower steam flow path recess 12 in the second direction Y of the lower flow path wall portion 13, and are the dimensions of the upper surface of the lower metal sheet 10. 10a, and correspond to, for example, the vertical dimension in FIG. 4. Further, the height of the lower flow path wall portion 13 (in other words, the maximum depth of the lower steam flow path recess 12) h0 (see FIG. 3) is at least 10 μm smaller than the thickness T1 of the lower metal sheet 10. It is preferable. When the remainder obtained by subtracting h0 from T1 is set to 10 μm or more, it is possible to prevent the lower steam flow path recessed portion 12 from being damaged due to insufficient strength. The thickness of the vapor chamber 1 may be between 0.1 mm and 2.0 mm, and the thickness T1 of the lower metal sheet 10 and the thickness T2 of the upper metal sheet 20 may be equal. For example, when the thickness of the vapor chamber 1 is 0.5 mm and T1 and T2 are the same, h0 is preferably 200 μm.

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

The lower injection protrusion 16 of the injection part 4 described above is used to evacuate the sealed space 3 or inject the liquid working fluid 2 toward the sealed space 3 during manufacturing of the vapor chamber 1. It will be done. The lower injection protrusion 16 is formed to protrude outward from the end surface of the lower metal sheet 10 in plan view. Note that the lower injection protrusion 16 is formed at a position offset from the center of the lower metal sheet 10 in the width direction (second direction Y), but the present invention is not limited to this. It may be formed at the center in the direction (second direction Y).

A lower injection channel recess 17 extending along the longitudinal direction (first direction X) of the lower metal sheet 10 is formed on the upper surface of the lower injection protrusion 16 . The lower injection channel recess 17 is formed as a non-penetrating recess formed by half etching from the upper surface side of the lower injection protrusion 16 . The outer end of the lower injection flow path recess 17 (the end opposite to the lower steam flow path recess 12) is used to evacuate the sealed space 3 or to introduce the liquid working fluid 2 into the sealed space 3. An opening 17a for injection is formed. This opening 17a communicates the lower injection channel recess 17 with the outside of the vapor chamber 1, and is open toward the outside (the opposite side of the lower vapor flow channel recess 12).

Bank portions 51 are formed on both sides of the lower injection channel recess 17 in the width direction (second direction Y). This bank portion 51 constitutes the walls on both sides of the lower injection channel recessed portion 17 . The bank portion 51 is an area that is not etched, and its upper surface is formed on the same plane as the upper surface 10a of the lower metal sheet 10.

The length (X distance in the first direction) L1 of the lower injection protrusion 16 may be, for example, 5 mm to 30 mm, preferably 5 mm to 20 mm, and the width (Y distance in the second direction) W8 of the lower injection protrusion 16 is , for example, 4 mm to 15 mm, preferably 4 mm to 10 mm. Further, the width w9 of the lower injection channel recess 17 is, for example, 1 mm to 10 mm, preferably 1 mm to 6 mm. Note that the width w9 means the dimension of the lower injection channel recess 17 in the second direction Y, and corresponds to the dimension in the vertical direction in FIG. 4, for example. By setting L1 to 5 mm or more, workability during evacuation of the sealed space 3 is improved, and by setting L1 to 30 mm or less, problems such as deformation are less likely to occur during work such as evacuation. Furthermore, by setting w8 to 4 mm or more, it is possible to obtain a sufficient width of the bank portion 51 for bonding while ensuring the width w9 of the lower injection channel recess 17, and by setting w8 to 15 mm or less, evacuation, etc. The work becomes easier. By setting w9 to 1 mm or more, the cross-sectional area of the injection flow path becomes wider, allowing deaeration work and injection work of hydraulic fluid 2 to be performed efficiently and quickly. By setting w9 to 10 mm or less, leakage after caulking occurs. It becomes difficult.

The width w9 of the lower injection channel recess 17 may be wider than the width w7 of the lower steam passage 81 described above. In this case, for example, the width w7 is 0.05 mm to 2.0 mm, and the width w9 is 1 mm to 10 mm. Further, it is preferable that the width w9 of the lower injection channel recess 17 is at least 1.5 times the width w7 of the lower steam passage 81. More specifically, for example, when the width w7 is 0.05 mm, the width w9 may be 1 mm to 6 mm, preferably 1 mm to 3 mm. Further, for example, when the width w7 is 2 mm, the width w9 may be 3.5 mm to 10 mm, preferably 3.5 mm to 6 mm. In this way, by making the width w9 of the lower injection channel recess 17 wider than the width w7 of the lower steam passage 81, degassing from the sealed space 3 and injection of the working fluid 2 into the sealed space 3 can be quickly performed. can be done.

Note that the width w9 of the lower injection channel recess 17 refers to the width at the widest part of the lower injection channel recess 17, and refers to, for example, the maximum distance between both bank portions 51. Similarly, the width w7 of the lower steam passage 81 refers to the width at the widest part of the lower steam passage recess 12.

Next, the configuration of the lower injection channel recess 17 will be further described with reference to FIGS. 6 and 7. As shown in FIG. 6, an inlet region 52, an intermediate region 53, and a caulking region 54 are formed in the lower injection channel recess 17 along the longitudinal direction from the opening 17a toward the sealed space 3. ing.

Among these, the inlet region 52 is a region into which the liquid working fluid 2 is poured from the opening 17a, and has a substantially flat bottom surface 17b that directly communicates with the opening 17a and has no irregularities.

The intermediate region 53 is located between the entrance region 52 and the caulking region 54. In this intermediate region 53, a plurality of pillars 55 are provided to protrude from the lower injection channel recess 17. Each support column 55 projects upward from the bottom surface 17b. Each pillar 55 is a region that is not etched, and its upper surface is formed on the same plane as the upper surface 10a of the lower metal sheet 10.
The lower surface 20a of the upper metal sheet 20 is in contact with the upper surface of each support column 55 (see FIG. 7). The plurality of pillars 55 serve to improve the strength of the lower injection channel recess 17 and prevent the lower injection protrusion 16 from deforming and blocking the inside of the lower injection channel recess 17. .
By providing a plurality of columns 55 in this manner, the internal space of the lower injection channel recess 17 is secured, and the degassing of the sealed space 3 and the injection of the working fluid 2 into the sealed space 3 are performed more reliably. be able to.

A plurality of pillars 55 are provided along each of the longitudinal direction (first direction , two in the second direction Y, a total of eight). Although each support column 55 has a rectangular shape in plan view, it is not limited to this, and may have a circular, elliptical, or polygonal shape in plan view. Moreover, although the shapes of the plurality of columns 55 are the same, the shapes of the plurality of columns 55 may be different from each other. The width w10 of each support column 55 may be, for example, 0.1 mm to 2 mm. Furthermore, the spacing p1 between the columns 55 may be, for example, 0.1 mm to 2 mm, and the spacing p2 between the columns 55 and the bank portion 51 may be, for example, 0.1 mm to 2 mm. By setting w10 to 0.1 mm or more, the strength as a support is improved, and by setting w10 to 2 mm or less, degassing work and injection work of the hydraulic fluid 2 can be performed efficiently and quickly. By setting p1 and p2 to 0.1 mm or more, degassing work and injection work of the hydraulic fluid 2 can be performed efficiently and quickly, and by setting p1 and p2 to 2 mm or less, the upper injection protrusion 25 is not deformed during bonding. This is less likely to occur, and it is possible to suppress narrowing of the cross-sectional area of the injection channel.

The caulking area 54 is an area that is closed and sealed by caulking (pressing and plastically deforming) after the hydraulic fluid 2 is injected into the sealed space 3 . The caulking region 54 has a plurality of protrusions 56 that project upward within the lower injection channel recess 17 . Each protrusion 56 is a region that is not etched, and its upper surface is formed on the same plane as the upper surface 10a of the lower metal sheet 10. The lower surface 20a of the upper metal sheet 20 is in contact with the upper surface of each protrusion 56 (see FIG. 7). The plurality of protrusions 56 are deformed by being crushed by caulking and close the lower injection channel recess 17 . By providing the plurality of protrusions 56 in the caulking region 54 in this manner, the sealed space 3 into which the hydraulic fluid 2 is injected can be more reliably sealed.

A plurality of protrusions 56 are formed in each of the longitudinal direction (first direction X) and the width direction (second direction Y) of the lower injection channel recess 17. Each protrusion 56 has a rectangular shape in plan view, but is not limited to this, and may have a circular, elliptical, or polygonal shape in plan view. Further, the width w11 of each protrusion 56 may be, for example, 0.01 mm to 0.5 mm, and the interval p3 between the protrusions 56 may be, for example, 0.01 mm to 0.5 mm. Note that the width w11 of each protrusion 56 is smaller than the width w10 of each support column 55, and the interval p3 between the protrusions 56 is narrower than the interval p1 between the support columns 55. Note that, as described above, since the width w9 of the lower injection channel recess 17 is formed to be sufficiently wider than the width w7 of the lower steam passage 81, the presence of the plurality of protrusions 56 in the caulking region 54 causes It is possible to prevent the work of degassing the sealed space 3 and the work of injecting the hydraulic fluid 2 into the sealed space 3 from being obstructed.

As shown in FIG. 7, the depth d1 of the lower injection channel recess 17 may be, for example, 40 μm to 300 μm. In this case, the depth d1 of the lower injection flow path recess 17 may be deeper than the depth h0 of the lower steam flow path recess 12. In this case, for example, the depth h0 is 10 μm to 200 μm, and the depth d1 is 40 μm to 300 μm. More specifically, for example, when the depth h0 is 0.1 mm, the width w7 may be 0.3 mm to 1.5 mm, preferably 0.5 mm to 1.2 mm. Furthermore, if the depth d1 is 0.15 mm at this time, the width w9 may be 1.3 mm to 10 mm, preferably 1.5 mm to 6 mm. In this way, by making the depth d1 of the lower injection channel recess 17 deeper than the depth h0 of the lower vapor flow channel recess 12, degassing from the sealed space 3 to the lower injection channel recess 17 can be achieved. In addition, the hydraulic fluid 2 can be quickly injected from the lower injection channel recess 17 into the sealed space 3. Note that the depth d1 of the lower injection channel recess 17 refers to the depth at the deepest part of the lower injection channel recess 17, and the depth d1 is the depth at the deepest part of the lower injection channel recess 17, and the depth d1 is the depth between the upper surface 10a of the lower metal sheet 10 and the lower injection flow. This refers to the maximum distance (distance in the Z direction) between the concave portion 17 and the bottom surface 17b. In this embodiment, the depth d1 of the lower injection channel recess 17 corresponds to the depth of the lower injection channel recess 17 in the inlet region 52 and the intermediate region 53. Moreover, the depth h0 of the lower steam flow path recess 12 refers to the depth at the deepest part of the lower steam flow path recess 12.

As shown in FIG. 7, the depth d1 of the lower injection channel recess 17 is the same in the inlet region 52 and the intermediate region 53. As shown in FIG. However, the present invention is not limited thereto, and the depth of the lower injection channel recess 17 in the inlet region 52 may be deeper than the depth of the lower injection channel recess 17 in the intermediate region 53. Further, the depth d2 of the lower injection channel recess 17 in the caulking region 54 is shallower than the depth d1 of the lower injection channel recess 17 in the inlet region 52 and the intermediate region 53. Thereby, the plurality of protrusions 56 can be easily crushed by caulking, and the sealed space 3 into which the hydraulic fluid 2 is injected can be sealed even more reliably. Note that when the injection flow path is closed using a method other than caulking, such as brazing, such a caulking region 54 may not be provided.

Next, the configuration of the upper metal sheet 20 will be explained. In this embodiment, the upper metal sheet 20 is different from the lower metal sheet 10 in that it is not provided with a liquid flow path section 30, which will be described later, and has a different configuration of an upper injection protrusion 25. Below, the structure of the upper metal sheet 20 will be explained in more detail.

As shown in FIGS. 3 and 5, the upper metal sheet 20 has an upper steam passage recess 21 (second steam passage part) provided on the lower surface 20a. This upper vapor flow path recess 21 constitutes a part of the sealed space 3, and is mainly configured to diffuse and cool the vapor generated in the evaporator 11. More specifically, the vapor in the upper vapor flow path recess 21 is diffused in a direction away from the evaporator 11, and most of the vapor is transported toward the peripheral edge where the temperature is relatively low. Further, as shown in FIG. 3, on the upper surface 20b of the upper metal sheet 20, a housing member Ha that constitutes a part of a housing of a mobile terminal or the like is arranged. Thereby, the steam in the upper steam flow path recess 21 is cooled by the outside air via the upper metal sheet 20 and the housing member Ha.

In the present embodiment, as shown in FIGS. 2, 3, and 5, in the upper steam passage recess 21 of the upper metal sheet 20, a A plurality of upper flow path wall portions 22 (second flow path wall portions, second flow path protruding portions) are provided that protrude in the direction). In the present embodiment, an example is shown in which the upper flow path wall portion 22 extends in an elongated shape along the first direction X (the left-right direction in FIG. 5) of the vapor chamber 1. This upper channel wall 22 has a flat lower surface 22a (a contact surface, (protruding end surface). Further, the upper channel wall portions 22 are arranged parallel to each other and spaced apart from each other at equal intervals.

As shown in FIGS. 3 and 5, the upper steam passage recess 21 includes a plurality of upper steam passages 83 (second steam passages) partitioned by the upper passage wall 22. The upper steam passages 83 extend in a long and narrow shape along the first direction X, and are arranged parallel to each other. Both ends of each upper steam passage 83 communicate with an upper communication steam passage 84 extending in a slender shape along the second direction Y, and each upper steam passage 83 communicates with each other via the upper communication steam passage 84. There is. In this way, the steam of the working fluid 2 flows around each upper passage wall 22 (the upper steam passage 83 and the upper communication steam passage 84), and the steam flows toward the peripheral edge of the upper steam passage recess 21. It is configured to be transported and prevents the flow of steam from being obstructed. In addition, in FIG. 3, the cross-sectional shape (cross-section in the second direction Y) of the upper steam passage 83 of the upper steam passage recess 21 is rectangular. However, the shape is not limited to this, and the cross-sectional shape of the upper steam passage 83 may be, for example, curved, semicircular, or V-shaped. Optional. The cross-sectional shape of the upper communicating steam passage 84 is also similar. The width of the upper steam passage 83 (dimension in the second direction Y) and the width of the upper communication steam passage 84 are the same as the width of the lower steam passage 81 and the width of the lower communication steam passage 82, as shown in FIG. may be different, but may be different.

The upper channel wall portion 22 is arranged so as to overlap the corresponding lower channel wall portion 13 of the lower metal sheet 10 in plan view, and is intended to improve the mechanical strength of the vapor chamber 1. Moreover, the upper steam passage 83 is formed so as to overlap the corresponding lower steam passage 81 in a plan view. Similarly, the upper communicating steam passage 84 is formed to overlap the corresponding lower communicating steam passage 82 in plan view.

Note that the width and height of the upper channel wall portion 22 are preferably the same as the width w0 and height h0 of the lower channel wall portion 13 described above, respectively. Here, the bottom surface 21a of the upper steam flow path recess 21 can be called a ceiling surface in the vertical arrangement relationship between the lower metal sheet 10 and the upper metal sheet 20 as shown in FIG. Since it corresponds to the inner surface of the recess 21, it is referred to as a bottom surface 21a in this specification.

As shown in FIGS. 3 and 5, an upper peripheral wall 23 is provided at the peripheral edge of the upper metal sheet 20. As shown in FIGS. The upper peripheral wall 23 is formed to surround the sealed space 3 , particularly the upper steam passage recess 21 , and defines the sealed space 3 . Furthermore, upper alignment holes 24 for positioning the lower metal sheet 10 and the upper metal sheet 20 are provided at each of the four corners of the upper peripheral wall 23 in a plan view. That is, each upper alignment hole 24 is arranged so as to overlap each of the lower alignment holes 15 described above during temporary fixing, which will be described later, and is configured to enable positioning of the lower metal sheet 10 and the upper metal sheet 20. .

The upper injection protrusion 25 is configured to be able to inject the liquid working fluid 2 toward the sealed space 3 by covering the lower injection channel recess 17 of the lower injection protrusion 16 from above. The upper injection protrusion 25 is formed to protrude outward from the end surface of the upper metal sheet 20 in plan view. Note that the upper injection protrusion 25 is formed at a position overlapping the lower injection protrusion 16 when the lower metal sheet 10 and the upper metal sheet 20 are joined to each other.

No injection channel recess is formed on the lower surface of the upper injection protrusion 25 . For this reason, the upper injection protrusion 25 is formed in a flat shape with no irregularities as a whole. That is, the upper injection protrusion 25 is a region that is not entirely etched by the etching process described later, and the lower surface of the upper injection protrusion 25 is formed on the same plane as the lower surface 20a of the upper metal sheet 20.

Note that the present invention is not limited to this, and an upper injection channel recess (injection channel recess) having a shape mirror-symmetrical to the shape of the lower injection channel recess 17 is formed on the lower surface of the upper injection protrusion 25, for example. Good too. Alternatively, the upper injection channel recess (injection channel recess) may be formed on the lower surface of the upper injection protrusion 25 and the lower injection channel recess 17 may not be formed on the lower injection protrusion 16 .

Such lower metal sheet 10 and upper metal sheet 20 are permanently joined to each other, preferably by diffusion bonding. More specifically, as shown in FIG. 3, 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 abut, and the lower peripheral wall 14 and the upper peripheral wall 23 are joined to each other. Thereby, a sealed space 3 in which the working fluid 2 is sealed is formed between the lower metal sheet 10 and the upper metal sheet 20. Further, the upper surface 13a of the lower channel wall portion 13 of the lower metal sheet 10 and the lower surface 22a of the upper channel wall portion 22 of the upper metal sheet 20 are in contact with each other, and correspond to each lower channel wall portion 13. The upper channel wall portions 22 are joined to each other. This improves the mechanical strength of the vapor chamber 1. In particular, since the lower flow path wall portion 13 and the upper flow path wall portion 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. Note that the lower metal sheet 10 and the upper metal sheet 20 may be joined by other methods such as brazing, instead of diffusion bonding, as long as they can be permanently joined.
Note that the term "permanently bonded" is not limited to a strict meaning, and the upper surface 10a of the lower metal sheet 10 is bonded to the extent that the sealing performance of the sealed space 3 can be maintained during operation of the vapor chamber 1. This term is used to mean that the upper metal sheet 20 is joined to the lower surface 20a of the upper metal sheet 20 to the extent that the joint can be maintained.

Next, the configuration of the liquid flow path section 30 will be described in more detail using FIGS. 8 and 9. FIG. 8 is an enlarged plan view of the liquid flow path section 30, and FIG. 9 is a cross-sectional view of the liquid flow path section 30.

As described above, the liquid flow path portion 30 through which the liquid working fluid 2 passes is provided on the upper surface 10a of the lower metal sheet 10 (more specifically, the upper surface 13a of each lower flow path wall portion 13). There is. The liquid flow path portion 30 constitutes a part of the sealed space 3 described above, and communicates with the lower vapor flow path recess 12 and the upper vapor flow path recess 21 . Note that the liquid flow path section 30 is not limited to being provided on all of the lower flow path wall sections 13. For example, there may be a lower channel wall section 13 in which the liquid channel section 30 is not provided.

As shown in FIG. 8, the liquid flow path section 30 has a plurality of main flow grooves 31 that extend parallel to each other, and a communication groove 32 that connects the main flow grooves 31 that are adjacent to each other. Of these, the mainstream groove 31 extends along the mainstream direction of the hydraulic fluid 2 (in this case, the first direction X). Further, the communication groove 32 extends along a direction perpendicular to the mainstream direction of the hydraulic fluid 2 (in this case, the second direction Y), and allows the hydraulic fluid 2 to come and go between the adjacent mainstream grooves 31. It has become. The liquid working fluid 2 passes through the main flow groove 31 and the communication groove 32, respectively. The main stream groove 31 and the communication groove 32 mainly serve to transport the working fluid 2 condensed from the vapor generated in the evaporator 11 toward the evaporator 11 .

Further, in the liquid flow path portion 30, a plurality of convex portions 33 are arranged in a staggered manner in a plan view. Each convex portion 33 is formed so as to be surrounded by the main stream groove 31 and the communication groove 32, respectively. In FIG. 8, the plurality of convex portions 33 have the same shape, and each convex portion 33 is formed in a rectangular shape so that the first direction X is the longitudinal direction when viewed from above. In this embodiment, the arrangement pitch of the convex portions 33 along the main flow direction of the hydraulic fluid 2 (first direction X in this case) is constant.
That is, the plurality of convex portions 33 are arranged at regular intervals in the first direction They are staggered.

It is preferable that the width w1 of the mainstream groove 31 (dimension in the second direction Y) is larger than the width w2 of the convex portion 33 (dimension in the second direction Y). In this case, the ratio of the mainstream groove 31 to the upper surface 13a of the lower channel wall portion 13, the upper surface 14a of the lower peripheral wall 14, and the lower surface 23a of the upper peripheral wall 23 can be increased. Therefore, the cross-sectional area of the mainstream groove 31 in the lower channel wall portion 13 can be increased, and the transport function of the liquid working fluid 2 can be improved. For example, the width w1 of the main groove 31 may be 20 μm to 200 μm, and the width w2 of the convex portion 33 may be 20 μm to 180 μm.

The depth h1 of the main stream groove 31 is preferably smaller than the height h0 (see FIG. 3) of the lower channel wall portion 13 described above. In this case, the capillary action of the mainstream groove 31 can be enhanced. For example, the depth h1 of the mainstream groove 31 is preferably about half the height h0 of the lower channel wall portion 13, and may be 5 μm to 200 μm.

Further, it is preferable that the width w3 of the communication groove 32 (dimension in the first direction X) is smaller than the width w1 of the main groove 31. As a result, while the liquid working fluid 2 is being transported toward the evaporation section 11 in each mainstream groove 31, it is possible to prevent the working fluid 2 from flowing into the communication groove 32, thereby improving the transport function of the working fluid 2. Can be done. On the other hand, if dryout occurs in any of the main stream grooves 31, the hydraulic fluid 2 can be moved from the adjacent main stream groove 31 through the corresponding communication groove 32, and the dry out can be quickly resolved. , the transport function of the hydraulic fluid 2 can be ensured.
That is, the communication groove 32 can perform its function even if the width thereof is smaller than the width of the main groove 31, as long as the communication groove 32 can connect the adjacent main grooves 31 with each other. The width w3 of such a communication groove 32 may be, for example, 180 μm.

The depth of the communication groove 32 (not shown) may be shallower than the depth of the main stream groove 31 depending on its width w3. For example, the depth of the communication groove 32 may be 10 μm to 200 μm. Further, the cross-sectional shape of the main stream groove 31 is not particularly limited, and can be, for example, rectangular, C-shaped, semicircular, semi-elliptical, curved, or V-shaped. The cross-sectional shape of the communication groove 32 is also similar.

As shown in FIG. 9, the liquid flow path portion 30 is formed on the upper surface 13a of the lower flow path wall portion 13 of the lower metal sheet 10. As shown in FIG. On the other hand, in this embodiment, the lower surface 22a of the upper channel wall portion 22 of the upper metal sheet 20 is formed in a flat shape. Thereby, each main stream groove 31 of the liquid flow path section 30 is covered by the flat lower surface 22a. In this case, as shown in FIG. 9, the pair of side walls 35 and 36 of the main stream groove 31 extending in the first direction can be formed, and the capillary action at this corner 37 can be enhanced.

In this embodiment, the liquid flow path section 30 is formed only in the lower metal sheet 10.
On the other hand, the vapor flow path recesses 12 and 21 are formed in both the lower metal sheet 10 and the upper metal sheet 20, respectively. However, the present invention is not limited thereto, and the liquid flow path portion 30 and the vapor flow path recesses 12 and 21 may be formed in at least one of the lower metal sheet 10 and the upper metal sheet 20, respectively.

Note that the shape of the liquid flow path section 30 of the lower metal sheet 10 is not limited to the above.

For example, as shown in FIG. 10, the liquid flow path section 30 includes a plurality of main flow grooves 31 extending parallel to each other and an elongated convex section 33A formed between the main flow grooves 31 adjacent to each other. It's okay. In this case, each convex portion 33A extends along the main flow direction of the hydraulic fluid 2 (first direction X in this case) over substantially the entire length of the liquid flow path portion 30 in the longitudinal direction. Thereby, the liquid working fluid 2 can be efficiently transported toward the evaporation section 11 in each mainstream groove 31. Although not shown, a communication groove is provided in a part of the convex portion 33A, and the communication groove allows each main stream groove 31 to communicate with the lower steam flow path recess 12 or the upper steam flow path recess 21. You can also do this.

The materials used for the lower metal sheet 10 and the upper metal sheet 20 are not particularly limited as long as they have good thermal conductivity; for example, copper (oxygen-free copper), copper alloy, aluminum, or stainless steel may be used. It is preferable to use In this case, the thermal conductivity of the lower metal sheet 10 and the upper metal sheet 20 can be increased, and the heat dissipation efficiency of the vapor chamber 1 can be increased. Further, the thickness of the vapor chamber 1 may be 0.1 mm to 2.0 mm. Although FIG. 3 shows a case where the thickness T1 of the lower metal sheet 10 and the thickness T2 of the upper metal sheet 20 are equal, the invention is not limited to this, and the thickness T1 of the lower metal sheet 10 and the thickness T2 of the upper metal sheet The thicknesses T2 of the metal sheets 20 do not have to be equal.

Next, the operation of this embodiment having such a configuration will be explained. Here, first, the method for manufacturing the vapor chamber 1 will be explained using FIGS. 11(a) to (c) and FIGS. 12(a) to (c). Simplify. Note that FIGS. 11(a) to 11(c) and FIGS. 12(a) to 12(c) show cross sections similar to the cross sectional view of FIG. 3.

First, as shown in FIG. 11(a), as a preparation step, a flat metal material sheet M is prepared.

Subsequently, as shown in FIG. 11(b), a resist film 41 is formed on the upper surface Ma and the lower surface Mb of the metal material sheet M by photolithography, respectively. The resist film 41 formed on the upper surface Ma of the metal material sheet M has a pattern shape corresponding to the lower channel wall portion 13 and the lower peripheral wall 14.

Next, as shown in FIG. 11(c), the metal material sheet M is half-etched to form a lower vapor flow path recess 12 that constitutes a part of the sealed space 3. As a result, a portion of the upper surface Ma of the metal material sheet M that corresponds to the resist opening 41a of the resist film 41 is half-etched. Thereafter, the resist film 41 is removed from the metal material sheet M. As a result, as shown in FIG. 11(c), a lower steam passage recess 12, a lower passage wall 13, and a lower peripheral wall 14 are formed. At the same time, a liquid flow path portion 30 is formed in the lower flow path wall portion 13 by half etching. Note that the width of the portion of the resist opening 41a corresponding to the main groove 31 and the communication groove 32 of the liquid flow path portion 30 is narrow, so that the etching liquid does not go around as much. Therefore, the depths of the main stream groove 31 and the communication groove 32 are formed to be shallower than the depth of the lower steam flow path recess 12. Further, at this time, the lower injection channel recess 17 shown in FIGS. 2 and 4 is also formed by etching at the same time, and the lower metal sheet 10 having a predetermined outer contour shape as shown in FIG. 4 is obtained.

Note that half-etching refers to etching in which the material to be etched is etched halfway in the thickness direction to form a recess that does not penetrate the material to be etched. Therefore, the depth of the recess formed by half etching is not limited to half the thickness of the material to be etched. The thickness of the material to be etched after half etching is, for example, 30% to 70%, preferably 40% to 60%, of the thickness of the material to be etched before half etching.
As the etching solution, 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 can be used.

First, the lower vapor flow path recess 12 is formed in the metal material sheet M by half-etching (first half-etching process), and then, in another etching process (second half-etching process), liquid is applied to the metal material sheet M. A flow path section 30 may also be formed.

On the other hand, although not shown, in the same manner as the lower metal sheet 10, the upper metal sheet 20 is half-etched from the lower surface 20a to form an upper steam passage recess 21, an upper passage wall 22, and an upper peripheral wall 23. Ru. In this way, the upper metal sheet 20 described above is obtained.

Next, as shown in FIG. 12(a), as a temporary fixing step, the lower metal sheet 10 having the lower steam flow path recess 12 and the upper metal sheet 20 having the upper steam flow path recess 21 are opposed to each other. Tighten temporarily.

In this case, first, by using the lower alignment hole 15 (see FIGS. 2 and 4) of the lower metal sheet 10 and the upper alignment hole 24 (see FIGS. 2 and 5) 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, but for example, the lower metal sheet 10 and the upper metal sheet 20 may be fixed by resistance welding to the lower metal sheet 10 and the upper metal sheet 20. It's okay. In this case, as shown in FIG. 12(a), it is preferable to perform spot resistance welding using an electrode rod 40. Laser welding may be used 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 a small amount of organic component. In this way, the lower metal sheet 10 and the upper metal sheet 20 are fixed in a positioned state.

After the temporary fixing, as shown in FIG. 12(b), in a permanent bonding step, the lower metal sheet 10 and the upper metal sheet 20 are permanently bonded by diffusion bonding. Diffusion bonding refers to bonding the lower metal sheet 10 and the upper metal sheet 20 to be bonded, and applying pressure in a controlled atmosphere such as a vacuum or inert gas in a direction to bring the metal sheets 10 and 20 into close contact. This is a method of bonding using the diffusion of atoms that occurs at the bonding surface. Diffusion bonding heats the materials of the lower metal sheet 10 and the upper metal sheet 20 to a temperature close to but below the melting point, thereby avoiding melting and deformation of each metal sheet 10, 20. 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 serve as bonding surfaces and are diffusion bonded. Thereby, a 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 working fluid 2 communicates with the sealed space 3 by the lower injection channel recess 17 (see FIGS. 2 and 4) of the lower injection projection 16 and the upper injection projection 25 (see FIGS. 2 and 5). An injection channel is formed. Furthermore, the upper surface 13a of the lower flow path wall 13 of the lower metal sheet 10 and the lower surface 22a of the upper flow path wall 22 of the upper metal sheet 20 serve as a bonding surface and are diffusion bonded, so that the vapor chamber 1 is Mechanical strength is improved. The liquid flow path portion 30 formed on the upper surface 13a of the lower flow path wall portion 13 remains as a flow path for the liquid working fluid 2.

After permanent bonding, as shown in FIG. 12(c), the hydraulic fluid 2 is injected into the sealed space 3 from the injection part 4 (see FIG. 2) as an encapsulation step. At this time, first, the sealed space 3 is evacuated to reduce the pressure (eg, 5 Pa or less, preferably 1 Pa or less), and then the hydraulic fluid 2 is injected into the sealed space 3. During injection, the working fluid 2 passes through an injection channel formed by the lower injection channel recess 17 of the lower injection protrusion 16 and the upper injection protrusion 25 . For example, the amount of the hydraulic fluid 2 sealed may be 10% to 40% of the total volume of the sealed space 3, depending on the configuration of the liquid flow path section 30 inside the vapor chamber 1. As described above, the width w9 of the lower injection channel recess 17 constituting the injection channel is wider than the width w7 of the lower steam passage 81 (see FIG. 4). Therefore, the work of evacuating the injection flow path to reduce the pressure in the sealed space 3 and the work of injecting the working fluid 2 from the injection flow path into the sealed space 3 can be performed efficiently and in a short time.

Here, if the evacuation time of the sealed space 3 is shortened, there is a possibility that non-condensable gas (for example, air, etc.) in the sealed space 3 may remain without being extracted from the sealed space 3. Furthermore, if the injection time of the hydraulic fluid 2 becomes longer, there is a possibility that non-condensable gas may enter the sealed space 3 together with the hydraulic fluid 2. If non-condensable gas remains in the sealed space 3, the movement of the vapor of the working fluid 2 or the liquid working fluid 2 may be inhibited when the vapor chamber 1 is operated. In this case, it becomes difficult to obtain the desired heat transport efficiency. If the desired heat transport efficiency is not obtained in the heat transport test of the vapor chamber 1, the vapor chamber 1 is determined to be a defective product, and as a result, there is a problem that the yield may decrease. The heat transport test is a test in which heat is applied to the vapor chamber 1, the temperature of each part is measured, and based on the temperature measurement results, it is confirmed whether or not heat transport is being carried out normally within the vapor chamber 1. (For example, see Japanese Patent Application Publication No. 2004-301475).

In contrast, in the present embodiment, as described above, the width w9 of the lower injection channel recess 17 constituting the injection channel is wider than the width w7 of the lower steam passage 81. Therefore, the work of evacuating the injection flow path to reduce the pressure in the sealed space 3 and the work of injecting the working fluid 2 from the injection flow path into the sealed space 3 can be performed efficiently and in a short time. As a result, it is possible to prevent non-condensable gas from remaining in the sealed space 3, thereby preventing a decrease in heat transport efficiency, and as a result, yield can be improved.

After injection of the working fluid 2, the injection channel described above is sealed. In this case, for example, by caulking the caulking region 54 of the lower injection channel recess 17, the plurality of protrusions 56 are deformed so as to be crushed. Thereby, the injection part 4 is closed and the injection channel is sealed, and the sealing of the sealed space 3 is completed. Alternatively, the injection portion 4 may be irradiated with a laser to partially melt the injection portion 4 and seal the injection channel. Alternatively, the injection channel 4 may be closed by brazing to seal the injection flow path. As a result, communication between the sealed space 3 and the outside air is cut off, 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 to the outside. Further, in order to seal the injection part 4 more reliably, laser irradiation or brazing may be performed after the caulking region 54 is caulked. Moreover, after sealing the injection channel, the injection part 4 may be cut at an arbitrary position closer to the opening 17a than the caulking area 54 in the injection part 4.

In the manner described above, the vapor chamber 1 according to this embodiment is obtained.

In this embodiment, an example in which the vapor chamber 1 is manufactured mainly by etching has been described. However, it is not limited to this, and may be manufactured using a 3D printer. For example, the vapor chamber 1 may be manufactured all at once using a 3D printer, or each metal sheet 10, 20 may be manufactured separately using a 3D printer and then joined together.

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

The vapor chamber 1 obtained as described above is installed in a housing of a mobile terminal or the like, and a device D such as a CPU, which is an object to be cooled, is attached to the lower surface 10b of the lower metal sheet 10. Since the amount of the working fluid 2 injected into the sealed space 3 is small, the liquid working fluid 2 inside the sealed space 3 is caused by its surface tension to form on the wall surface of the sealed space 3, that is, in the lower steam passage recess 12. It adheres to the wall surface, the wall surface of the upper vapor flow path recess 21, and the wall surface of the liquid flow path section 30.

When the device D generates heat in this state, the working fluid 2 present in the evaporation section 11 of the lower vapor flow path recess 12 receives heat from the device D. The received heat is absorbed as latent heat, the working fluid 2 evaporates (vaporizes), and vapor of the working fluid 2 is generated. Most of the generated steam diffuses within the lower steam flow path recess 12 and the upper steam flow path recess 21 that constitute the sealed space 3 (see solid line arrows in FIG. 4). The vapor in the upper vapor flow path recess 21 and the lower vapor flow path recess 12 leaves the evaporator 11, and most of the vapor is transported toward the peripheral edge of the vapor chamber 1 where the temperature is relatively low. The diffused vapor radiates heat to the lower metal sheet 10 and the upper metal sheet 20 and is cooled. The heat received by the lower metal sheet 10 and the upper metal sheet 20 from the steam is transferred to the outside air via the housing member Ha (see FIG. 3).

The steam radiates heat to the lower metal sheet 10 and the upper metal sheet 20, thereby losing the latent heat absorbed in the evaporator 11 and condensing. The condensed and liquid working fluid 2 adheres to the wall surface of the lower steam flow path recess 12 or the wall surface of the upper steam flow path recess 21 . Here, since the working fluid 2 continues to evaporate in the evaporation section 11, the working fluid 2 in the portion of the liquid flow path section 30 other than the evaporation section 11 is transported toward the evaporation section 11 (Fig. (see dashed arrow). As a result, the liquid working fluid 2 adhering to the wall surface of the lower steam flow path recess 12 and the wall surface of the upper steam flow path recess 21 moves toward the liquid flow path 30 and enters the liquid flow path 30. . Therefore, the working fluid 2 filled in the liquid flow path section 30 obtains a driving force toward the evaporation section 11 due to the capillary action of each mainstream groove 31, and is smoothly transported toward the evaporation section 11.

The working fluid 2 that has reached the evaporator 11 receives heat from the device D again and evaporates. In this way, the working fluid 2 circulates within the vapor chamber 1 while repeating phase changes, that is, evaporation and condensation, thereby transferring and discharging the heat of the device D. As a result, device D is cooled.

As described above, according to the present embodiment, the width w9 of the lower injection channel recess 17 is wider than the width w7 of the lower steam passage 81. Therefore, the cross section of the lower injection channel recess 17 in the width direction (second direction Y) is wider than the cross section of the lower steam passage 81 in the width direction (second direction Y). As a result, when manufacturing the vapor chamber 1, the work of evacuating the injection channel to evacuate the sealed space 3 and the subsequent work of injecting the hydraulic fluid 2 into the sealed space 3 can be performed efficiently and quickly. . Particularly, when the width w9 of the lower injection channel recess 17 is set to 1.5 times or more the width w7 of the lower steam passage 81, such an effect can be significantly obtained.

Further, according to the present embodiment, since the plurality of support columns 55 are provided protruding from the lower injection channel recess 17, deformation of the lower injection channel recess 17 can be suppressed. As a result, when manufacturing the vapor chamber 1, it is possible to prevent deformation of the lower injection channel recess 17 from interfering with degassing the sealed space 3 or injecting the working fluid 2 into the sealed space 3. Deaeration work and injection work can be performed efficiently.

Further, according to the present embodiment, a caulking region 54 is formed in the lower injection channel recess 17, and this caulking region 54 has a plurality of protrusions 56. The plurality of protrusions 56 are crushed when the caulking region 54 is caulked after the hydraulic fluid 2 is injected into the sealed space 3 . Thereby, the sealed space 3 can be sealed even more reliably.

Further, according to the present embodiment, the depth d1 of the lower injection channel recess 17 is deeper than the depth h0 of the vapor flow channel recess 12, so the width direction (second The cross-sectional area in the direction Y) is larger than the cross-sectional area in the width direction (second direction Y) of the lower steam passage 81. Thereby, when manufacturing the vapor chamber 1, the work of degassing the sealed space 3 and the work of injecting the working fluid 2 into the sealed space 3 can be performed efficiently.

Further, according to the present embodiment, the liquid flow path portion 30 includes a plurality of main flow grooves 31 that extend parallel to each other, and a communication groove 32 that connects the main flow grooves 31 that are adjacent to each other. Thereby, the liquid working fluid 2 flows back and forth between the mainstream grooves 31 adjacent to each other, and occurrence of dryout in the mainstream grooves 31 is suppressed. Therefore, a capillary action is applied to the working fluid 2 in each mainstream groove 31, and the working fluid 2 is smoothly transported toward the evaporation section 11.

Further, according to the present embodiment, the plurality of convex portions 33 are arranged in a staggered manner in the liquid flow path section 30 in a plan view. Thereby, the capillary action acting on the working fluid 2 in the mainstream groove 31 can be equalized in the width direction of the mainstream groove 31. That is, since the plurality of convex portions 33 are arranged in a staggered manner in a plan view, the communication grooves 32 are connected to both sides of the main groove 31 alternately. Therefore, unlike the case where the communication grooves 32 are connected to the same position on both sides of each main stream groove 31, it is possible to prevent the communication grooves 32 from losing capillary action in the direction toward the evaporation section 11. Therefore, at the intersection between the main flow groove 31 and the communication groove 32, it is possible to suppress the capillary action from being reduced, and it is possible to continuously apply the capillary action to the working fluid 2 heading toward the evaporation section 11.

Further, since the pressure inside the sealed space 3 is reduced as described above, the lower metal sheet 10 and the upper metal sheet 20 are under pressure from the outside air in a direction in which they are recessed inward in the thickness direction. Here, if the communication grooves 32 are connected to the same position on both longitudinal sides of each main groove 31, the lower metal sheet 10 and the upper metal sheet 20 are connected in a direction parallel to the communication grooves 32. It is possible that it is recessed inward in the thickness direction. In this case, the flow path cross-sectional area of each mainstream groove 31 becomes small, and the flow path resistance of the working fluid 2 may increase. On the other hand, in the present embodiment, a plurality of convex portions 33 are arranged in a staggered manner in the liquid flow path section 30 in a plan view. As a result, even if the lower metal sheet 10 and the upper metal sheet 20 are recessed inward in the thickness direction along the communication groove 32, the recess is prevented from crossing the main groove 31, and the main groove 31 is A cross-sectional area of the flow path can be secured, and the flow of the hydraulic fluid 2 is prevented from being obstructed.

Next, each modification of the vapor chamber will be explained with reference to FIGS. 13 and 14. In FIGS. 13 and 14, the same parts as in FIGS. 1 to 12 are given the same reference numerals, and detailed explanations will be omitted.

(Modification 1)
FIG. 13 shows a vapor chamber 1A according to a modified example (modified example 1). In the vapor chamber 1A shown in FIG. 13, unlike the embodiment shown in FIGS. 1 to 12, the upper metal sheet 20 does not have an upper vapor flow path recess 21 formed therein. Although not shown in FIG. 13, the width of the injection channel recess (lower injection channel recess 17 or upper injection channel recess) is wider than the width of the lower steam passage 81. In this case, it becomes possible to reduce the thickness of the upper metal sheet 20, and thereby the thickness of the vapor chamber 1 as a whole can be reduced.

(Modification 2)
FIG. 14 shows a vapor chamber 1B according to another modification (modification 2). In the vapor chamber 1B shown in FIG. 14, unlike the embodiment shown in FIGS. It is provided on the upper surface 10a of the sheet 10. Further, the liquid flow path portion 30 is formed not only in a region of the upper surface 10 a that faces the upper flow path wall portion 22 but also in a region that faces the upper vapor flow path recess 21 . Although not shown in FIG. 14, the width of the injection channel recess (lower injection channel recess 17 or upper injection channel recess) is wider than the width of the upper vapor flow channel recess 21. In this case, the number of mainstream grooves 31 constituting the liquid flow path portion 30 can be increased, and the transport function of the liquid working fluid 2 can be improved. However, the area where the liquid flow path portion 30 is formed is not limited to the area shown in FIG. 14, and may be any area as long as it can ensure the transport function of the liquid working fluid 2. Furthermore, the thickness of the lower metal sheet 10 can be made thinner, and thereby the thickness of the vapor chamber 1 as a whole can be made thinner.

(Modification 3)
FIG. 15 is a diagram showing a vapor chamber 1C according to another modification (modification 3), and corresponds to FIG. 7 described above. In the vapor chamber 1C shown in FIG. 15, unlike the embodiment shown in FIGS. 1 to 12, the shape of each protrusion 56 in the caulking region 54 is approximately the same as the shape of each support column 55 in the intermediate region 53. . Further, the depth of the lower injection channel recess 17 in the caulking region 54 is the same as the depth d1 of the lower injection channel recess 17 in the inlet region 52 and the intermediate region 53. In this case, by widening the interval p3 between the protrusions 56 and deforming the lower injection channel recess 17, it is possible to efficiently deaerate the sealed space 3 and inject the working fluid 2 into the sealed space 3. .

(Modification 4)
FIG. 16 is a diagram showing a vapor chamber 1D according to another modification (modification 4), and corresponds to FIG. 7 described above. In the vapor chamber 1D shown in FIG. 16, unlike the embodiment shown in FIGS. In addition, it is the same as the depth h0 of the steam flow path recess 12. In this case, since the depth d1 of the lower injection channel recess 17 and the depth h0 of the vapor flow channel recess 12 are the same, the degassing work in the sealed space 3 is facilitated by the deformation of the lower injection channel recess 17. The operation of injecting the hydraulic fluid 2 into the sealed space 3 can be performed smoothly.

(Second embodiment)
Next, a vapor chamber, an electronic device, and a vapor chamber metal sheet according to a second embodiment of the present invention will be described using FIGS. 17 to 19.

In the second embodiment shown in FIGS. 17 to 19, an intermediate metal sheet is interposed between the lower metal sheet and the upper metal sheet, and one of the lower metal sheet and the upper metal sheet has a steam flow path. The main difference is that a recess is formed and a liquid flow path is formed on the other side, and a communication portion that communicates the vapor flow path recess and the liquid flow path is provided in the intermediate metal sheet. The configuration is substantially the same as the first embodiment shown in FIGS. 1 to 16. Note that in FIGS. 17 to 19, the same parts as those in the first embodiment shown in FIGS. 1 to 16 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 17, in this embodiment, an intermediate metal sheet 70 (third metal sheet) is provided between lower metal sheet 10 (first metal sheet) and upper metal sheet 20 (second metal sheet). ) is mediated. That is, in the vapor chamber 1 according to this embodiment, the lower metal sheet 10, the intermediate metal sheet 70, and the upper metal sheet 20 are laminated in this order. The intermediate metal sheet 70 is provided on the lower metal sheet 10 and the upper metal sheet 20 is provided on the intermediate metal sheet 70. In addition, in FIG. 17, illustration of the hydraulic fluid 2 is omitted in order to make the drawing clear. The same applies to FIGS. 20, 22, and 25, which will be described later.

The intermediate metal sheet 70 has a lower surface 70a (first surface) provided on the side of the lower metal sheet 10, and an upper surface 70b (first surface) provided on the side opposite to the lower surface 70a and provided on the side of the upper metal sheet 20. 2nd page) and . Among these, the lower surface 70a is overlapped with the upper surface 10a of the lower metal sheet 10, and the upper surface 70b is overlapped with the lower surface 20a of the upper metal sheet 20.
The lower metal sheet 10 and the intermediate metal sheet 70 are joined by diffusion bonding, and the intermediate metal sheet 70 and the upper metal sheet 20 are joined by diffusion bonding. Intermediate metal sheet 70 may be formed from a similar material as lower metal sheet 10 and upper metal sheet 20. The thickness of the intermediate metal sheet 70 is, for example, 10 μm to 300 μm.

The sealed space 3 is formed between the lower metal sheet 10 and the upper metal sheet 20, and a part of the sealed space 3 is also formed in the intermediate metal sheet 70. In this embodiment, the sealed space 3 includes a vapor flow path section 80 through which the vapor of the working fluid 2 mainly passes, and a liquid flow path section 30 through which the liquid working fluid 2 mainly passes. The vapor flow path section 80 and the liquid flow path section 30 communicate with each other so that the working fluid 2 can flow back. The steam flow path section 80 has a lower steam flow path recess 12 (first steam flow path section) and an upper steam flow path recess 21 (second steam flow path section).

The lower metal sheet 10 including the lower vapor flow path recess 12 and the liquid flow path 30 can have the same configuration as the lower metal sheet 10 in the first embodiment shown in FIGS. 1 to 16. . Therefore, detailed explanation will be omitted here.

In this embodiment, upper metal sheet 20 is not provided with liquid flow path section 30 . Further, the upper metal sheet 20 has an upper steam passage recess 21 (second steam passage part) provided on the lower surface 20a. A plurality of upper passage protrusions 90 (second passage protrusions) that protrude downward (in a direction perpendicular to the bottom face 21a) from the bottom surface 21a of the upper steam passage recess 21 are provided in the upper steam passage recess 21. ing. The upper channel protrusion 90 is a portion where the material of the upper metal sheet 20 remains without being etched in the half-etching process.

As shown in FIG. 17, the upper channel protrusion 90 has a lower surface 90a located on the same plane as the lower surface 20a of the upper metal sheet 20. As shown in FIG. This lower surface 90a is in contact with the upper surface 70b of the intermediate metal sheet 70. This improves the mechanical strength of the vapor chamber 1 when the pressure in the sealed space 3 is reduced.

As shown in FIG. 18, in this embodiment, the upper channel protrusions 90 are arranged in a staggered manner when viewed from above. This allows the vapor of the working fluid 2 to flow around the upper channel protrusion 90, and prevents the flow of the vapor from being obstructed. Further, the planar shape of the lower surface of the upper flow passage protrusion 90 is circular, and in this respect as well, the flow of the vapor of the working fluid 2 is suppressed from being obstructed. Note that the planar shape of the upper channel protrusion 90 is not limited to a circular shape as long as the flow of the vapor of the working fluid 2 can be suppressed from being obstructed.

As shown in FIG. 19, the intermediate metal sheet 70 is provided with a communication hole 71 (communication portion) that communicates the upper vapor flow path recess 21 and the liquid flow path portion 30. The communication hole 71 passes through the intermediate metal sheet 70 and constitutes a part of the sealed space 3 described above. Further, the communication holes 71 are arranged between the upper channel protrusions 90 that are adjacent to each other in a plan view, and the communication holes 71 are arranged in a staggered manner in a plan view.

As shown in FIG. 17, the communication hole 71 extends from the upper surface 70b of the intermediate metal sheet 70 to the lower surface 70a. As a result, the liquid working fluid 2 generated by condensation from the vapor of the working fluid 2 in the upper steam passage concave portion 21 passes through the communication hole 71 and enters the main stream groove 31 of the liquid passage portion 30. It is configured. On the other hand, the vapor of the working fluid 2 evaporated in the evaporator 11 is not only diffused in the lower vapor flow path recess 12 but also can be diffused into the upper vapor flow path recess 21 through the communication hole 71. There is.

The communication hole 71 may be formed by etching from the upper surface 70b of the intermediate metal sheet 70. In this case, the communication hole 71 may be curved so as to swell toward the lower surface 70a. Alternatively, the communication hole 71 may be etched from the lower surface 70a of the intermediate metal sheet 70, and in this case, it may be curved so as to swell toward the upper surface 70b. Furthermore, the communication hole 71 may be formed by half etching from the lower surface 70a and half etching from the upper surface 70b. In this case, the portion of the communication hole 71 on the upper surface 70b side and the portion on the lower surface 70a side may have different shapes or sizes. In this embodiment, as shown in FIG. 19, an example is shown in which the planar shape of the communication hole 71 is circular. When the diameter φ of the communication hole 71 is the minimum diameter in the range extending from the upper surface 70b to the lower surface 70a, the diameter φ of the communication hole 71 may be, for example, 50 μm to 2000 μm. Note that the planar shape of the communication hole 71 is not limited to a circular shape.

As shown in FIG. 19, in this embodiment, the communication hole 71 is connected to a part of one lower steam passage 81 of a pair of adjacent lower steam passages 81 and a lower part of the other lower steam passage 81 in a plan view. It partially overlaps with the side steam passage 81. As a result, a pair of adjacent lower steam passages 81 communicate with each other via the communication hole 71. Therefore, the flow passage cross-sectional area of the communication hole 71 can be increased, and the vapor of the working fluid 2 can be smoothly diffused into the upper steam flow passage recess 21. Note that the communication hole 71 may overlap a portion of each of the three or more lower steam passages 81 so that these lower steam passages 81 communicate with each other.

Further, as shown in FIG. 19, the intermediate metal sheet 70 is provided with intermediate alignment holes 72 for positioning each of the metal sheets 10, 20, and 70. That is, each intermediate alignment hole 72 is arranged so as to overlap each of the lower alignment holes 15 and upper alignment holes 24 described above at the time of temporary fixing, making it possible to position each metal sheet 10, 20, 70. .

In addition, in this embodiment, the injection part 4 may be formed similarly to the injection part 4 of the first embodiment shown in FIGS. 1 to 16. That is, the lower metal sheet 10 has a lower injection protrusion 16 , and a lower injection channel recess (injection channel recess) 17 is formed on the upper surface of the lower injection protrusion 16 . The upper metal sheet 20 has an upper injection protrusion 25, but the lower surface of the upper injection protrusion 25 is formed in a flat shape without any recess.

The intermediate metal sheet 70 has an intermediate injection projection 75 projecting laterally from the end surface. However, the upper and lower surfaces of this intermediate injection protrusion 75 have no recesses and have the same thickness as the intermediate metal sheet 70 before processing. The upper and lower surfaces of the intermediate injection protrusion 75 are formed in a flat shape. The lower injection channel recess 17 and the intermediate injection protrusion 75 together form an injection channel for the working fluid 2 when the lower metal sheet 10 and the intermediate metal sheet 70 are joined. When the lower metal sheet 10, the upper metal sheet 20 and the intermediate metal sheet 70 are joined, each injection projection 16, 25, 75 is adapted to overlap one another. The middle injection protrusion 75 can be formed similarly to the upper injection protrusion 25.

However, it is not limited to this. For example, in addition to or instead of the lower injection channel recess 17, an injection channel recess (injection channel recess) may be formed on the lower surface of the upper injection protrusion 25. Alternatively, instead of such an injection part 4, an injection hole may be provided in the lower metal sheet 10 or the upper metal sheet 20, and the working fluid 2 may be injected from this injection hole.

In addition, in the vapor chamber 1 according to the present embodiment, the lower vapor flow path recess 12 and the liquid flow path section 30 of the lower metal sheet 10, and the upper vapor flow path recess 21 of the upper metal sheet 20 are arranged as shown in FIGS. It can be formed in the same manner as the first embodiment shown in FIG. Furthermore, the communicating holes 71 in the intermediate metal sheet 70 can also be formed by etching. Thereafter, the lower metal sheet 10 and the upper metal sheet 20 are joined via the intermediate metal sheet 70. That is, the lower metal sheet 10 and the intermediate metal sheet 70 are diffusion bonded, and the upper metal sheet 20 and the intermediate metal sheet 70 are diffusion bonded. This forms a sealed space 3. Note that the lower metal sheet 10, the intermediate metal sheet 70, and the upper metal sheet 20 may be diffusion bonded all at once.

As described above, according to the present embodiment, the intermediate metal sheet 70 is interposed between the lower metal sheet 10 and the upper metal sheet 20, and the upper steam flow path recess 21 is provided in the lower surface 20a of the upper metal sheet 20. , a liquid flow path section 30 is provided on the upper surface 10a of the lower metal sheet 10. A communication hole 71 is provided in the intermediate metal sheet 70 to communicate the upper vapor flow path recess 21 and the liquid flow path section 30. As a result, even when the vapor chamber 1 is composed of three metal sheets 10, 20, and 70, the working fluid 2 can be refluxed in the vapor chamber 1 while repeating phase changes in the sealed space 3. , the heat of device D can be transferred and dissipated. Moreover, since the upper vapor flow path recesses 21 of the upper metal sheet 20 are widely connected, the vapor of the working fluid 2 can be smoothly diffused, and the heat transport efficiency can be improved.

Further, according to the present embodiment, the width w9 of the lower injection channel recess 17 is wider than the width w7 of the lower steam passage 81, similar to the first embodiment shown in FIGS. 1 to 16. . As a result, when manufacturing the vapor chamber 1, the work of evacuating the injection channel to evacuate the sealed space 3 and the subsequent work of injecting the hydraulic fluid 2 into the sealed space 3 can be performed efficiently and quickly. .

In addition, in the example shown in FIG. 17, the cross-sectional shape of the lower steam flow path recessed part 12 and the cross-sectional shape of the upper steam flow path recessed part 21 are formed in a rectangular shape. However, the present invention is not limited to this, and the cross-sectional shape of the steam flow path recesses 12 and 21 may be formed in a curved shape. The same applies to the main stream groove 31 and the communication groove 32 of the liquid flow path section 30.

Furthermore, in the present embodiment described above, an example in which one intermediate metal sheet 70 is interposed between the lower metal sheet 10 and the upper metal sheet 20 has been described. However, the invention is not limited to this, and two or more intermediate metal sheets 70 may be interposed between the lower metal sheet 10 and the upper metal sheet 20.

(Third embodiment)
Next, a vapor chamber, an electronic device, and a vapor chamber metal sheet according to a third embodiment of the present invention will be described using FIGS. 20 and 21.

The third embodiment shown in FIGS. 20 and 21 differs mainly in that the upper channel protrusion and the communication hole extend in an elongated shape along the first direction. This embodiment is substantially the same as the second embodiment shown in FIGS. 17 to 19. Note that in FIGS. 20 and 21, the same parts as those in the second embodiment shown in FIGS. 17 to 19 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 20, in this embodiment, the upper channel protrusion 90 (second channel protrusion) provided on the upper metal sheet 20 is different from that of the first embodiment shown in FIGS. 1 to 16. It is configured similarly to the upper flow path wall portion 22 in the embodiment. Therefore, in the following, the upper channel protrusion 90 will be referred to as the upper channel wall 22, and a detailed description of the upper metal sheet 20 including the upper channel protrusion 90 will be omitted.

As shown in FIG. 21, in the present embodiment, the communication hole 71 provided in the intermediate metal sheet 70 is formed to extend in an elongated shape along the first direction X. As shown in FIG. Also in this embodiment, the communication hole 71 is arranged between the upper channel wall portions 22 adjacent to each other in plan view. The width w4 (dimension in the second direction Y) of the communication hole 71 may be, for example, 50 μm to 1500 μm. Here, the width w4 of the communication hole 71 is the minimum width in the range extending from the upper surface 70b to the lower surface 70a.

The communication hole 71 in this embodiment overlaps with one of the lower steam passages 81 of the lower steam passage recess 12 in plan view. The communication hole 71 also overlaps with the upper steam passage 83 of the upper steam passage recess 21 which overlaps the lower steam passage 81 in plan view. That is, the communication hole 71 is provided between the lower steam passage 81 and the upper steam passage 83, which overlap with each other, so as to overlap them. Therefore, the steam of the working fluid 2 in the lower steam passage 81 can quickly reach the upper steam passage 83 via the communication hole 71 and can smoothly diffuse into the upper steam passage 83.

As described above, according to the present embodiment, the intermediate metal sheet 70 is interposed between the lower metal sheet 10 and the upper metal sheet 20, and the upper steam flow path recess 21 is provided in the lower surface 20a of the upper metal sheet 20. , a liquid flow path section 30 is provided on the upper surface 10a of the lower metal sheet 10. A communication hole 71 is provided in the intermediate metal sheet 70 to communicate the upper vapor flow path recess 21 and the liquid flow path section 30. As a result, even when the vapor chamber 1 is composed of three metal sheets 10, 20, and 70, the working fluid 2 can be refluxed in the vapor chamber 1 while repeating phase changes in the sealed space 3. , the heat of device D can be transferred and dissipated.

Further, according to the present embodiment, the width w9 of the lower injection channel recess 17 is wider than the width w7 of the lower steam passage 81, similar to the first embodiment shown in FIGS. 1 to 16. . As a result, when manufacturing the vapor chamber 1, the work of evacuating the injection channel to evacuate the sealed space 3 and the subsequent work of injecting the hydraulic fluid 2 into the sealed space 3 can be performed efficiently and quickly. .

(Fourth embodiment)
Next, a vapor chamber, an electronic device, and a vapor chamber metal sheet according to a fourth embodiment of the present invention will be described using FIGS. 22 to 25.

In the fourth embodiment shown in FIGS. 22 to 25, an intermediate metal sheet is interposed between the lower metal sheet and the upper metal sheet, and a plurality of vapors are formed on at least one of the lower surface and the upper surface of the intermediate metal sheet. A vapor flow path section including a passageway is formed, a liquid flow path section is formed on at least one of the lower surface and the upper surface of the intermediate metal sheet, and an injection liquid flow path section is formed on at least one of the lower surface and the upper surface of the intermediate metal sheet. The main difference is that the width of the injection channel portion is wider than the width of the steam passage, and the other configurations are substantially the same as the second embodiment shown in FIGS. 17 to 19. Note that in FIGS. 22 to 25, the same parts as those in the second embodiment shown in FIGS. 17 to 19 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 22, in this embodiment, the steam flow path section 80 is provided on the upper surface 70b of the intermediate metal sheet 70. That is, the steam flow path section 80 according to the present embodiment is formed to extend from the upper surface 70b to the lower surface 70a of the intermediate metal sheet 70, and penetrates the intermediate metal sheet 70. The liquid flow path section 30 is provided on the lower surface 70a of the intermediate metal sheet 70. Therefore, the intermediate metal sheet 70 according to this embodiment is sometimes referred to as a wick sheet. The vapor flow path section 80 and the liquid flow path section 30 communicate with each other so that the working fluid 2 can flow back.

As shown in FIGS. 23 and 24, the intermediate metal sheet 70 includes a frame portion 73 formed into a rectangular frame shape in plan view, and a plurality of lands 74 provided within the frame portion 73. are doing. The frame portion 73 and the land portion 74 are portions where the material of the intermediate metal sheet 70 remains without being etched when the intermediate metal sheet 70 is etched. The land portions 74 extend in an elongated shape along the first direction X, and a plurality of land portions 74 are arranged within the steam flow path portion 80 . The land portions 74 are supported by each other and by the frame portion 73 via a support portion (not shown). The support portion is formed so as to suppress the flow of steam of the working fluid 2 flowing through the intermediate steam passage 85, which will be described later, from being obstructed. For example, the support portion may be formed in a part of the range extending from the upper surface 70b to the lower surface 70a of the intermediate metal sheet 70 in the vertical direction in FIG.

The steam flow path portion 80 includes a plurality of intermediate steam passages 85 (third steam passage, steam passage) partitioned by the land portion 74. The intermediate steam passages 85 extend in a long and narrow shape along the first direction X, and are arranged parallel to each other. Both ends of each intermediate steam passage 85 communicate with an intermediate communication steam passage 86 extending in a slender shape along the second direction Y, and each intermediate steam passage 85 communicates with each other via the intermediate communication steam passage 86. There is. In this way, the steam of the working fluid 2 flows around each land portion 74 (the intermediate steam passage 85 and the intermediate communication steam passage 86), and the steam is transported toward the peripheral edge of the steam flow path portion 80. This structure prevents the flow of steam from being obstructed. In addition, in FIG. 22, the cross-sectional shape (cross-section in the second direction Y) of the intermediate steam passage 85 is rectangular. However, the cross-sectional shape of the intermediate steam passage 85 may be, for example, curved, semicircular, or V-shaped, as long as the vapor of the working fluid 2 can be diffused. Optional. The same applies to the intermediate communication steam passage 86. The intermediate steam passage 85 and the intermediate communication steam passage 86 can be formed by etching similarly to the communication hole 71 in the second embodiment shown in FIGS. 17 to 19, and have the same cross-sectional shape as the communication hole 71. can have

The width w5 (dimension in the second direction Y) of the land portion 74 of the intermediate metal sheet 70 may be, for example, 50 μm to 2000 μm when the width w5 is the maximum dimension in the range extending from the upper surface 70b to the lower surface 70a. The width w6 (dimension in the second direction Y) of the intermediate steam passage 85 may be, for example, 50 μm to 2000 μm when it is the minimum dimension in the range extending from the upper surface 70b to the lower surface 70a. The same applies to the width (dimension in the first direction X) of the intermediate communication steam passage 86.

The liquid flow path section 30 is provided in the land section 74 on the lower surface 70a of the intermediate metal sheet 70. That is, the liquid flow path section 30 is provided on the lower surface of the land section 74.

In the present embodiment, the upper surface 10a of the lower metal sheet 10 is not provided with the lower vapor flow path recess 12, nor is the liquid flow path portion 30 provided therewith. The upper surface 10a is formed in a flat shape. Similarly, the lower surface 20a of the upper metal sheet 20 is not provided with the upper vapor flow path recess 21, nor is the liquid flow path portion 30 provided therewith. The lower surface 20a is formed in a flat shape. The thickness of the lower metal sheet 10 and the upper metal sheet 20 according to this embodiment are, for example, 8 μm to 100 μm.

Further, in the vapor chamber 1 according to the present embodiment, the vapor flow path section 80 and the liquid flow path section 30 of the intermediate metal sheet 70 can be formed by etching. Thereafter, the lower metal sheet 10 and the upper metal sheet 20 are joined via the intermediate metal sheet 70. That is, the lower metal sheet 10 and the intermediate metal sheet 70 are diffusion bonded, and the upper metal sheet 20 and the intermediate metal sheet 70 are diffusion bonded. This forms a sealed space 3.
Note that the lower metal sheet 10, the intermediate metal sheet 70, and the upper metal sheet 20 may be diffusion bonded all at once.

In the present embodiment, an intermediate injection channel section 76 (injection channel section) is formed in a concave shape on the lower surface of the intermediate injection protrusion section 75 that constitutes the injection section 4 . The lower injection channel recess 17 is not formed on the upper surface of the lower injection protrusion 16, and the upper surface is formed in a flat shape. The lower injection protrusion 16 and the intermediate injection channel 76 together form an injection channel for the working fluid 2 when the lower metal sheet 10 and the intermediate metal sheet 70 are joined. As shown in FIG. 24, no injection channel is formed on the upper surface of the intermediate injection protrusion 75, but the intermediate injection channel 76 is formed in addition to or in place of the lower surface of the intermediate injection protrusion 75. Alternatively, it may be formed on the upper surface of the intermediate injection protrusion 75.

The intermediate injection protrusion 75 and the intermediate injection channel 76 can be formed in the same manner as the lower injection protrusion 16 and the lower injection channel recess 17 in the first embodiment. For example, intermediate injection protrusion 75 may have a width w8 and length L1 similar to lower injection protrusion 16. Further, for example, the intermediate injection channel portion 76 may have the same width w9 as the lower injection channel recessed portion 17.

In this embodiment, the width w9 of the intermediate injection channel portion 76 may be wider than the width w6 of the intermediate steam passage 85 described above. In this case, for example, the width w6 is 0.05 mm to 2.0 mm, and the width w9 is 1 mm to 10 mm. Moreover, it is preferable that the width w9 of the intermediate injection flow path portion 76 is at least 1.5 times the width w6 of the intermediate steam passage 85. More specifically, for example, when the width w6 is 0.05 mm, the width w9 may be 1 mm to 6 mm, preferably 1 mm to 3 mm. Further, for example, when the width w6 is 2 mm, the width w9 may be 3.5 mm to 10 mm, preferably 1 mm to 6 mm. In this way, by making the width w9 of the intermediate injection flow path portion 76 wider than the width w6 of the intermediate steam passage 85, degassing from the sealed space 3 and injection of the working fluid 2 into the sealed space 3 can be performed quickly. be able to.

The intermediate injection channel portion 76 is not limited to being formed in a concave shape. For example, the intermediate injection channel portion 76 may be formed to extend from the lower surface 70a to the upper surface 70b of the intermediate metal sheet 70 and to penetrate the intermediate metal sheet 70. In this case, the support column 55 may be supported by the bank portion 51 via a support portion (not shown). The protrusion 56 may be formed into a columnar shape and supported by the bank portion 51 via a support portion (not shown).

As described above, according to the present embodiment, the intermediate metal sheet 70 is interposed between the lower metal sheet 10 and the upper metal sheet 20, and the vapor flow path portion 80 is provided on the upper surface 70b of the intermediate metal sheet 70. A liquid flow path section 30 is provided on the lower surface 70a of the intermediate metal sheet 70. As a result, even when the vapor chamber 1 is composed of three metal sheets 10, 20, and 70, the working fluid 2 can be refluxed in the vapor chamber 1 while repeating phase changes in the sealed space 3. , the heat of device D can be transferred and dissipated.

Further, according to the present embodiment, the vapor flow path section 80 is provided on the upper surface 70b of the intermediate metal sheet 70 interposed between the lower metal sheet 10 and the upper metal sheet 20, and the vapor flow path section 80 is provided on the lower surface 70a. A flow path section 30 is provided. This makes it unnecessary to perform etching on the lower metal sheet 10 and the upper metal sheet 20 to form vapor channels and liquid channels. That is, the number of members to be etched can be reduced. Therefore, the manufacturing process of the vapor chamber 1 can be simplified, and the vapor chamber 1 can be easily manufactured. Further, since the vapor flow path section 80 and the liquid flow path section 30 are formed in the intermediate metal sheet 70, the vapor flow path section 80 and the liquid flow path section 30 can be positioned with high accuracy during etching processing.
Therefore, it is not necessary to align the vapor flow path section 80 and the liquid flow path section 30 in the assembly process. As a result, the vapor chamber 1 can be manufactured easily. Further, the height (or depth) of the vapor flow path can be defined by the thickness of the intermediate metal sheet 70, and the vapor chamber 1 can be manufactured easily.

Further, according to the present embodiment, the width w9 of the intermediate injection channel section 76 is wider than the width w6 of the intermediate steam passage 85, similarly to the first embodiment shown in FIGS. 1 to 16. As a result, when manufacturing the vapor chamber 1, the work of evacuating the injection channel to evacuate the sealed space 3 and the subsequent work of injecting the hydraulic fluid 2 into the sealed space 3 can be performed efficiently and quickly. .

Further, according to this embodiment, the steam flow path section 80 extends from the upper surface 70b of the intermediate metal sheet 70 to the lower surface 70a. Thereby, the flow path resistance of the steam flow path section 80 can be reduced. Therefore, the liquid working fluid 2 generated by condensation from the vapor of the working fluid 2 in the steam flow path portion 80 can smoothly enter the main stream groove 31 of the liquid flow path portion 30 . On the other hand, the vapor of the working fluid 2 evaporated in the evaporator 11 can be smoothly diffused into the vapor flow path section 80.

In addition, in this embodiment mentioned above, the liquid flow path part 30 demonstrated the example provided in the lower surface 70a of the intermediate metal sheet 70. However, the present invention is not limited to this, and as shown in FIG. 25, the liquid flow path section 30 may be provided not only on the lower surface 70a but also on the upper surface 70b. In this case, the number of channels for transporting the liquid working fluid 2 to the evaporation section 11 or a portion of the intermediate metal sheet 70 that is close to the evaporation section 11 can be increased, and the transport efficiency of the liquid working fluid 2 can be improved. . Therefore, the heat transport efficiency of the vapor chamber 1 can be improved.

Further, in the present embodiment described above, an example has been described in which the steam flow path section 80 is formed so as to extend from the upper surface 70b to the lower surface 70a of the intermediate metal sheet 70. However, the present invention is not limited to this, and the steam flow path section 80 may be formed as the lower steam flow path recess 12 shown in FIGS. 1 to 16 or as the upper steam flow path recess shown in FIGS. 17 and 18. 21, a concave shape may be formed on the upper surface 70b of the intermediate metal sheet 70. In this case, the intermediate metal sheet 70 may be provided with a communication hole (not shown) that communicates the vapor flow path section 80 with the liquid flow path section 30.

Furthermore, in the present embodiment described above, an example in which one intermediate metal sheet 70 is interposed between the lower metal sheet 10 and the upper metal sheet 20 has been described. However, the invention is not limited to this, and another metal sheet (not shown) may be interposed between the lower metal sheet 10 and the intermediate metal sheet 70, and the upper metal sheet 20 and the intermediate metal sheet 70 may be interposed between the lower metal sheet 10 and the intermediate metal sheet 70. Another metal sheet (not shown) may be interposed between them.

The present invention is not limited to the above-described embodiments and modified examples as they are, but can be implemented by modifying the constituent elements within the scope of the invention at the implementation stage. Moreover, various inventions can be formed by appropriately combining the plurality of constituent elements disclosed in each of the above embodiments and modifications. Some components may be deleted from all the components shown in each embodiment and each modification. Furthermore, in each of the embodiments and modifications described above, the configuration of the lower metal sheet 10 and the configuration of the upper metal sheet 20 may be replaced.

1 Vapor chamber 2 Working fluid 10 Lower metal sheet 12 Lower vapor flow path recess 17 Lower injection flow path recess 20 Upper metal sheet 21 Upper vapor flow path recess 30 Liquid flow path portion 31 Main flow groove 32 Communication groove 33 Convex portion 54 Caulking area 55 Support column 56 Projection 70 Intermediate metal sheet 70a Lower surface 70b Upper surface 71 Communication hole 76 Intermediate injection flow path section 80 Steam flow path section 81 Lower steam passage 85 Intermediate steam passage 90 Upper flow path protrusion D Device E Electronic device H Housing P Intersection Q Buffer area X First direction Y Second direction

Claims (11)

A vapor chamber metal sheet for a vapor chamber having a sealed space in which a working fluid is sealed,
The first page and
a second surface provided on the opposite side to the first surface;
Equipped with
A vapor flow path portion through which vapor of the working fluid passes is formed on the first surface,
An injection channel recess for injecting the liquid working fluid is formed on the first surface,
The injection flow path recess communicates with the steam flow path at one end, and has an opening at the other end,
A plurality of protrusions are formed in a first region of the injection channel recess located on the steam channel side,
A plurality of pillars are formed in a second region of the injection channel recess that is located closer to the opening than the first region,
The distance between the adjacent projections is narrower than the distance between the adjacent pillars.
Metal sheet for vapor chamber. The plurality of protrusions and the plurality of pillars are formed along the width direction of the injection channel recess,
The spacing between the protrusions and the spacing between the pillars are the spacing in the width direction,
The metal sheet for a vapor chamber according to claim 1. The plurality of projections and the plurality of pillars are formed along each of the longitudinal direction and the width direction of the injection channel recess,
The metal sheet for a vapor chamber according to claim 2. A vapor chamber metal sheet for a vapor chamber having a sealed space in which a working fluid is sealed,
The first page and
a second surface provided on the opposite side to the first surface;
Equipped with
A vapor flow path portion through which vapor of the working fluid passes is formed on the first surface,
An injection channel recess for injecting the liquid working fluid is formed on the first surface,
The injection flow path recess communicates with the steam flow path at one end, and has an opening at the other end,
A protrusion is formed in a first region of the injection channel recess located on the vapor channel side,
A strut is formed in a second region of the injection channel recess that is located closer to the opening than the first region,
The width of the protrusion is smaller than the width of the support.
Metal sheet for vapor chamber. The upper surface of the protrusion and the upper surface of the support are on the same plane;
A metal sheet for a vapor chamber according to any one of claims 1 to 4. The steam flow path portion includes a steam flow path recess formed on the first surface,
The depth of the vapor flow path recess is deeper than the depth of the injection flow path recess in the first region.
A metal sheet for a vapor chamber according to any one of claims 1 to 5. The steam flow path portion includes a steam flow path recess formed on the first surface,
The depth of the vapor flow path recess is the same as the depth of the injection flow path recess in the first region and the depth of the injection flow path recess in the second region.
A metal sheet for a vapor chamber according to any one of claims 1 to 5. The steam flow path portion includes a steam flow path recess formed on the first surface,
The depth of the vapor flow path recess is shallower than the depth of the injection flow path recess in the first region and the depth of the injection flow path recess in the second region.
A metal sheet for a vapor chamber according to any one of claims 1 to 5. The steam flow path section includes a plurality of steam passages extending in a first direction, and a communication steam passage extending in a second direction perpendicular to the first direction, in which the respective steam passages communicate with each other,
the injection channel recess communicates with the communication steam passage;
A metal sheet for a vapor chamber according to any one of claims 1 to 8. A vapor chamber having a sealed space in which a working fluid is sealed,
A vapor chamber comprising the vapor chamber metal sheet according to any one of claims 1 to 9. housing and
a device contained within the housing;
and a vapor chamber according to claim 10 in thermal contact with the device.