Thermal device

Abstract

A thermal device according to the present disclosure comprises a ceramic container, a fluid, and a sealing part. The container has an opening positioned on the surface thereof, an internal space positioned in the interior thereof, and a communication passage via which the opening and the internal space communicate. The fluid is positioned within the internal space. The sealing part closes the opening. The sealing part is composed of an inorganic material and has a glass part containing a glass component in at least a portion thereof.

Description

Thermal Devices

[0001] The present disclosure relates to thermal devices.

[0002] Thermal devices that utilize the latent heat of a phase-transforming material are known. For example, a vapor chamber, which is one type of thermal device, transfers heat from a high-temperature portion to a low-temperature portion by utilizing the latent heat generated by the evaporation and condensation of a working fluid sealed inside, thereby releasing heat from a heat-generating component (see Patent Document 1).

[0003] International Publication No. 2022 / 181566

[0004] A thermal device according to one aspect of the present disclosure includes a ceramic container, a fluid, and a sealing portion. The container has an opening located on the surface, an internal space located inside, and a communication path connecting the opening and the internal space. The fluid is located in the internal space. The sealing portion closes the opening. The sealing portion is made of an inorganic material and has a glass portion that contains at least a glass component.

[0005] FIG. 1 is a perspective view of a heat dissipation device according to the first embodiment. FIG. 2 is a view of a first member according to the first embodiment, viewed from the negative Z-axis side in the positive Z-axis direction. FIG. 3 is a view of a second member according to the first embodiment, viewed from the positive Z-axis side in the negative Z-axis direction. FIG. 4 is a view of an intermediate member according to the first embodiment, viewed from the positive Z-axis side in the negative Z-axis direction. FIG. 5 is a view in which the first groove formation region shown in FIG. 2 and the second groove formation region shown in FIG. 3 are superimposed on the intermediate member shown in FIG. 4. FIG. 6 is a view for explaining the flow of working fluid in the heat dissipation device according to the first embodiment. FIG. 7 is a view for explaining the flow of working fluid in the heat dissipation device according to the first embodiment. FIG. 8 is a schematic cross-sectional view showing an example of the configuration of a communication passage according to the first embodiment. FIG. 9 is a schematic cross-sectional view showing the configuration of a sealing portion according to the first embodiment. FIG. 10 is a schematic cross-sectional view showing an example of the configuration of a first passage portion according to the second embodiment. FIG. 11 is a schematic plan view showing an example of the configuration of a first passage portion according to the second embodiment. Fig. 12 is a schematic cross-sectional view showing another example of the configuration of the first passage portion according to the second embodiment. Fig. 13 is a schematic cross-sectional view showing another example of the configuration of the first passage portion according to the second embodiment. Fig. 14 is a schematic cross-sectional view showing another example of the configuration of the first passage portion according to the second embodiment. Fig. 15 is a schematic cross-sectional view showing an example of the configuration of the second passage portion according to the third embodiment. Fig. 16 is a schematic cross-sectional view showing an example of the configuration of the second passage portion according to the fourth embodiment. Fig. 17 is a schematic cross-sectional view showing an example of the configuration of the sealing portion according to the fifth embodiment. Fig. 18 is a schematic cross-sectional view showing an example of the configuration of the sealing portion according to the sixth embodiment.

[0006] Hereinafter, a detailed description will be given of a thermal device according to the present disclosure (hereinafter referred to as an "embodiment") with reference to the drawings. Note that the present disclosure is not limited to the embodiment. Furthermore, the embodiments can be appropriately combined as long as the processing contents are not contradictory. Furthermore, the same components in the following embodiments are given the same reference numerals, and redundant explanations will be omitted.

[0007] Furthermore, in the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision or installation precision.

[0008] In the drawings referred to below, for ease of understanding, the X-axis, Y-axis, and Z-axis directions are defined as being orthogonal to each other, and an orthogonal coordinate system is shown in which the positive Z-axis direction is the vertically upward direction. The rotation direction around the vertical axis is also referred to as the θ direction.

[0009] Patent document 1 discloses a thermal device having a container having an internal space and an opening connected to the internal space, a sealing portion that closes the opening, and a bonding layer made of metal that bonds the sealing portion to the container.

[0010] However, if the thermal device contains metal, the thermal device may act as an antenna and become a source of electromagnetic noise.

[0011] Therefore, there is a need for a thermal device that is less likely to generate electromagnetic noise.

[0012] Below, as an example of a thermal device according to the present disclosure, a heat dissipation device, specifically a vapor chamber, that efficiently transfers heat from a high-temperature area to a low-temperature area by utilizing the latent heat associated with the evaporation and condensation of a fluid will be described.

[0013] First Embodiment First, the overall configuration of a heat dissipation device according to a first embodiment will be described with reference to Fig. 1. Fig. 1 is a perspective view of a heat dissipation device 1 according to the first embodiment.

[0014] 1, the heat dissipation device 1 has a ceramic container 2. The container 2 has a first member 10, a second member 20, and an intermediate member 30. The first member 10, the second member 20, and the intermediate member 30 are all plate-shaped, and are stacked such that the first member 10 and the second member 20 sandwich the intermediate member 30.

[0015] The container 2 has an actuation region 100 and a frame region 200. The actuation region 100 has an internal space located inside the container 2, and this internal space is filled with a fluid, specifically, a working liquid as a phase-change material. The working liquid may be, for example, water, a hydrocarbon compound, an organic liquid (e.g., ethanol, methanol, etc.), or ammonia.

[0016] The frame region 200 is a region that surrounds the active region 100. In other words, the frame region 200 is a region of the heat dissipation device 1 that is outside the active region 100. The active region 100 is generally hollow, whereas the frame region 200 is generally solid.

[0017] The frame region 200 is an area that is intentionally made wide in order to reduce, for example, leakage of working fluid or working fluid vapor from the interface between the first member 10 and the intermediate member 30 or the interface between the second member 20 and the intermediate member 30, or to reduce intrusion of the external atmosphere into the internal space of the operating region 100 from the above-mentioned interfaces (i.e., to ensure airtightness).

[0018] The container 2 has a plurality of (here, two) communication passages 14, 15 that connect the internal space of the operating region 100 with the outside. Of the communication passages 14, 15, for example, the communication passage 14 is used as a working fluid injection hole, and the communication passage 15 is used as a gas discharge hole. In this case, during the manufacturing process of the heat dissipation device 1, working fluid is injected into the internal space of the operating region 100 through the communication passage 14, and as a result, gas present in the internal space of the operating region 100 is discharged to the outside through the communication passage 15. The communication passage 14 is located near one of the four corners of the first member 10, and the communication passage 15 is located near the corner diagonally opposite the communication passage 14.

[0019] It should be noted that the heat dissipation device 1 does not necessarily have to have a plurality of communication paths 14, 15. For example, the heat dissipation device 1 may have only one of the communication paths 14, 15.

[0020] The communication passages 14 and 15 are closed by the sealing portion 5. By closing the communication passages 14 and 15 by the sealing portion 5, the internal space of the heat dissipation device 1 is sealed and the working fluid is sealed in the operating region 100. In this way, the heat dissipation device 1 is a sealed container with a sealed interior.

[0021] The working fluid is filled at a ratio of, for example, 10% by volume to 95% by volume of the total volume of the internal space of the operating region 100. Preferably, the ratio is 30% by volume to 75% by volume. More preferably, the ratio is 40% by volume to 65% by volume. The remaining part of the internal space of the operating region 100 other than the working fluid is in a vacuum state containing some vaporized working fluid. This makes it possible to maintain gas-liquid equilibrium even in high-temperature environments, making it less likely to dry out, and also allows for efficient thermal diffusion even in low-temperature environments, thereby improving thermal diffusivity over a variety of temperature ranges.

[0022] The first member 10, the second member 20, and the intermediate member 30 are made of ceramic. Examples of ceramics that can be used to form the first member 10, the second member 20, and the intermediate member 30 include alumina (Al ２ O ３ ), zirconia (ZrO ２ ), silicon carbide (SiC), silicon nitride (Si ３ N ４ ), aluminum nitride (AlN), cordierite (Mg ２ Al ３ (AlSi ５ O １８ ) or silicon-impregnated silicon carbide (SiSiC), etc. The ceramics constituting the first member 10, the second member 20, and the intermediate member 30 may be single crystals.

[0023] Metallic heat dissipation devices have difficulty in obtaining rigidity due to the material or manufacturing method, making them difficult to thin. Furthermore, because the parts of metallic heat dissipation devices that come into contact with the working fluid are made of metal, there is room for improvement in terms of corrosion resistance. In contrast, the heat dissipation device 1 according to the first embodiment has the first member 10, the second member 20, and the intermediate member 30 all made of ceramic, making it easier to thin the device compared to metallic heat dissipation devices and providing superior corrosion resistance.

[0024] 1, the heat dissipation device 1 is installed with the first member 10 facing upward, but the orientation of the heat dissipation device 1 is not limited to the example of FIG. 1. For example, the heat dissipation device 1 may be installed with the first member 10 facing downward. Furthermore, the heat dissipation device 1 is not limited to being installed horizontally as shown in FIG. 1, but may also be installed vertically.

[0025] In a heat dissipation device having a ceramic container, since ceramic is a brittle material, an important issue is how to ensure durability against stresses generated by, for example, phase transformation of the working fluid.

[0026] To address this issue, in the heat dissipation device 1 according to the first embodiment, the communication paths 14, 15 are located in the frame region 200. The frame region 200 is solid, unlike the operating region 100. By locating the communication paths 14, 15 in the frame region 200, durability can be improved compared to when the communication paths 14, 15 are located in the operating region 100. In this way, the heat dissipation device 1 according to the first embodiment can achieve improved durability.

[0027] Furthermore, according to the heat dissipation device 1 of the first embodiment, a larger effective space can be secured in the operating area 100 compared to when the communicating passages 14, 15 are located in the operating area 100, thereby improving the heat dissipation characteristics.

[0028] Furthermore, since the frame region 200 in which the communication paths 14, 15 are located is made of the same ceramic material as the operating region 100, stress due to differences in thermal expansion is unlikely to occur. Therefore, the heat dissipation device 1 according to the first embodiment has high reliability.

[0029] Next, the configuration of the first member 10 will be described with reference to Fig. 2. Fig. 2 is a view of the first member 10 according to the first embodiment, viewed from the negative Z-axis direction side toward the positive Z-axis direction.

[0030] 2 shows the lower surface of the first member 10, specifically, the surface (third surface) facing the upper surface (first surface) of the intermediate member 30. As shown in FIG. 2, the first member 10 has a lattice-shaped first groove portion 11 on the third surface.

[0031] The first groove portion 11 has a first recess 11a recessed relative to the third surface and a plurality of first protrusions 11b located within the first recess 11a. The first recess 11a is located in the center of the third surface and has, for example, a rectangular outline in plan view. The plurality of first protrusions 11b are arranged vertically and horizontally at intervals within the first recess 11a. The first recess 11a and the plurality of first protrusions 11b form a lattice pattern for the first groove portion 11.

[0032] Hereinafter, the area of ​​the third surface of the first member 10 where the first groove portion 11 is located will be referred to as the "first groove formation area 110." The first groove formation area 110 constitutes part of the operating area 100. The first member 10 also has a rectangular frame-shaped first frame area 210 that surrounds the first groove formation area 110. The first frame area 210 constitutes part of the frame area 200.

[0033] A plurality of (here, two) through holes 141 a, 151 a that penetrate the first member 10 in the thickness direction (here, the Z-axis direction) are located in the first frame region 210. The through hole 141 a constitutes a part of the first passage portion 141 in the communication passage 14, and the through hole 151 a constitutes a part of the first passage portion 151 in the communication passage 15.

[0034] A heat source is disposed in the center of the upper surface (fifth surface) of the first member 10, which is located opposite the lower surface (third surface).

[0035] Next, the configuration of the second member 20 will be described with reference to Fig. 3. Fig. 3 is a view of the second member 20 according to the embodiment, viewed from the positive Z-axis direction side toward the negative Z-axis direction.

[0036] 3 shows the upper surface of the second member 20, specifically, the surface (fourth surface) facing the lower surface (second surface) of the intermediate member 30. As shown in FIG. 3, the second member 20 has a lattice-shaped second groove portion 21 on the fourth surface.

[0037] The second groove portion 21 has a second recess 21a recessed relative to the fourth surface and a plurality of second protrusions 21b located within the second recess 21a. The second recess 21a is located in the center of the fourth surface and has, for example, a rectangular outline in plan view. The plurality of second protrusions 21b are arranged vertically and horizontally at intervals within the second recess 21a. The second recess 21a and the plurality of second protrusions 21b form the second groove portion 21 in a lattice pattern.

[0038] Hereinafter, the region of the fourth surface of the second member 20 where the second groove portion 21 is located will be referred to as the "second groove formation region 120." The second groove formation region 120 constitutes part of the operating region 100. The second member 20 also has a second frame region 220 in the shape of a rectangular frame that surrounds the second groove formation region 120. The second frame region 220 constitutes part of the frame region 200.

[0039] The size of the second groove formation region 120 in the second member 20 is the same as the size of the first groove formation region 110 in the first member 10. In addition, the position of the second groove formation region 120 on the fourth surface of the second member 20 is the same as the position of the first groove formation region 110 on the third surface of the first member 10.

[0040] In this way, by forming the first groove portion 11 and the second groove portion 21 in a lattice shape, it is possible to efficiently circulate the working fluid in the internal space of the heat dissipation device 1. Note that the shapes of the first groove portion 11 and the second groove portion 21 do not necessarily have to be lattice-shaped.

[0041] The second frame region 220 has a plurality of (two in this example) recesses 141b, 151b recessed relative to the upper surface (fourth surface) of the second member 20. The recess 141b constitutes a part of the first passage portion 141 in the communication passage 14, and the recess 151b constitutes a part of the first passage portion 151 in the communication passage 15.

[0042] Groove portions 142b and 152b are located in the second frame region 220. Groove portion 142b is a passage extending in a second direction (here, the Y-axis direction) intersecting the extension direction of first passage portion 141 of communicating passage 14 (first direction, here, the Z-axis direction), with one end opening to recessed portion 141b in first passage portion 141 and the other end opening to the second groove-forming region 120. Groove portion 152b is a passage extending in a second direction (here, the Y-axis direction) intersecting the extension direction of first passage portion 151 of communicating passage 15 (first direction, here, the Z-axis direction), with one end opening to recessed portion 151b in first passage portion 151 and the other end opening to the second groove-forming region 120.

[0043] Next, the configuration of the intermediate member 30 will be described with reference to Fig. 4. Fig. 4 is a view of the intermediate member 30 according to the first embodiment, viewed from the positive side of the Z axis toward the negative side of the Z axis.

[0044] As shown in Fig. 4 , the intermediate member 30 has a third frame region 230 that is rectangular in shape. The third frame region 230 constitutes a part of the frame region 200. The intermediate member 30 also has a central portion 32 that is circular in plan view and located inside the third frame region 230, and a plurality of connecting portions 33 that are located between the central portion 32 and the third frame region 230 and connect the central portion 32 and the third frame region 230. In the example shown in Fig. 4 , the central portion 32 is located at the center of the intermediate member 30. The multiple connecting portions 33 are spaced apart from one another and extend radially from the central portion 32 toward the third frame region 230 while increasing in width.

[0045] The intermediate member 30 further has a plurality of steam holes 36 and a plurality of reflux holes 37. The plurality of steam holes 36 and the plurality of reflux holes 37 each penetrate the upper surface (first surface) and the lower surface (second surface) of the intermediate member 30.

[0046] The multiple steam holes 36 function as part of a flow path for vapor of the working fluid. The multiple steam holes 36 are located between two adjacent connection portions 33. That is, the multiple steam holes 36 and the multiple connection portions 33 are located alternately in the circumferential direction. Like the multiple connection portions 33, the multiple steam holes 36 are spaced apart from one another and extend radially from the central portion 32 toward the third frame region 230 while increasing in width.

[0047] The plurality of reflux holes 37 function as part of the flow path of the working fluid. The reflux holes 37 are minute holes with a smaller opening area than the above-described steam holes 36. Specifically, the reflux holes 37 are small enough to generate capillary action in the working fluid passing through the reflux holes 37.

[0048] A plurality of (here, two) through holes 141c, 151c are positioned in the third frame region 230, penetrating the intermediate member 30 in the thickness direction (here, the Z-axis direction). The through hole 141c constitutes a part of the first passage portion 141 of the communication passage 14, and the through hole 151c constitutes a part of the first passage portion 151 of the communication passage 15.

[0049] Fig. 5 is a diagram in which the first groove formation region 110 shown in Fig. 2 and the second groove formation region 120 shown in Fig. 3 are superimposed on the intermediate member 30 shown in Fig. 4. Note that, for ease of understanding, the communicating passages 14 and 15 are omitted from Fig. 5.

[0050] 5 , the first groove formation region 110 and the second groove formation region 120 overlap with the third frame region 230 of the intermediate member 30. In other words, the first groove formation region 110 and the second groove formation region 120 extend outward from the region in the intermediate member 30 where the multiple steam holes 36 and the multiple return holes 37 are formed (hereinafter referred to as the “hole formation region”).

[0051] In this way, by making the first groove formation region 110 of the first member 10 and the second groove formation region 120 of the second member 20 wider than the hole formation region of the intermediate member 30, the internal space of the heat dissipation device 1 can be expanded outward compared to when the first groove formation region 110 and the second groove formation region 120 are made approximately the same size as the hole formation region.

[0052] The heat source is located in the center of the heat dissipation device 1. Therefore, the temperature of the heat dissipation device 1 decreases the further away from the heat source, i.e., the closer to the outer periphery of the heat dissipation device 1. Furthermore, the vapor of the working fluid condenses into a liquid as it moves to the low-temperature region. Therefore, by expanding the internal space of the heat dissipation device 1 outward, condensation of the working fluid becomes more likely. This makes it less likely for dryout to occur.

[0053] Here, an example has been shown in which the first groove formation region 110 and the second groove formation region 120 extend outward from the hole formation region of the intermediate member 30, but this is not limited to this, and the hole formation region of the intermediate member 30 may extend outward from the first groove formation region 110 and the second groove formation region 120.

[0054] The operating region 100 of the heat dissipation device 1 has an internal space sandwiched between a first groove formation region 110 and a second groove formation region 120, and this internal space is filled with a working fluid. An intermediate member 30 is interposed between the first groove formation region 110 and the second groove formation region 120 of the internal space, thereby dividing the operating region 100 into a first space sandwiched between the first groove formation region 110 and the intermediate member 30, and a second space sandwiched between the second groove formation region 120 and the intermediate member 30. The first space and the second space are connected by a steam hole 36 and a reflux hole 37 formed in the intermediate member 30.

[0055] Next, the flow of working fluid in the heat dissipation device 1 according to the first embodiment will be described with reference to FIGS. 6 and 7. FIGS. 6 and 7 are diagrams for explaining the flow of working fluid in the heat dissipation device 1 according to the first embodiment. Note that FIG. 6 is a diagram in which the third frame region 230 is omitted from the diagram shown in FIG. 5, and FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6. In addition, in FIGS. 6 and 7, the flow of steam is indicated by open arrows, and the flow of liquid is indicated by filled arrows.

[0056] The working fluid is heated by the heat source and vaporized into steam. As described above, the heat source is disposed in the center of the upper surface (fifth surface) of the first member 10 (see FIGS. 1 and 2 ). Therefore, the working fluid vapor is generated in the center of the first space (the space sandwiched between the first member 10 and the intermediate member 30).

[0057] The vapor of the working fluid passes through the first groove portion 11 of the first groove formation region 110, diffusing in the in-plane direction (XY plane direction) of the heat dissipation device 1 (see the open arrows in Figure 6), and moves through the multiple steam holes 36 to the second space (the space sandwiched between the second member 20 and the intermediate member 30) (see the open arrows in Figure 7).

[0058] The vapor that moves to the second space condenses and becomes liquid due to a decrease in temperature. The liquefied working fluid moves through the second groove formation region 120 toward the center of the heat dissipation device 1 due to the capillary force of the second groove portion 21 (see the black arrows in FIG. 6 ). During this process, the working fluid enters the reflux hole 37 and is returned to the first space by the capillary force of the reflux hole 37 (see the black arrows in FIG. 7 ). By repeating the above cycle, the heat dissipation device 1 can transfer heat from the heat source.

[0059] Next, the configuration of the communication passages 14, 15 will be described with reference to Fig. 8. Fig. 8 is a schematic cross-sectional view showing an example configuration of the communication passage 14 according to the first embodiment. While Fig. 8 shows the communication passage 14 as an example, the communication passage 15 also has a similar configuration to the communication passage 14.

[0060] 8 , the communication passage 14 connects the internal space of the operating region 100 with the outside. In other words, the communication passage 14 connects the internal space of the operating region 100 with an opening located on the surface of the container 2. The communication passage 14 has a first passage portion 141 extending from the opening in a first direction (here, the Z-axis direction), and a second passage portion 142 continuing from the first passage portion 141 and opening into the internal space of the operating region 100. The second passage portion 142 extends, for example, in a direction intersecting the first direction (here, the Y-axis direction).

[0061] The first passage portion 141 is formed by a through hole 141a of the first member 10, a through hole 141c of the intermediate member 30, and a recess 141b of the second member 20. The first passage portion 141 will be described in detail later.

[0062] The second passage portion 142 is formed by the groove portion 142b of the second member 20 and the lower surface 302 (second surface) of the intermediate member 30. Note that, although Fig. 8 shows an example in which the recessed portion 141b of the first passage portion 141 is recessed further than the groove portion 142b of the second passage portion 142, the recessed portion 141b and the groove portion 142b may be flush with each other.

[0063] As described above, the communication path 14 has a first path portion 141 extending in a first direction (here, the Z-axis direction) and a second path portion 142 extending in a direction intersecting the first direction (here, the Y-axis direction). In other words, the communication path 14 is curved. Therefore, according to the heat dissipation device 1 according to the first embodiment, even if high pressure occurs in the operating region 100, high pressure is unlikely to be applied to the sealing portion 5, and therefore reliability is high.

[0064] 8 shows an example in which the second passage portion 142 extends in a direction intersecting the first direction (here, the Y-axis direction), but the configuration of the second passage portion 142 is not limited to this. Other configuration examples of the second passage portion 142 will be described later.

[0065] The first passage portion 141 opens to the upper surface of the first member 10 and extends across the first space and the second space of the operating region 100 in the frame region 200. The second passage portion 142 is located on the second space side of the operating region 100 in the frame region 200.

[0066] In the heat dissipation device 1, the pressure in the first space is higher than the pressure in the second space. In other words, the pressure in the second space is lower than the pressure in the first space. Therefore, since the second passage portion 142 is located on the second space side, high pressure is less likely to be applied to the communication passage 14.

[0067] 1, the communication passage 14 is positioned so as to sandwich the operating region 100 between it and the communication passage 15. By arranging the two communication passages 14, 15 in this manner, durability is less likely to decrease locally compared to, for example, when the two communication passages 14, 15 are arranged side by side.

[0068] Next, a description will be given of the configuration of the sealing portion 5. Fig. 9 is a schematic cross-sectional view showing the configuration of the sealing portion 5 according to the first embodiment.

[0069] As shown in FIG. 9 , the sealing portion 5 has a glass portion 51. The glass portion 51 is positioned so as to block the opening of the communicating path 14 on the exterior side. For example, the glass portion 51 may be positioned in the through hole 141a that forms the communicating path 14. The glass portion 51 is made of, for example, an inorganic material. The glass portion 51 may contain a glass component. The glass portion 51 may contain ceramic crystals in addition to the glass component. The glass portion 51 may contain 20% by volume or more of the glass component. The glass portion 51 may be mainly composed of the glass component. In the present disclosure, a "main component" refers to, for example, a material that accounts for 50% by mass or more of the material. When the glass portion 51 contains 50% by volume or more of the glass component, sealing becomes easier.

[0070] The material of the glass portion 51 may be crystallized glass. Examples of the crystallized glass include SiO ２ -CaO system, MgO-B ２ O ３ System, La ２ O ３ -B ２ O ３ -MgO system, La ２ O ３ -B ２ O ３ -ZnO or SiO ２ -CaO-ZnO system materials, etc., may be used, and in particular SiO ２ -MgO-based materials may also be used, which can improve the strength of the glass portion 51.

[0071] As described above, the sealing portion 5 according to the first embodiment is made of an inorganic material, and the through-hole 141a is blocked with the glass portion 51 containing a glass component, thereby sealing the heat dissipation device 1. With this configuration, the entire heat dissipation device 1, including the sealing portion 5, is made of a non-metal, so electromagnetic noise is less likely to be generated even when the heat dissipation device 1 is used to dissipate heat from a high-frequency substrate. Furthermore, because the thermal expansion coefficient of the glass portion 51 is close to that of the ceramic container 2, stress due to the difference in thermal expansion at the temperature of the environment in which the heat dissipation device 1 is used is reduced, improving the reliability of the heat dissipation device 1.

[0072] Although the example shown here uses crystallized glass as the material for the glass portion 51, the material is not limited to this. For example, the glass portion 51 may contain multiple glass components with different softening points. Specifically, the glass portion 51 may have multiple glass components with different softening points dispersed therein. Furthermore, a glass component with a low softening point may be located closer to the external opening of the communicating path 14, and a glass component with a high softening point may be located farther from the external opening of the communicating path 14. This can improve the rigidity of the heat dissipation device 1.

[0073] Glass portion 51 may also contain a ceramic filler. Examples of ceramic fillers that can be used include alumina (aluminum oxide), calcium titanate, and magnesium titanate. Glass portion 51 containing alumina has particularly high rigidity. In this case, the glass portion 51 is made of a material containing a glass component other than the filler.

[0074] Next, the first passage portion 141 and the container 2 will be described with reference to Figure 9. As described above, the first passage portion 141 is formed by the through hole 141a of the first member 10, the through hole 141c of the intermediate member 30, and the recessed portion 141b of the second member 20. Note that the through hole 141a corresponds to a first portion including an opening, and the through hole 141c corresponds to a second portion continuous with the through hole 141a. Furthermore, the recessed portion 141b corresponds to a third portion continuous with the through hole 141c.

[0075] In a cross-sectional view (i.e., the cross-sectional view shown in FIG. 9 ) of the communicating passage 14 cut along the thickness direction (here, the Z-axis direction) of the container 2, the width (width along the Y-axis direction) of the through hole 141a is D1, the width (width along the Y-axis direction) of the through hole 141c is D2, and the width (width along the Y-axis direction) of the recess 141b is D3. The width D2 of the through hole 141c may be different from the width D1 of the through hole 141a. In the example of FIG. 9 , the width D2 of the through hole 141c is smaller than the width D1 of the through hole 141a. Furthermore, the width D3 of the recess 141b may be different from the width D2 of the through hole 141c. In the example of FIG. 9 , the width D3 of the recess 141b is larger than the width D2 of the through hole 141c. In other words, the passage cross-sectional area of ​​the second portion may be different from the passage cross-sectional area of ​​the first portion, and the passage cross-sectional area of ​​the third portion may be different from the passage cross-sectional area of ​​the second portion.

[0076] With this configuration, the glass portion 51 is less likely to enter the operating area 100 from the communication passage 14 .

[0077] Furthermore, glass portion 51 may be located in through-hole 141 a, through-hole 141 c, and recess 141 b. In this case, a step is located between recess 141 b and through-hole 141 c, and therefore, even if force is applied to glass portion 51, glass portion 51 is caught on the step, making it difficult for glass portion 51 to come out of first passage portion 141.

[0078] The container 2 may contain at least one element of the glass components contained in the glass portion 51. The container 2 and the glass portion 51 may contain, for example, an alkaline earth metal element, aluminum, or silicon. In particular, the container 2 and the glass portion 51 containing an alkaline earth metal element have high wettability, thereby improving adhesion. In this way, the container 2 and the glass portion 51 contain a common element, which improves the bonding strength, thereby improving the bonding strength between the container 2 and the glass portion 51.

[0079] Next, an example of a method for manufacturing the heat dissipation device 1 according to the first embodiment will be described. First, green sheets are formed using raw materials for the first member 10, the second member 20, and the intermediate member 30 by a doctor blade method, a roll compaction method, or the like, and a plurality of green sheets are stacked to obtain a laminate.

[0080] Next, the obtained laminate is subjected to laser processing or die punching to obtain molded articles of the first member 10, the second member 20, and the intermediate member 30. For example, by performing laser processing on the laminate, a molded article of the intermediate member 30 can be obtained in which through holes 141c, 151c, a plurality of steam holes 36, and a plurality of reflux holes 37 are formed. Furthermore, by performing laser processing on the obtained laminate, a molded article of the first member 10 in which through holes 141a, 151a and the first groove formation region 110 are formed is obtained. Furthermore, by performing laser processing on the obtained laminate, a molded article of the second member 20 in which recesses 141b, 151b, grooves 142b, 152b, and the second groove formation region 120 are formed is obtained.

[0081] Next, the molded bodies of the first member 10, the second member 20, and the intermediate member 30 are stacked in the order of the second member 20, the intermediate member 30, and the first member 10, and then fired to obtain a sintered body of the container 2 in which the first member 10, the second member 20, and the intermediate member 30 are integrated. In this manner, the first member 10, the second member 20, and the intermediate member 30 are integrally molded. Therefore, since adhesives or the like are not required, a highly reliable heat dissipation device 1 can be obtained.

[0082] The method for obtaining each of the molded bodies of the first member 10, the second member 20, and the intermediate member 30 is not limited to the above-described method, and each molded body may be obtained, for example, by processing green sheets and then stacking the green sheets. In the above example, each of the molded bodies of the first member 10, the second member 20, and the intermediate member 30 is produced individually and then stacked to obtain the molded body of the container 2, but the molded body of the container 2 may also be obtained, for example, by sequentially stacking processed green sheets.

[0083] Next, working fluid is injected into the sintered body through, for example, one of the communication passages 14, 15. Gas present inside the sintered body is discharged to the outside through the other of the communication passages 14, 15 as the working fluid is injected.

[0084] Next, a vacuum pump or other pressure reducing device is used to evacuate the inside of the sintered body via the communicating passages 14, 15. While it is desirable for the inside of the sintered body to be in a vacuum state, it does not need to be in a strict vacuum state; for example, a reduced pressure state close to a vacuum state may be used. Next, with the inside of the sintered body in a vacuum state, the communicating passages 14, 15 are sealed. For example, a paste containing a glass component is placed so as to block the openings of the communicating passages 14, 15, and the communicating passages 14, 15 are sealed by locally heating the paste with light heating such as a laser or far-infrared rays to melt the paste. As a result, the communicating passages 14, 15 are sealed by the sealing portion 5, and the heat dissipation device 1 is obtained.

[0085] As described above, the sealing portion 5 according to the first embodiment is made of an inorganic material, and the glass portion 51 containing a glass component blocks the through-hole 141a, thereby sealing the heat dissipation device 1. With this configuration, the entire heat dissipation device 1, including the sealing portion 5, is made of a non-metal, and therefore electromagnetic noise is unlikely to be generated even when the heat dissipation device 1 is used to dissipate heat from a high-frequency substrate.

[0086] Second Embodiment Fig. 10 is a schematic cross-sectional view showing an example of the configuration of a first passage portion 141 according to a second embodiment. Fig. 11 is a schematic plan view showing an example of the configuration of a first passage portion 141 according to the second embodiment. For ease of understanding, the sealing portion 5 is indicated by a dotted line in Fig. 11. As shown in Figs. 10 and 11, the first passage portion 141 may have a plurality of through holes 141a. The plurality of through holes 141a correspond to a plurality of first branch passages. In other words, the first passage portion 141 may have a plurality of first branch passages.

[0087] Each through hole 141 a has one end opening to the outside and the other end opening to a through hole 141 c. The width (width along the Y-axis direction) of each through hole 141 a may be smaller than the width D2 of the through hole 141 c (see FIG. 9 ).

[0088] In this way, by having multiple through holes 141a in first passage portion 151 of communication path 14, the contact area between glass portion 51 and container 2 is increased compared to when there is only one through hole 141a, thereby improving the bonding strength between glass portion 51 and container 2. In addition, glass portion 51 is less likely to infiltrate from communication path 14 into operating region 100.

[0089] 12 to 14 are schematic cross-sectional views showing other configuration examples of the first passage portion 141 according to the second embodiment.

[0090] 12, the plurality of through holes 141a of the first passage portion 141 may have a tapered shape in which the width decreases from the opening toward the through hole 141c. With this configuration, it is more difficult for the glass portion 51 to penetrate from the first passage portion 141 into the operating region 100.

[0091] As shown in Fig. 13, the first member 10 may be composed of a plurality of plate members 10a, 10b. In this case, the plate member 10a that is open to the outside among the plurality of plate members 10b may have one through-hole 1411a. The plate member 10b that contacts the intermediate member 30 may have a plurality of through-holes 1412a. The plurality of through-holes 1412a open to the through-hole 1411a at one end and to the through-hole 141c at the other end. With this configuration, it is more difficult for the glass portion 51 to penetrate from the first passage portion 141 into the operating region 100.

[0092] As shown in FIG. 14 , the first member 10 may be composed of multiple plate members 10a and 10b. Of the multiple plate members 10b, the plate member 10a that opens to the outside may have multiple through holes 1411a. Furthermore, the plate member 10b that contacts the intermediate member 30 may have multiple through holes 1412a. In this case, the through holes 1411a and the through holes 1412b may be offset in the in-plane direction (XY plane direction) of the first member 10. This configuration increases the contact area between the glass portion 51 and the container 2, improving the bonding strength between the glass portion 51 and the container 2. Furthermore, the glass portion 51 is less likely to infiltrate from the first passage portion 141 into the operating region 100.

[0093] Third Embodiment Fig. 15 is a schematic cross-sectional view showing an example configuration of a second passage portion 142 according to a third embodiment. As shown in Fig. 15, the second passage portion 142 may extend in a direction (Y-axis direction) that intersects with the first direction while meandering. Specifically, the second passage portion 142 may have a fourth portion 142c that extends in a second direction different from the first direction, and a fifth portion 142d that is continuous with the fourth portion 142c and extends in a third direction different from the second direction.

[0094] This configuration can increase the flow resistance of the second passage portion 142. Therefore, it is more difficult for the glass portion 51 to enter the operating region 100 from the communication passage 14.

[0095] Although Figure 15 shows an example in which the second passage portion 142 snakes in the thickness direction of the container 2 (here, the Z-axis direction), the second passage portion 142 may also snake in the in-plane direction of the second member 20 (the XY plane direction).

[0096] 16 is a schematic cross-sectional view showing an example of the configuration of a second passage portion 142 according to a fourth embodiment. Specifically, Fig. 16 shows an enlarged view of the area around the second passage portion 142 on the upper surface (fourth surface) of the second member 20.

[0097] 16, the second passage portion 142 may have a plurality (here, five) of second branch passages 1421-1425. The plurality of second branch passages 1421-1425 each connects the first passage portion 141 and the operating region 100. That is, each of the second branch passages 1421-1425 opens at one end to the recess 141b of the first passage portion 141 and opens at the other end to the second groove forming region 120. The passage cross-sectional area of ​​each of the second branch passages 1421-1425 may be smaller than the width D3 (see FIG. 9) of the recess 141b of the first passage portion 141.

[0098] In this way, the second passage portion 142 of the communication passage 14 is divided into a plurality of second branch passages 1421 to 1425, each having a small passage cross-sectional area. With this configuration, the glass portion 51 is less likely to infiltrate from the communication passage 14 into the operating region 100, compared to when the second passage portion 142 is configured as a single passage.

[0099] Each of the second branch passages 1421 to 1425 may extend in a serpentine manner in the in-plane direction (XY direction) of the second member 20 or in the thickness direction (Z-axis direction) of the container 2. Furthermore, each of the second branch passages 1421 to 1425 may extend in a different direction.

[0100] 17 is a schematic cross-sectional view showing an example of the configuration of a sealing unit 5 according to a fifth embodiment. As shown in FIG. 17, the sealing unit 5 may further include a shield 52.

[0101] The shield 52 is, for example, a plate-like member made of an inorganic material, and is located on a container made up of the first member 10, the second member 20, and the intermediate member 30. Specifically, the shield 52 is located on the upper surface (fifth surface) of the first member 10. The shield 52 may also be housed within the first member 10 so that it is at the same height as the first member 10. The shield 52 shields the opening of the communicating passage 14 facing the outside. To protect the glass portion 51 from the environmental conditions to which the heat dissipation device 1 is exposed, the shield 52 is preferably made of ceramic, which has excellent corrosion resistance, but chemically stable plate glass or the like may also be used.

[0102] Shield 52 may be made of ceramic, resin, or a composite thereof. Shield 52 may also contain at least one element of the glass component contained in glass portion 51. When shield 52 and glass portion 51 contain a common element, the bonding strength is improved, and therefore the bonding strength between shield 52 and glass portion 51 can be improved.

[0103] The glass portion 51 is positioned so as to close the opening of the communication passage 14 on the outside side, and joins the first member 10 and the shielding body 52 together.

[0104] In this way, the sealing portion 5 uses the glass portion 51 to fill the gap between the shield 52 that shields the communication path 14 and the first member 10. With this configuration, the hermeticity of the heat dissipation device 1 can be suitably ensured.

[0105] Sixth Embodiment Fig. 18 is a schematic cross-sectional view showing a configuration example of a sealing unit 5 according to a sixth embodiment. As shown in Fig. 18, irregularities may be formed around the opening on the surface of the container 2. Specifically, the irregularities may be formed around the opening on the upper surface (fifth surface) of the first member 10. The glass portion 51 may be located on such irregularities.

[0106] Similarly, unevenness may be formed on the surface of the shield 52 facing the first member 10 other than the portion corresponding to the opening. The unevenness formed on the surface of the container 2 and the unevenness formed on the surface of the shield 52 facing the first member 10 may fit together via the glass portion 51.

[0107] With this configuration, the contact area between glass portion 51 and container 2 is increased, improving the bonding strength between glass portion 51 and container 2. Also, the contact area between glass portion 51 and shielding body 52 is increased, improving the bonding strength between glass portion 51 and shielding body 52. ​​Also, the contact area between glass portion 51 and communicating passage 14 is reduced, making glass portion 51 less susceptible to vapor from the working fluid when heat dissipation device 1 is in use, improving corrosion resistance.

[0108] The present technology can also be configured as follows: (1) A thermal device (for example, a heat dissipation device 1) has a ceramic container (for example, a container 2), a fluid, and a sealing portion (for example, a sealing portion 5). The container has an opening located on the surface, an internal space located inside, and communication paths (for example, communication paths 14 and 15) that communicate between the opening and the internal space. The fluid is located in the internal space. The sealing portion closes the opening. The sealing portion is made of an inorganic material and has a glass portion (for example, a glass portion 51) that at least partially contains a glass component. (2) In the thermal device described in (1) above, the communication passage has a first passage portion (for example, first passage portion 141) extending in a first direction from the opening, and a second passage portion (for example, second passage portion 142) continuing from the first passage portion and opening into the internal space, and the first passage portion may have a first portion (for example, through hole 141a) including the opening, a second portion (for example, through hole 141c) continuing from the first portion and having a passage cross-sectional area different from that of the first portion, and a third portion (for example, recess 141b) continuing from the second portion and having a passage cross-sectional area different from that of the second portion. (3) In the thermal device described in (1) or (2) above, the communication passage has a first passage portion extending in a first direction from the opening, and a second passage portion continuing from the first passage portion and opening into the internal space, and the first passage portion may have a plurality of first branch passages (for example, through holes 141a). (4) In the thermal device described in any one of (1) to (3) above, the communication passage may have a first passage portion extending from the opening in a first direction and a second passage portion continuing from the first passage portion and opening into the internal space, and the second passage portion may have a fourth portion (for example, fourth portion 142c) extending in a second direction different from the first direction and a fifth portion (for example, fifth portion 142d) continuing from the fourth portion and extending in a third direction different from the second direction. (5) In the thermal device described in any one of (1) to (3) above, the communication passage may have a first passage portion extending from the opening in a first direction and a second passage portion continuing from the first passage portion and opening into the internal space, and the second passage portion may have a plurality of second branch passages (for example, second branch passages 1421 to 1425).(6) In the thermal device described in any one of (1) to (5) above, the container may contain at least one element of the glass component. (7) In the thermal device described in any one of (1) to (6) above, the glass portion may contain multiple glass components with different softening points. (8) In the thermal device described in any one of (1) to (6) above, the material of the glass portion may be crystallized glass. (9) In the thermal device described in any one of (1) to (8) above, the sealing portion may further have a shield (e.g., shield 52) made of an inorganic material located on the container and shielding the opening, and the glass portion may bond the container and the shield. (10) In the thermal device described in any one of (1) to (9) above, an unevenness may be formed on the surface of the container around the opening, and the glass portion may be located on the unevenness.

[0109] The disclosed embodiments should be considered in all respects as illustrative and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0110] REFERENCE SIGNS LIST 1 heat dissipation device 5 sealing portion 10 first member 11 first groove portion 11a first recessed portion 11b first protruding portion 14, 15 communication passage 20 second member 21 second groove portion 21a second recessed portion 21b second protruding portion 30 intermediate member 36 steam hole 37 reflux hole 51 glass portion 52 shield 100 operating region 141 first passage portion 141a through hole 141b recessed portion 141c through hole 142 second passage portion 200 frame region

Claims

1. A thermal device comprising: a ceramic container having an opening located on its surface, an internal space located inside, and a communication path connecting the opening and the internal space; a fluid located in the internal space; and a sealing part that closes the opening, wherein the sealing part is made of an inorganic material and has a glass part that contains at least a glass component.

2. A thermal device as described in claim 1, wherein the communicating passage has a first passage portion extending in a first direction from the opening, and a second passage portion continuing from the first passage portion and opening into the internal space, and the first passage portion has a first portion including the opening, a second portion continuing from the first portion and having a passage cross-sectional area different from that of the first portion, and a third portion continuing from the second portion and having a passage cross-sectional area different from that of the second portion.

3. A thermal device as described in claim 1 or 2, wherein the communication passage has a first passage portion extending in a first direction from the opening, and a second passage portion continuing from the first passage portion and opening into the internal space, and the first passage portion has a plurality of first branch passages.

4. A thermal device as described in any one of claims 1 to 3, wherein the communication passage has a first passage portion extending in a first direction from the opening, and a second passage portion continuing from the first passage portion and opening into the internal space, and the second passage portion has a fourth portion extending in a second direction different from the first direction, and a fifth portion continuing from the fourth portion and extending in a third direction different from the second direction.

5. A thermal device according to any one of claims 1 to 3, wherein the communication passage has a first passage portion extending in a first direction from the opening, and a second passage portion continuing from the first passage portion and opening into the internal space, and the second passage portion has a plurality of second branch passages.

6. A thermal device according to any one of claims 1 to 5, wherein the container contains at least one element of the glass component.

7. A thermal device according to any one of claims 1 to 6, wherein the glass portion contains a plurality of glass components with different softening points.

8. A thermal device according to any one of claims 1 to 6, wherein the material of the glass portion is crystallized glass.

9. A thermal device according to any one of claims 1 to 8, wherein the sealing portion further has a shield made of an inorganic material positioned on the container and shielding the opening, and the glass portion bonds the container and the shield.

10. A thermal device according to any one of claims 1 to 9, wherein the surface of the container has an uneven surface formed around the opening, and the glass portion is located on the uneven surface.

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