Heat dissipation member, vapor chamber, and functional module

Abstract

This heat dissipation member comprises: a base body having an upper wall, a first outer surface that is one surface of the upper wall, a first inner surface that is a surface on the opposite side from the first outer surface, a hollow part, and a second inner surface that faces the first inner surface with the hollow part therebetween; a wick positioned in the hollow part; and a plurality of columns positioned from the first inner surface to the second inner surface. The first outer surface has a mounting part on which a heat source is mounted. The plurality of columns include a first column that overlaps the mounting part in a plane perspective view.

Description

Heat dissipation member, vapor chamber and functional module

[0001] The present disclosure relates to a heat dissipation member, a vapor chamber, and a functional module.

[0002] Japanese Patent Application Laid-Open No. 2001-339026 discloses a structure in which a flat vapor chamber has supports that support the hollow portion.

[0003] The heat dissipation member according to the present disclosure comprises a base having an upper wall, a first outer surface which is one side of the upper wall, a first inner surface which is the surface opposite to the first outer surface, a hollow portion, and a second inner surface which faces the first inner surface across the hollow portion; a wick located in the hollow portion; and a plurality of pillars located from the first inner surface to the second inner surface, wherein the first outer surface has a mounting portion on which a heat source is mounted, and the plurality of pillars includes a first pillar which overlaps the mounting portion in a planar perspective view.

[0004] The vapor chamber according to the present disclosure comprises the heat dissipation member and a refrigerant located in the hollow portion.

[0005] The functional module according to the present disclosure comprises: a heat-generating functional component; and the vapor chamber in which the functional component is mounted.

[0006] FIG. 5A is a perspective view showing a heat dissipation member and a vapor chamber according to a first embodiment of the present disclosure. FIG. 6B is a plan view showing a heat dissipation member and a vapor chamber according to a first embodiment of the present disclosure. FIG. 7 is a diagram illustrating the overall structure of a wick. FIG. 8 is a cross-sectional view showing details of a wick. FIG. 9 is a plan view showing a heat dissipation member and a vapor chamber according to a second embodiment of the present disclosure. FIG. 10 is a rear view showing a first member of a heat dissipation member according to a second embodiment. FIG. 11 is a cross-sectional view taken along line B1-B1 of FIG. 5A. FIG. 12 is a plan view showing a second member of a heat dissipation member according to a second embodiment. FIG. 13 is a cross-sectional view taken along line B2-B2 of FIG. 14A. FIG. 15 is an enlarged view of a portion C1 of FIG. 15B. FIG. 16 is a diagram showing a functional module according to a third embodiment of the present disclosure. FIG. 17 is a diagram showing a functional module according to a fourth embodiment of the present disclosure. FIG. 18 is a diagram showing a functional module according to a fifth embodiment of the present disclosure. FIG. 19 is a diagram showing a functional module according to a sixth embodiment of the present disclosure. FIG. 20 is a diagram showing a functional module according to a seventh embodiment of the present disclosure.

[0007] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. Below, the up and down directions may be indicated when describing each part. However, these directions may be different from the directions when the heat dissipation member 10 and the vapor chamber 1 are in use.

[0008] (Embodiment 1) Figures 1A and 1B are a perspective view and a plan view showing a heat dissipation member and a vapor chamber according to embodiment 1 of the present disclosure. Figure 2 is a diagram illustrating the overall structure of the wick 13. Figure 2 is a cross-sectional view taken along line A-A in Figure 1B. The wick 13 is indicated by shading in Figures 1B and 2. Figure 3 is a cross-sectional view showing the details of the wick 13. Hatching indicating a cross section has been omitted in Figure 3.

[0009] The heat dissipation member 10 according to the first embodiment of the present disclosure includes a base 11 having a hollow portion 111 and a wick 13 located in the hollow portion 111. The wick 13 is omitted from FIG. 1A . The vapor chamber 1 according to the first embodiment of the present disclosure includes the heat dissipation member 10 and a refrigerant located in the hollow portion 111. The hollow portion 111 may be sealed and decompressed. The refrigerant is a fluid that undergoes a phase transition between a gas phase and a liquid phase, and examples of the refrigerant that may be used include water, acetone, methanol, and ammonia.

[0010] The base 11 may have a first inner surface 112 exposed to the hollow portion 111 and a second inner surface 113 exposed to the hollow portion 111 and facing the first inner surface 112. The first inner surface 112 is an inner top surface, and a mounting portion 118 on which a heat source is mounted may be located in a part of the upper portion of the base 11. The second inner surface 113 is an inner bottom surface, and the lower portion of the base 11 may be configured to be cooled. The base 11 may be flat, and in this configuration, the heat dissipation member 10 may be called a heat dissipation plate.

[0011] 2, the base 11 may have an upper wall 11a covering the upper side of the hollow portion 111, a side wall 11b covering the sides of the hollow portion 111, a lower wall 11c covering the lower side of the hollow portion 111, and a first outer surface 114 which is the outer surface of the upper wall 11a. The surface of the upper wall 11a facing the hollow portion 111 may be a first inner surface 112. A mounting portion 118 for a heat source (see FIG. 1A) may be located on the first outer surface 114.

[0012] The material of the base 11 may be a material with high thermal conductivity, for example, a metal such as copper or aluminum, or a ceramic such as silicon nitride, silicon carbide, aluminum nitride, or aluminum oxide. The base 11 may be made of a single material, or may be made of a combination of multiple types of materials, such as a bottom plate portion made of ceramic and a side wall portion and a top plate portion made of metal.

[0013] The base 11 may include a plurality of support columns 115 that support the hollow portion 111. The support columns 115 may be located across the hollow portion 111 from the first inner surface 112 to the second inner surface 113.

[0014] The wick 13 may have a plurality of minute voids G and gaps g (see FIG. 3 ) and may be configured to transport the liquid phase refrigerant by capillary force generated in the minute voids G and gaps g. The wick 13 may be positioned so as to be in contact with the first inner surface 112. The wick 13 may be positioned so as to be spaced apart from the second inner surface 113.

[0015] As shown in FIG. 1B , the hollow portion 111 may include, in a planar perspective, a region 111A where the wick 13 is located and a region 111B where the wick 13 is not located. In FIG. 1B , the regions 111A and 111B are indicated by dashed lines. The absence of the wick 13 in a planar perspective means that the wick 13 is not located between the first inner surface 112 and the second inner surface 113. As shown in FIG. 2 , in the region 111A where the wick 13 is located, a space 111c may be located between the wick 13 and the second inner surface 113. The region 111B and the space 111c may function as a passage through which the gas-phase refrigerant flows. The region 111B may not be a region where the wick 13 is not located, but may be a region where the wick 13 occupies a smaller proportion than the region 111A. For example, a configuration may be adopted in which the wick 13 is located within a range of 1 / 3 of the height of the hollow portion 111 from the first inner surface 112, and the space portion where the wick 13 is not located is larger than the region 111A. Even with this configuration, the region 111B can function as a flow path through which more gas-phase refrigerant flows than the region 111A. Alternatively, there may be no difference in the arrangement of the wick 13 between the regions 111A and 111B. In other words, the wick 13 may be located in the region 111B as well as in the region 111A. In this case, the space portion 111c functions as a flow path through which the gas-phase refrigerant easily flows.

[0016] The second inner surface 113 of the base 11 may have convex portions 113a protruding upward and concave portions 113b deepening downward. The concave portions 113b may be lattice-shaped grooves in a plan view, or stripe-shaped or radial grooves in a plan view.

[0017] As shown in FIG. 3, the wick 13 may be configured such that a plurality of particles 50 are bonded together via a portion of each particle 50. The components of each particle 50 may be a metal such as copper. Bonding between adjacent particles 50 may be achieved by a sintering process to the extent that the plurality of particles 50 do not become densified. The particle diameter of the particles 50 may be 1 μm to 1000 μm, 10 μm to 700 μm, or 20 μm to 500 μm. The particle diameter D50 of the particles 50 may be 20 μm, 100 μm, or 200 μm. The particle diameter refers to the average of the major axis and the minor axis. The particle diameter D50 refers to the median particle diameter of the particle size distribution.

[0018] Each of the plurality of particles 50 may have a first structure. The first structure is a structure in which a plurality of protrusions protrude obliquely radially from an imaginary central axis and are arranged in multiple stages along the imaginary central axis. The first structure can be formed by growing the particles 50 according to a crystal orientation in electroplating. The plurality of protrusions may include a protrusion having a maximum thickness partway from the base to the tip of the protrusion.

[0019] Alternatively, each of the multiple particles 50 may have a second structure. The second structure may have a structure in which multiple protrusions, each having a maximum thickness midway from the base to the tip, protrude in at least four different directions. The four directions may include components of three-dimensional directions. That is, when the four directions are referred to as the first to fourth directions, the four directions may be directions in which the third or fourth direction intersects with a plane along the first and second directions. The second structure can be produced, for example, by first forming multiple fine powder particles by atomization, and then sintering the multiple fine powder particles to a degree that does not cause densification of the fine powder particles. By forming nearly spherical fine powder particles by atomization, and then sintering the multiple fine powder particles together, the surrounding fine powder particles become protrusions having a maximum thickness midway from the base to the tip.

[0020] Alternatively, each of the plurality of particles 50 may be a particle 50 having a third structure. The third structure is a spherical structure. The spherical shape is not limited to a strict sphere or an oblate sphere, but includes a sphere that includes distortions or small jagged edges. The particles 50 having the third structure can be formed, for example, by an atomization method.

[0021] The wick 13 may have a structure in which the entire plurality of particles 50 is fixed by bonding portions of adjacent particles 50 together. Bonding of portions of the particles 50 together may be achieved by spreading the plurality of particles 50 in a space so that portions of the particles 50 are in contact with each other, and then performing a sintering process in this state to an extent that does not promote densification of the plurality of particles 50. When spreading the plurality of particles 50 in a space, a medium such as a resin may not be present around the plurality of particles 50, and the plurality of particles 50 may be spread in the air or a vacuum as powder.

[0022] When particles 50 having the first or second structure are used, a wick 13 can be realized in which a large number of voids G of various sizes are located between the particles 50, and small gaps g are located within each particle 50, as shown in Figure 3. This wick 13 can achieve the function of transporting a liquid-phase refrigerant by the capillary force generated in the voids G and the gaps g. When particles 50 having the third structure are used, the degree of variation in the size of the voids G, the proportion of the voids G, and the amount of the gaps g will differ, but the function of transporting a liquid-phase refrigerant by the capillary force can be similarly achieved.

[0023] The wick 13 may be fixed in the hollow portion 111 so as to contact the first inner surface 112 (see FIG. 2 ). This fixation may be achieved by bonding the first inner surface 112 to a portion of the particles 50. The bonding of the particles 50 to each other in the wick 13 and the bonding of the particles 50 to the first inner surface 112 may be achieved by the same sintering process. That is, by placing a plurality of particles 50 in the hollow portion 111 with the first inner surface 112 facing downward and performing a sintering process to an extent that does not cause the plurality of particles 50 to become densified, the bonding of the plurality of particles 50 and the bonding of the wick 13 to the first inner surface 112 can be achieved.

[0024] In the vapor chamber 1 configured as described above, for example, a heat source is located on the mounting portion 118 on the upper surface of the base 11, and a cooling portion is located on the bottom surface of the base 11. The liquid-phase refrigerant transported near the heat source on the first inner surface 112 by the capillary force of the wick 13 receives heat from the heat source via the first inner surface 112, undergoing a phase transition to a gaseous refrigerant. This phase transition absorbs a large amount of heat from the heat source. The gaseous refrigerant then flows through the void G within the wick 13, the region 111B where the wick 13 is not located, and the layer on the second inner surface 113 side of the region 111A where the wick 13 is located, using these as passages, releasing heat via the second inner surface 113, thereby transitioning to a liquid-phase refrigerant. This phase transition releases a large amount of heat to the cooling portion. By repeating the above cycle, the vapor chamber 1 can transport a large amount of heat from the heat source to the cooling portion.

[0025] (Embodiment 2) FIG. 4 is a plan view showing a heat dissipation member and a vapor chamber according to Embodiment 2 of the present disclosure. In FIG. 4, the wick 13 is indicated by shading. FIG. 5A is a rear view showing a first member of the heat dissipation member according to Embodiment 2 of the present disclosure. FIG. 5B is a cross-sectional view taken along line B1-B1 in FIG. 5A. FIG. 6A is a plan view showing a second member. FIG. 6B is a cross-sectional view taken along line B2-B2 in FIG. 6A. The heat dissipation member 10A and vapor chamber 1A according to Embodiment 2 differ in the structure of the base 11, which will be described below, and the layout of the wick 13 in a planar perspective view, but may otherwise be similar to those of Embodiment 1. In FIGS. 4 and 5A, reference numerals have been omitted from some of the multiple support columns 115 to avoid complication.

[0026] 4, the multiple support columns 115 may include a first support column 115A that overlaps with the mounting portion 118 in a planar perspective view. Even if there is a time lag between the temperature of the heat source mounted on the mounting portion 118 rising and the refrigerant in the region close to the mounting portion 118 reaching a phase transition cycle corresponding to the high temperature, the first support column 115A quickly absorbs the heat from the heat source. Therefore, it is easy to obtain a heat dissipation effect corresponding to the temperature rise of the heat source.

[0027] Furthermore, even if the temperature of the heat source rises and the internal pressure of the hollow portion 111 increases, the presence of the first support 115A can reduce deformation around the mounting portion 118 on the first outer surface 114. This stabilizes the contact state between the heat source and the heat dissipation member 10A, thereby achieving stable heat dissipation from the heat source.

[0028] Furthermore, the first support column 115A may have a larger cross-sectional area along the first outer surface 114 than the support columns 115 other than the first support column 115A. This configuration allows the first support column 115A to absorb a larger amount of heat from the heat source when the temperature of the heat source rises suddenly. This makes it easier to achieve heat dissipation in response to a sudden rise in the temperature of the heat source. Furthermore, deformation of the first outer surface 114 around the mounting portion 118 can be further reduced, allowing for more stable heat dissipation from the heat source.

[0029] In a planar perspective view, the hollow portion 111 may have a first passage R1 connected to a region 111A where the wick 13 is located, and a second passage R2 connected to a region 111B where the wick 13 is not located. In Figure 4, the regions 111A, 111B, the first passage R1, and the second passage R2 are indicated by dashed lines.

[0030] The plurality of columns 115 may include a second column 115B positioned inside the first passage R1 and a third column 115C positioned inside the second passage R2. "Positioned inside the first passage R1" means that, in a planar perspective, the column is located away from the boundary between the second passage R2 and the first passage R1 and closer to the first passage R1 than the boundary. "Positioned inside the second passage R2" means that, in a planar perspective, the column is located away from the boundary between the second passage R2 and the first passage R1 and closer to the second passage R2 than the boundary.

[0031] This configuration allows for a high degree of layout freedom in the design stage, regardless of the layout of the first passage R1 and the second passage R2. Therefore, even if there are locations where the upper wall 11a and the lower wall 11c (see FIGS. 5B and 6B ) are significantly pushed open due to an increase in internal pressure of the hollow portion 111 caused by a high temperature heat source, the support columns 115 can be placed in those locations to counteract this pushing action. Furthermore, if the internal pressure of the hollow portion 111 causes deformation of the heat dissipation member 10A evenly in the planar direction, the support columns 115 can be placed in a nearly uniform arrangement to counteract this deformation. While the example in FIG. 5A illustrates a grid-like arrangement of the support columns 115, the support columns 115 may also be arranged radially around the first support column 115A. Therefore, even if the internal pressure of the hollow portion 111 increases due to an increase in temperature of the heat source, deformation of the heat dissipation member 10A and the first outer surface 114 can be reduced. Furthermore, since deformation of the first outer surface 114 is reduced, the contact state between the heat source and the heat dissipation member 10A is stabilized, and a stable heat dissipation effect from the heat source can be obtained.

[0032] (Detailed Structure of Base 11) The base 11 may have a first member 11p1 shown in Figures 5A and 5B and a second member 11p2 shown in Figures 6A and 6B, and may be configured by joining the first member 11p1 and the second member 11p2. The first member 11p1 and the second member 11p2 may be made of a metal such as copper. Alternatively, the first member 11p1 may be made of a metal such as copper, and the second member 11p2 may be made of a ceramic such as silicon nitride, silicon carbide, aluminum nitride, or aluminum oxide.

[0033] As shown in Fig. 5B , the first member 11p1 may be a portion including the upper wall 11a, side wall 11b, and multiple support columns 115 of the base 11. As shown in Fig. 5B , the second member 11p2 may be a portion including the lower wall 11c of the base 11. Note that a portion of the side wall 11b and a portion of the support columns 115 may be included on the second member 11p2 side, rather than on the first member 11p1 side. Furthermore, the base 11 may include three or more parts including the first member 11p1 and the second member 11p2, and may be configured by joining the three or more parts.

[0034] As shown in FIG. 5A , the first member 11p1 has a bonding surface S11p1 that is bonded to the second member 11p2 around the hollow portion 111 on the back surface, and the bonding surface S11p1 may have, in a planar perspective, multiple sides j1 to j4 and multiple corners k1 to k4 that surround the hollow portion 111. The bonding surface S11p1 may also have, in a planar perspective, first bulge portions k1a to k4a that bulge inward toward the hollow portion 111 at at least one of the multiple corners k1 to k4. In the example of FIG. 5A , all four corners k1 to k4 have first bulge portions k1a to k4a. The first bulge portions k1a to k4a correspond to an example of a bulge portion of the present disclosure.

[0035] The first bulging portions k1a to k4a increase the bonding area of ​​the corners k1 to k4, which are prone to large stress when the internal pressure of the hollow portion 111 increases, and reduce deformation of the heat dissipation member 10A due to the internal pressure. Furthermore, reducing deformation of the first outer surface stabilizes the contact state between the heat source and the heat dissipation member 10A, allowing for stable heat dissipation from the heat source.

[0036] Furthermore, the joining surface S11p1 may have a second bulge portion j1a, j3a that bulges inward toward the hollow portion 111 in the middle of at least one of the multiple side portions j1 to j4. The multiple side portions j1 to j4 may include short side portions j2, j4 and long side portions j1, j3. The second bulge portion j1a, j3a may be located on the long side portions j1, j3. The second bulge portion j1a, j3a may be located on the short side portions j2, j4. The second bulge portion j1a, j3a corresponds to an example of a bulge portion of the present disclosure. The second bulge portion j1a, j3a may be located at the longitudinal center of the side portions j1, j3. Although not adopted in the configuration of FIG. 3A , the second bulge portion may be located at the longitudinal center of the side portions j2, j4.

[0037] The provision of the second bulges j1a and j3a increases the bonding area of ​​the sides j1 and j3, which are prone to large stress when the internal pressure of the hollow portion 111 increases, thereby reducing deformation of the heat dissipation member 10A due to the internal pressure. Furthermore, reducing deformation of the first outer surface stabilizes the contact state between the heat source and the heat dissipation member 10A, thereby achieving stable heat dissipation from the heat source.

[0038] 5A , the first member 11p1 may have a sealing hole 119 that leads from the outside to the hollow portion 111 or blocks the passage between the outside and the hollow portion 111. The sealing hole 119 may be a through-hole that joins the first member 11p1 and the second member 11p2 and seals the hollow portion 111 in a state where the hollow portion 111 is decompressed after injecting a refrigerant into the hollow portion 111.

[0039] In a planar perspective view, the sealing hole 119 may overlap the first bulging portions k1a to k4a or the second bulging portions j1a and j3a. Furthermore, the sealing hole 119 may communicate with the first bulging portions k1a to k4a or the second bulging portions j1a and j3a.

[0040] In the process of sealing the sealing hole 119, the periphery of the sealing hole 119 is fixed, and a relatively large force is applied to the sealing hole 119. Therefore, by positioning the sealing hole 119 as described above, it is possible to reduce deformation of the periphery of the sealing hole 119 during sealing. This stabilizes the shape of the heat dissipation member 10A after sealing the sealing hole 119. This stabilizes the contact state between the heat source and the heat dissipation member 10A, allowing for stable heat dissipation from the heat source.

[0041] The first member 11p1 may have a plurality of sealing holes 119, and the plurality of sealing holes 119 may be located at a plurality of mutually opposing locations among the plurality of first bulge portions k1a to k4a and the plurality of second bulge portions j1a, j3a. FIG. 5A shows an example in which two sealing holes 119 are located at two opposing first bulge portions k1a, k3a. However, two sealing holes 119 may be located at two opposing first bulge portions k2a, k4a, or two sealing holes 119 may be located at the second bulge portions j1a, j3a. With this configuration, in the step of sealing the sealing holes 119, the periphery of the sealing holes 119 can be stably fixed by symmetrically fixing the base 11, and the step of sealing the sealing holes 119 can be stably performed. Of the first bulging portions k1a to k4a and the second bulging portions j1a and j3a described above, bulging portions where the sealing hole 119 is not located may be omitted.

[0042] The sealing hole 119 extends in a direction intersecting the first outer surface 114, while the first member 11p1 may have a horizontal hole 120 (see FIG. 5A ) connecting the sealing hole 119 and the hollow portion 111. The horizontal hole 120 may extend in a direction along the long sides j1 and j3, or may extend in a direction along the short sides j2 and j4.

[0043] 6A and 6B, the second member 11p2 has a joining surface S11p2 whose shape matches the joining surface S11p1 of the first member 11p1, and a joining surface 113c that joins to the lower end surfaces of the multiple pillars 115. The joining of the joining surface S11p1 and the joining surface S11p2, and the joining of the lower end surfaces of the pillars 115 and the joining surface 113c may be performed by brazing.

[0044] 6C , convex portions 113a and concave portions 113b may be located in the portions of the second inner surface 113 of the second member 11p2 that are not joined to the support 115. The concave portions 113b may be arranged in a lattice shape.

[0045] (Functional Module) Figures 7A to 8C are diagrams showing functional modules according to embodiments 3 to 7 of the present disclosure, respectively. Functional modules 400A to 400E according to embodiments 3 to 7 each include a heat-generating functional component 410A to 410E and the vapor chamber 1A of embodiment 2 equipped with the functional component 410A to 410E. Specific examples of the functional modules 400A to 400E are described below, but the following structure is merely an example, and various modifications are possible to the detailed structure, etc. Detailed illustration of the internal structure of the vapor chamber 1A is omitted in Figures 7A to 8C.

[0046] (Functional Module of Embodiment 3) The functional module 400A of Embodiment 3 may be a light source module, and the functional component 410A may be a light emitting element such as an LED (Light Emitting Diode) or an LD (Laser Diode). The LD may be configured to output laser light for processing or laser light for illumination.

[0047] The functional component 410A may be mounted on the vapor chamber 1A via a submount 420. The submount 420 is a substrate smaller than the vapor chamber 1A and may be made of ceramics such as silicon nitride, silicon carbide, aluminum nitride, or aluminum oxide. Multiple functional components 410A may be mounted on the mounting portion 118.

[0048] The vapor chamber 1A has a sidewall 430 that surrounds the mounting portion 118 of the base 11, and the mounting portion 118 may be located on the inner bottom surface of a recess 431 surrounded by the sidewall 430. The opening of the recess 431 may be covered by a light-transmitting member 432 such as a lens. The light-transmitting member 432 may be bonded to the sidewall 430 to seal the recess 431. The sidewall 430 has a horizontal through-hole 433, and a conductive member 434 that transmits operating power to the functional component 410A may be bonded to the through-hole 433. A cooling mechanism (not shown) may be located below the base 11.

[0049] According to the functional module 400A of the third embodiment, a large amount of heat can be dissipated from the functional component 410A, which is a light-emitting element, via the vapor chamber 1A. Therefore, the functional component 410A, which is a light-emitting element, can stably emit light with high brightness. Furthermore, when the functional module 400A includes multiple functional components 410A, which are light-emitting elements, the high heat dissipation capability of the vapor chamber 1A can ensure uniform heat distribution among the multiple functional components 410A, thereby ensuring uniform brightness among the multiple functional components 410A.

[0050] (Functional Module of Fourth Embodiment) The functional module 400B of the fourth embodiment may be a wireless module that transmits wireless signals via a wireless base station or the like. The functional component 410B may be a signal processing circuit such as a beam forming integrated circuit (BFIC) that transmits wireless signals with directionality via an array antenna. Multiple functional components 410B may be mounted on the mounting unit 118. The functional component 410B, which is a signal processing circuit, may be connected to an antenna substrate 441 such as a phased array antenna module (PAAM) substrate on which an array antenna is mounted. That is, multiple functional components 410B may be mounted on the mounting unit 118, an antenna substrate 441 may be located above the multiple functional components 410B, and multiple antennas 441a (e.g., patch antennas) may be located above the antenna substrate 441.

[0051] The vapor chamber 1A may be located between an antenna substrate 441 and another substrate 443 located below the antenna substrate 441 via a spacer 442. Furthermore, a shield case 444 may be located below the substrate 443. The substrate 443 may have an opening 443a, and a heat dissipation component 445 such as a heat pipe embedded in the shield case 444 may extend inside and outside the shield case 444. The heat dissipation component 445 may contact the vapor chamber 1A from below via the opening 443a, and may conduct heat from the vapor chamber 1A to the outside of the shield case 444.

[0052] According to the functional module 400B of the fourth embodiment, a large amount of heat can be dissipated from the functional component 410B, which is a signal processing circuit, via the vapor chamber 1A. This allows for stable transmission of wireless signals. This contributes to increasing the power of the wireless signals, i.e., increasing the output of wireless radio waves, and reducing the module volume.

[0053] (Functional Module of Embodiment 5) The functional module 400C of Embodiment 5 may be a computer module in which a computing LSI (Large Scale Integration) is used as a functional component 410C. The functional component 410C may be an LSI for AI (Artificial Intelligence) processing, an LSI for cloud processing, an LSI for display calculation, an LSI for calculation mounted on a workstation, or any of a variety of other LSIs. In addition to the above LSI, the functional component 410C may also include a memory IC (Integrated Circuit) used by the LSI.

[0054] One or more functional components 410C may be mounted on a module substrate 451 such as a PCB (Printed Circuit Board), and the vapor chamber 1A may be incorporated so that it contacts the functional components 410C from the side opposite the module substrate 451. Here, contact is not limited to direct contact but also includes connection via a material with high thermal conductivity (such as a heat transfer sheet or thermal grease) 452. A heat dissipation component 453, such as a heat pipe 453a and a cooling fin 453b connected to the heat pipe 453a, may be connected below the base 11 of the vapor chamber 1A. Furthermore, the functional module 400C may have a cooling device 454, such as a fan, that cools the heat dissipation component 453.

[0055] According to the functional module 400C of embodiment 5, a large amount of heat can be dissipated from the functional components 410C, such as the LSI and memory IC, via the vapor chamber 1A. This allows stable computational processing by the functional components 410C. This allows the functional module 400C to accommodate the high computing power of the LSI, achieving a functional module 400C with high computing power. Furthermore, the vapor chamber 1A can dissipate heat from the functional components 410C, such as the LSI and memory IC, in response to increased heat generation due to miniaturization of wiring within the LSI, high-speed operation, and the like, as well as increased heat generation due to the three-dimensional mounting of the LSI and memory IC.

[0056] (Functional Module of Embodiment 6) The functional module 400D of Embodiment 6 may be a sensor module in which an image sensor is used as the functional component 410D. The vapor chamber 1A may have a convex portion 461 formed by a portion of the base 11 protruding, and the mounting portion 118 may be located on top of the convex portion 461.

[0057] The functional module 400D, which is a sensor module, may have a package 462 that seals the functional component 410D and a light-transmitting member 463 such as a lens. The package 462 may have an opening 464 in a portion thereof, and the vapor chamber 1A and the package 462 may be joined so that the convex portion 461 fits into the opening 464. The package 462 may have built-in wiring for transmitting electrical signals and power, and electrical signals and power may be transmitted between the functional component 410D and the outside of the package 462 via the wiring. A cooling mechanism (not shown) may be located below the vapor chamber 1A.

[0058] According to the functional module 400D of the sixth embodiment, a large amount of heat can be dissipated from the functional component 410D, which is an image sensor, via the vapor chamber 1A. Therefore, a high-performance image sensor that generates a large amount of heat and performs high-speed information processing can be applied as the functional component 410D. This contributes to the high functionality of the functional module 400D.

[0059] (Functional Module of Embodiment 7) The functional module 400E of Embodiment 7 may be a power module in which a power semiconductor for power control is used as the functional component 410E. The power semiconductor may be a switching element or a diode. The functional module 400E includes multiple vapor chambers 1A and multiple functional components 410E, and the multiple vapor chambers 1A may be mounted on a single insulating plate 471. The insulating plate 471 may be made of ceramics such as silicon nitride, silicon carbide, aluminum nitride, or aluminum oxide. A heat dissipation fin 475 may be attached to the underside of the insulating plate 471 via a metal heat dissipation plate 474. The vapor chamber 1A and the heat dissipation plate 474 may be bonded to the insulating plate 471 via a bonding material 472. The upper wall of the vapor chamber 1A may be a conductive member, and a wiring member 476 may be electrically connected to the upper wall, electrically connecting the functional component 410E so that current flows through the wiring member 476 and the upper wall. The periphery of the vapor chamber 1A, the functional component 410E, the insulating plate 471, and the heat sink 474 may be sealed with a molding material 473.

[0060] According to the functional module 400E of the seventh embodiment, a large amount of heat can be dissipated from the functional component 410E, which is a power semiconductor, via the vapor chamber 1A. Therefore, a high-output power semiconductor that generates a large amount of heat can be used as the functional component 410E, and the functional module 400E can be highly integrated and miniaturized.

[0061] The above describes each embodiment of the present disclosure. However, the heat dissipation member, vapor chamber, and functional module of the present disclosure are not limited to the above embodiments. For example, the above embodiments show a specific example of a wick formed by bonding multiple particles, but wicks of various other structures may be used. Furthermore, the above embodiments show a configuration in which the support pillar has a circular cross section, but the support pillar may have a cross section of various shapes, such as a rectangular, elliptical, or oval shape. In addition, the details shown in the embodiments can be modified as appropriate without departing from the spirit of the invention.

[0062] An embodiment of the present disclosure will be described below. In one embodiment, (1) a heat dissipation member includes: a base having an upper wall, a first outer surface that is one surface of the upper wall, a first inner surface that is the surface opposite to the first outer surface, a hollow portion, and a second inner surface that faces the first inner surface across the hollow portion, a wick located in the hollow portion, and a plurality of support columns located from the first inner surface to the second inner surface, wherein the first outer surface has a mounting portion on which a heat source is mounted, and the plurality of support columns include a first support column that overlaps the mounting portion in a planar perspective view.

[0063] (2) In the heat dissipation member of (1) above, the hollow portion has, in a planar perspective view, a first passage connecting the areas where the wick is located and a second passage connecting the areas where the wick is not located, and the plurality of supports include a second support located inside the first passage and a third support located inside the second passage.

[0064] (3) In the heat dissipation member according to (1) or (2) above, in a cross section along the first inner surface, the area of ​​the first support pillar is larger than the area of ​​the support pillars other than the first support pillar.

[0065] (4) Any one of the heat dissipation members (1) to (3) above, wherein the base has a first member including the first outer surface, the upper wall, and the first inner surface, and a second member including other parts and joined to the first member, the first member has a joining surface joined to the second member, the joining surface having, in planar perspective, a plurality of sides and a plurality of corners surrounding the hollow portion, and the joining surface having, in planar perspective, a bulge portion that bulges inward toward the hollow portion at at least one of the plurality of corners or in the middle of at least one of the plurality of sides.

[0066] (5) In the heat dissipation member of (4) above, the first member has a sealed hole that leads from the outside to the hollow portion or blocks a passage between the outside and the hollow portion, and the sealed hole overlaps with the bulge portion in a planar perspective view.

[0067] In one embodiment, (6) a vapor chamber includes: the heat dissipation member according to any one of (1) to (5); and a refrigerant located in the hollow portion.

[0068] In one embodiment, (7) the functional module includes: a heat-generating functional component; and (6) a vapor chamber in which the functional component is mounted.

[0069] The present disclosure can be used for heat dissipation members, vapor chambers, and functional modules.

[0070] 1, 1A Vapor chamber 10, 10A Heat dissipation member 11 Base 11a Upper wall 11b Side wall 11c Lower wall 11p1 First member 11p2 Second member 13 Wick 111 Hollow portion 111A Area where wick is located 111B Area where wick is not located 112 First inner surface 113 Second inner surface 113a Convex portion 113b Concave portion 113c Bonding surface with support 114 First outer surface 115 Support 115A First support 115B Second support 115C Third support 118 Mounting portion 119 Sealing hole 120 Horizontal hole 400A to 400E Functional modules 410A to 410E Functional components k1 to k4 Corner portion k1a~k4a First bulge part j1~j4 Side part j1a, j3a Second bulge part R1 First passage R2 Second passage S11p1, S11p2 Joint surface

Claims

1. A heat dissipation member comprising: a base having an upper wall, a first outer surface which is one side of the upper wall, a first inner surface which is the surface opposite the first outer surface, a hollow portion, and a second inner surface which faces the first inner surface across the hollow portion; a wick located in the hollow portion; and a plurality of support pillars located from the first inner surface to the second inner surface, wherein the first outer surface has a mounting portion on which a heat source is mounted, and the plurality of support pillars include a first support pillar which overlaps with the mounting portion in a planar perspective view.

2. A heat dissipation member as described in claim 1, wherein the hollow portion has, in a planar perspective view, a first passage connecting the areas where the wick is located and a second passage connecting the areas where the wick is not located, and the plurality of supports include a second support located inside the first passage and a third support located inside the second passage.

3. A heat dissipation member according to claim 1 or claim 2, wherein in a cross section along the first inner surface, the area of ​​the first support pillar is larger than the area of ​​the support pillars other than the first support pillar.

4. A heat dissipation member according to any one of claims 1 to 3, wherein the base has a first member including the first outer surface, the upper wall, and the first inner surface, and a second member including other portions and joined to the first member, the first member having a joining surface joined to the second member, the joining surface having, in a planar perspective, a plurality of sides and a plurality of corners surrounding the hollow portion, and the joining surface having, in a planar perspective, a bulge portion that bulges inward toward the hollow portion at at least one of the plurality of corners or midway along at least one of the plurality of sides.

5. A heat dissipation member according to claim 4, wherein the first member has a sealed hole that leads from the outside to the hollow portion or blocks a passage between the outside and the hollow portion, and the sealed hole overlaps with the bulge portion in a planar perspective view.

6. A vapor chamber comprising: a heat dissipation member according to any one of claims 1 to 5; and a refrigerant located in the hollow portion.

7. A functional module comprising: a heat-generating functional component; and the vapor chamber according to claim 6, in which the functional component is mounted.

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