Heat dissipation substrate, vapor chamber, and functional module

Abstract

According to the present invention, a base body has a contact part with which a heat source is in contact. When a region overlapping the contact part in planar perspective is referred to as an overlapping region, a plurality of columns include two or more first columns at least partially positioned in the overlapping region, and the two or more first columns each have a long cross-sectional shape on one side. When each of a pair of first columns, adjacent to each other across a first gap, among the two or more first columns is virtually extended in the longitudinal direction, the pair of first columns have an angle on the side of the first gap in the overlapping region which intersects at a first intersection angle, and when each of a pair of first columns, adjacent to each other across a second gap different from the first gap, among the two or more first columns is virtually extended in the longitudinal direction, the pair of first columns have an angle on the side of the second gap in the overlapping region which intersects at a second intersection angle. The first intersection angle and the second intersection angle are different from each other.

Description

Heat dissipation substrate, vapor chamber and functional module

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

[0002] Japanese Patent Application Laid-Open No. 2001-339026 discloses a flat vapor chamber in which the upper and lower inner surfaces of the internal space are connected by a support pillar, which is positioned at the contact point with a heat source in a plan view.

[0003] A heat dissipation substrate according to the present disclosure comprises: a base having an internal space, an upper inner surface of the internal space, and a lower inner surface of the internal space; and a plurality of pillars located between the upper inner surface and the lower inner surface, wherein the base has a contact portion with which a heat source comes into contact, and when an area overlapping with the contact portion in a planar perspective is referred to as an overlapping area, the plurality of pillars include two or more first pillars at least a portion of which is located in the overlapping area, and each of the two or more first pillars has a cross-sectional shape that is longer in one direction, and when each of a pair of first pillars adjacent to each other across a first gap among the two or more first pillars is virtually extended in the longitudinal direction, the angle of the pair of first pillars on the side of the first gap in the overlapping area intersects at a first intersection angle, When each of a pair of adjacent first pillars among the two or more first pillars separated by a second gap different from the first gap is virtually extended in the longitudinal direction, the angle of the pair of first pillars on the second gap side in the overlapping region intersects at a second crossing angle, and the first crossing angle and the second crossing angle are different.

[0004] The vapor chamber according to the present disclosure comprises the heat dissipation substrate described above and a refrigerant located in the internal space.

[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] According to the present disclosure, a vapor chamber, a heat dissipation substrate, and a functional module with high heat dissipation performance can be provided.

[0007] 1B is a perspective view showing a vapor chamber and a heat dissipation substrate according to a first embodiment of the present disclosure; FIG. 1C is a cross-sectional view showing a vapor chamber and a heat dissipation substrate according to a first embodiment of the present disclosure; FIG. 1B is a longitudinal cross-sectional view showing a vapor chamber and a heat dissipation substrate according to a first embodiment, taken along line A-A in FIG. 1B; FIG. 1C is a longitudinal cross-sectional view showing a vapor chamber and a heat dissipation substrate according to a first embodiment, taken along line B-B in FIG. 1B; FIG. 1C is a view illustrating an arrangement of first support columns; FIG. 1D is a view illustrating an arrangement of first support columns; FIG. 1E is a view illustrating a first modified example of an arrangement of a plurality of first support columns; FIG. 1F is a view illustrating a second modified example of an arrangement of a plurality of first support columns; FIG. 1G is a view illustrating a first step of a method for virtually extending first support columns in the longitudinal direction; FIG. 1H is a view illustrating a second step of a method for virtually extending first support columns in the longitudinal direction; FIG. 1H is a view illustrating a third step of a method for virtually extending first support columns in the longitudinal direction; FIG. 1I is a view illustrating a fourth step of a method for virtually extending first support columns in the longitudinal direction; FIG. 1I is a view illustrating a first step of a method for virtually extending first support columns in the longitudinal direction. FIG. 1 is a diagram illustrating a second step of a method for virtually extending a first support column in the longitudinal direction. FIG. 2 is a diagram illustrating a third step of a method for virtually extending a first support column in the longitudinal direction. FIG. 3 is a diagram illustrating a fourth step of a method for virtually extending a first support column in the longitudinal direction. FIG. 4 is a diagram illustrating a first step of a method for virtually extending a first support column in the longitudinal direction. FIG. 5 is a diagram illustrating a second step of a method for virtually extending a first support column in the longitudinal direction. FIG. 6 is a diagram illustrating a third step of a method for virtually extending a first support column in the longitudinal direction. FIG. 7 is a diagram illustrating a fourth step of a method for virtually extending a first support column in the longitudinal direction. FIG. 8 is a cross-sectional view showing a vapor chamber and a heat dissipation substrate according to a second embodiment of the present disclosure. FIG. 9 is a cross-sectional view showing a vapor chamber and a heat dissipation substrate according to a third embodiment of the present disclosure. FIG. 10 is a longitudinal cross-sectional view of the second embodiment. FIG. 11 is a longitudinal cross-sectional view of a first modified example of the second embodiment. FIG. 12 is a longitudinal cross-sectional view of a second modified example of the second embodiment. FIG. 13 is another longitudinal cross-sectional view of the second modified example of the second embodiment. FIG. 14 is a cross-sectional view showing a vapor chamber and a heat dissipation substrate according to a fourth embodiment of the present disclosure. 10A and 10B are partial enlarged views showing a vapor chamber and a heat dissipation substrate according to a fourth embodiment of the present disclosure; FIG. 11A shows a first modified example of a cross-sectional shape of a first support pillar; FIG. 12B shows a second modified example of a cross-sectional shape of a first support pillar; and FIG. 13B shows a third modified example of a cross-sectional shape of a first support pillar.12A shows a fourth modified example of the cross-sectional shape of the first support pillar. FIG. 12B shows a fifth modified example of the cross-sectional shape of the first support pillar. FIG. 12C shows a cross-sectional view of a vapor chamber and a heat dissipation substrate according to a fifth embodiment of the present disclosure. FIG. 12D shows a cross-sectional view of a vapor chamber and a heat dissipation substrate according to a sixth embodiment of the present disclosure. FIG. 12E shows a cross-sectional view taken along line A-A in FIG. 12A. FIG. 12F shows a functional module according to a seventh embodiment of the present disclosure. FIG. 12G shows a functional module according to an eighth embodiment of the present disclosure. FIG. 12H shows a functional module according to a ninth embodiment of the present disclosure. FIG. 12H shows a functional module according to a tenth embodiment of the present disclosure. FIG. 12H shows a functional module according to an eleventh embodiment of the present disclosure.

[0008] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. Below, each part will be described by indicating the up and down directions. However, these directions may be different from the directions when the heat dissipation substrate 10 and the vapor chamber 1 are in use.

[0009] 1A and 1B are diagrams showing a vapor chamber and a heat dissipation substrate according to a first embodiment of the present disclosure, with Fig. 1A being a perspective view and Fig. 1B being a horizontal cross-sectional view. Fig. 2A is a vertical cross-sectional view taken along line A-A in Fig. 1B. Fig. 2B is a vertical cross-sectional view taken along line B-B in Fig. 1B.

[0010] The vapor chamber 1 according to the first embodiment of the present disclosure includes a heat dissipation substrate 10 having an internal space 111 and a coolant located in the internal space 111. The internal space 111 may be sealed and decompressed. The coolant is a fluid that undergoes a phase transition between a gas phase and a liquid phase, and may be water, acetone, methanol, ammonia, or the like.

[0011] The heat dissipation substrate 10 may be flat. The heat dissipation substrate 10 includes a base 11 having an internal space 111. The base 11 may have an upper inner surface 112 and a lower inner surface 113 located above and below the internal space 111, and side walls 114 that laterally surround the internal space 111. The internal space 111 may be a space that is wider horizontally than vertically. The heat dissipation substrate 10 further includes a plurality of support columns 12 located between the upper inner surface 112 and the lower inner surface 113.

[0012] The base 11 may be made of a metal such as copper or aluminum. The base 11 may be made of various materials such as ceramic, partially or entirely, for example, at the bottom surface.

[0013] A wick 115 may be located in the internal space 111. In the figure, the wick 115 is indicated by a shaded area. The wick 115 is a structure having fine voids, and may be a three-dimensional mesh structure, a porous structure formed by particles bonding together, or a structure in which multiple films with numerous pores are stacked with gaps between them. The wick 115 acts to rapidly move and diffuse the liquid refrigerant by surface tension. The wick 115 may be made of metal or various materials such as ceramic.

[0014] The base 11 has a contact portion 116 (see FIGS. 1A and 1B ) with which a heat source (i.e., a cooling target) comes into contact. FIGS. 2A and 2B show a diagram in which the heat source 41 is in contact with the contact portion 116. The contact portion 116 may be indicated in the specifications of the heat dissipation substrate 10, or may be a portion having a structure that allows easy contact with the heat source, such as a convex structure. The contact portion 116 is located on the upper surface of the base 11, but may also be located on the lower surface. The contact portion 116 may be rectangular, such as a square or rectangle, or may have various shapes, such as a circle, a polygon, or a polygon with curved sides. In a planar perspective, the area overlapping the contact portion 116 is referred to as an overlapping area 116a. Planar perspective refers to a perspective from a direction perpendicular to the upper surface of the base 11.

[0015] The plurality of support pillars 12 include two or more support pillars 12 at least partially located in the overlapping region 116a. These support pillars 12 are referred to as first support pillars 121a to 121d. In the example of FIG. 1B, the heat dissipation substrate 10 has four first support pillars 121a to 121d.

[0016] Each of the first pillars 121a to 121d has a cross-sectional shape that is long on one side. Each of the first pillars 121a to 121d may be pillars of the same shape and size from the upper inner surface 112 to the lower inner surface 113. Alternatively, the first pillars 121a to 121d may have a shape whose cross-section gradually widens as it approaches the end in the range from the upper inner surface 112 to the lower inner surface 113. The cross-sectional shapes and arrangement of the first pillars 121a to 121d will be described below, but these shapes and arrangements refer to the shapes and arrangements when the range from the upper inner surface 112 to the lower inner surface 113 is cut at the center in the vertical direction.

[0017] 3A and 3B are diagrams illustrating the arrangement of the first support columns. 3A and 3B show the same portion of the heat dissipation substrate 10. In 3A and 3B, the cross-sectional shapes of the first support columns 121a to 121d are shown without hatching in a planar perspective view.

[0018] The plurality of first pillars 121a to 121d include a pair of first pillars 121a, 121b adjacent to each other with a first gap G1 therebetween. When the pair of first pillars 121a, 121b is virtually extended in the longitudinal direction, the pair of first pillars 121a, 121b intersect at a first intersection angle θ1 on the first gap G1 side in the overlap region 116a.

[0019] Furthermore, the multiple first pillars 121a to 121d include a pair of first pillars 121b, 121c adjacent to each other with a second gap G2 therebetween. When the pair of first pillars 121b, 121c are virtually extended in the longitudinal direction, the pair of first pillars 121b, 121c intersect at a second intersection angle θ2 on the second gap G2 side in the overlap region 116a.

[0020] The first crossing angle θ1 and the second crossing angle θ2 are different from each other, and the first crossing angle θ1 is smaller than the second crossing angle θ2. The difference between the first crossing angle θ1 and the second crossing angle θ2 may be large enough to be distinguished from an error. For example, the ratio of the first crossing angle θ1 to the second crossing angle θ2 may be a value that is biased more than 2:3, such as 2:3, 1:2, or 1:3. That is, θ1 / (θ1+θ2)≦4 / 9 may be satisfied.

[0021] The difference between the first crossing angle θ1 and the second crossing angle θ2 stabilizes the flow of refrigerant in the overlap region 116a, improving the heat dissipation efficiency of the heat source. Specifically, in the first gap G1, which has a small first crossing angle θ1, the density of heat transferred through the first columns 121a and 121b is relatively high. On the other hand, in the second gap G2, which has a large second crossing angle θ2, the density of heat transferred through the first columns 121b and 121c is relatively low. Therefore, the refrigerant transitions to a gas phase more easily in the first gap G1 than in the second gap G2. Therefore, more refrigerant transitions to a gas phase in the first gap G1, and the gas-phase refrigerant tends to flow away from the first gap G1 and away from the overlap region 116a. The cooled refrigerant then transitions to a liquid phase and moves toward the overlap region 116a. Here, because of the flow of gas-phase refrigerant, the liquid-phase refrigerant is more likely to flow to the overlap region 116a through the second gap G2 than through the first gap G1. This action results in a stable refrigerant flow, with a large amount of gas-phase refrigerant being discharged from the first gap G1 and a large amount of liquid-phase refrigerant entering through the second gap G2. This stable refrigerant flow allows for high heat dissipation performance from the contact portion 116.

[0022] 3B , the multiple first columns 121a-121d further include a pair of adjacent first columns 121c, 121d sandwiching a third gap G3 therebetween, and a pair of adjacent first columns 121d, 121a sandwiching a fourth gap G4 therebetween. When the pair of first columns 121c, 121d is virtually extended in the longitudinal direction, the pair of first columns 121c, 121d intersect at a third crossing angle θ3 on the side of the third gap G3 in the overlapping region 116a. When the pair of first columns 121d, 121a is virtually extended in the longitudinal direction, the pair of first columns 121d, 121a intersect at a fourth crossing angle θ4 on the side of the fourth gap G4 in the overlapping region 116a. Similar to the first crossing angle θ1 and the second crossing angle θ2, the third crossing angle θ3 and the fourth crossing angle θ4 have a difference between them. This difference generates a stable flow of the coolant in the overlapping region 116a, as in the above-described action, and enables high heat dissipation performance from the contact portion 116.

[0023] The first columns 121a-121d may extend radially from the first portion 116b in a planar perspective. The first portion 116b corresponds to the center of the radial spread of the first columns 121a-121d. With this configuration, the refrigerant flows along the longitudinal direction of the first columns 121a-121d, creating a refrigerant flow with a radial path from the overlap region 116a. This allows the refrigerant to circulate over a large area of ​​the internal space 111, further improving heat dissipation performance.

[0024] The term "extending radially" as used above means that the longitudinal direction is oriented in the radially extending direction. The term "radially" is not limited to a strict configuration in which straight lines extending in the longitudinal direction intersect at a single point in the center, but also includes a configuration in which the spacing between the multiple first support columns 121a to 121d gradually increases from the center to the periphery. In other words, the first portion 116b may not be a single point, but may be a portion that has a spread. The above-mentioned crossing angles (i.e., the first crossing angle θ1 to the fourth crossing angle θ4) may be located at the first portion 116b.

[0025] The first pillars 121a-121d may be spaced apart from one another in the first section 116b. This space allows the above-described stable flow of coolant to occur through the first section 116b. Note that the first pillars 121a-121d are not limited to being completely spaced apart in the first section 116b. As long as there are gaps between the first pillars 121a-121d in the first section 116b that allow the coolant to flow, various structures may be employed, such as connecting one-quarter of the lower ends of the first pillars 121a-121d.

[0026] The first portion 116b may be located at the center of the overlapping region 116a in a planar perspective. This configuration provides symmetrical heat dissipation around the center of the overlapping region 116a in a planar perspective, thereby achieving higher heat dissipation performance from the contact portion 116. Being located at the center means that, in a planar perspective, any point of the first portion 116b overlaps with the center point of the overlapping region 116a. Note that, in cases where the distribution of heat applied to the contact portion 116 is not uniform, the position of the first portion 116b in a planar perspective may be shifted from the center of the overlapping region 116a depending on the heat distribution. This configuration provides heat dissipation characteristics that correspond to the heat distribution, thereby improving the heat dissipation characteristics from the contact portion 116.

[0027] <Modifications of Arrangement of First Columns> Figures 4A and 4B are diagrams illustrating modifications of the arrangement of multiple first columns. Figure 4A illustrates Modification 1, and Figure 4B illustrates Modification 2. Modification 1 in Figure 4A is an example in which two first columns 121e and 121f are provided, and a first gap G5 and a second gap G6 are located between the two first columns 121e and 121f. Even in this configuration, a difference between the first crossing angle θ5 of the first gap G5 and the second crossing angle θ6 of the second gap G6 creates a stable refrigerant flow in which a large amount of gas-phase refrigerant is discharged from the first gap G5 to the outside of the overlap region 116a and a large amount of liquid-phase refrigerant enters the overlap region 116a from the second gap G6, thereby achieving high heat dissipation performance from the contact portion 116.

[0028] 4B is an example having four first pillars 121g-121j, first to fourth gaps G7-G10 positioned between the four first pillars 121g-121j, and the first crossing angle θ7, the third crossing angle θ9, and the fourth crossing angle θ10 being smaller than the second crossing angle θ8. Even in this configuration, due to the differences in the first to fourth crossing angles θ7-θ10, a stable flow of refrigerant is generated, in which a large amount of gas-phase refrigerant is discharged from the first gap G7, the third gap G9, and the fourth gap G10 to the outside of the overlap region 116a, and a large amount of liquid-phase refrigerant enters the overlap region 116a from the second gap G8, thereby achieving high heat dissipation performance from the contact portion 116.

[0029] <Virtual extension of the first support pillar> Figures 5A to 7D are diagrams explaining the virtual outline of the first support pillar that is generated when the first support pillar is virtually extended in the longitudinal direction, with Figures 5A to 5D showing a first example, Figures 6A to 6D showing a second example, and Figures 7A to 7D showing a third example.

[0030] The virtual extension of the first support column 121b described above is performed as follows.

[0031] First, a center line A1 in the longitudinal direction of the cross section of the first support column 121b is set. If the first support column 121b is bent or curved, the center line A1 will be bent or curved (see FIGS. 5A, 6A, and 7A).

[0032] Next, the portion of the cross section of the first support column 121b that overlaps with the contact portion 116 in planar perspective is extracted (see FIGS. 5B, 6B, and 7B).

[0033] From the extracted portion, 20 percent of the center line A1 is cut off from one end in the longitudinal direction (see FIGS. 5C, 6C, and 7C). Here, 20 percent of the center line A1 refers to 20 percent of the center line A1 included in the extracted portion. This cutting is a measure to eliminate the effects of rounding at the end portions, etc. If both ends of the first support 121b in the longitudinal direction are included in the extracted portion, 20 percent is cut off from each end.

[0034] An approximate straight line is calculated from one of the remaining longitudinal sides of the outer contour. The approximate curve can be a regression line calculated using the least squares method. This approximate straight line is then used as the outer contour L1 extended from the first support 121b. Similarly, an approximate straight line is calculated from the other longitudinal side, and this approximate straight line is used as the outer contour L2 extended from the first support 121b (see FIGS. 5D, 6D, and 7D).

[0035] Of the multiple first supports 121a to 121d, the extended outlines L1 and L2 can be similarly determined for the remaining first supports 121a, 121c, and 121d. Then, the first crossing angle θ1 to the fourth crossing angle θ4 can be determined from the extended outlines L1 and L2 of the first supports 121a to 121d determined as described above.

[0036] (Embodiments 2 and 3) FIGS. 8A and 8B are cross-sectional views showing a vapor chamber and a heat dissipation substrate according to Embodiments 2 and 3 of the present disclosure. FIG. 8A is a cross-sectional view of Embodiment 2, and FIG. 8B is a cross-sectional view of Embodiment 3. In the figures, dashed arrows indicate the flow of gas-phase refrigerant, and solid arrows indicate the flow of liquid-phase refrigerant. FIG. 9A is a longitudinal cross-sectional view taken along line A-A in FIG. 8A. FIGS. 9B and 9C are longitudinal cross-sectional views taken along line A-A in FIG. 8A of Modifications 1 and 2 of Embodiment 2, respectively. FIG. 9D is a longitudinal cross-sectional view taken along line B-B in FIG. 8A of Modification 2 of Embodiment 2. FIGS. 9A to 9D show a heat source 41 in contact with contact portion 116.

[0037] The vapor chamber 1A of embodiment 2 (see FIG. 8A) differs from the vapor chamber 1A of embodiment 2 in the arrangement structure of the wick 115A of the heat dissipation substrate 10A, but is otherwise similar to embodiment 1. The heat dissipation substrate 10A of embodiment 2 has a slit 117A in the wick 115A in a partial region in a planar perspective view.

[0038] The slit 117A corresponds to a hollow portion of the internal space 111 that does not have a wick 115A, extending from the upper inner surface 112 to the lower inner surface 113.

[0039] The slit 117A is located between the first gap G1 and the third gap G3, which have a small crossing angle. The slit 117A may be located in an angular range that includes the first gap G1 and the third gap G3 and that extends from the edge of the overlapping region 116a to the side wall 114 of the internal space 111. The above angular range refers to an angular range on a horizontal plane centered on the first portion 116b.

[0040] According to the above configuration, the refrigerant that has transitioned to a gas phase in the first gap G1 and the third gap G3 can pass through the slits 117A and move quickly to the outer periphery of the internal space 111. Therefore, a fast flow of the refrigerant is achieved over a large area of ​​the internal space 111, and higher heat dissipation performance can be obtained.

[0041] A wick 115A may be positioned between the slit 117A and the first support pillar 121a-121d (corresponding to the first specific support pillar) adjacent to the slit 117A, and the slit 117A may not be in contact with the first support pillar 121a-121d. With this configuration, a large amount of liquid-phase refrigerant can be supplied via the wick 115A to the periphery of the first support pillar 121a-121d, to which a large amount of heat is transferred. This increases the amount of heat absorbed by the first support pillar 121a-121d, and further improves the heat dissipation characteristics from the contact portion 116.

[0042] The slit 117A may be positioned so as to partially overlap the overlap region 116a. A wick 115A may be positioned between the slit 117A and the side wall 114 so as to be in contact with the side wall 114. The wick 115A in contact with the side wall 114 can reduce the accumulation of liquid refrigerant on the side wall 114.

[0043] Furthermore, in the second embodiment, the slit 117A was described as a portion from the upper inner surface 112 to the lower inner surface 113 that does not have a wick 115A. This is as shown in the longitudinal cross-sectional view of FIG. 9A. However, the slit 117A may be a portion that does not have a wick 115A in a portion of the range from the upper inner surface 112 to the lower inner surface 113 of the internal space 111 (e.g., the lower half, the upper half, or an intermediate layer in the vertical direction). Even with this configuration, the rapid refrigerant flow described above can be achieved. FIG. 9B shows a vapor chamber 1A-2 and a heat dissipation substrate 10A-2 of the first modification in which the slit 117A is located in the lower half.

[0044] Furthermore, in the second embodiment, the slit 117A is not located in the center of the overlapping region 116a. This is as shown in FIGS. 9A and 9B. However, a cavity layer 118 without a wick 115A may be located in a portion (e.g., the lower half) of the overlapping region 116a extending from the upper inner surface 112 to the lower inner surface 113, and the slit 117A may be connected to the cavity layer 118. This configuration promotes the entry of liquid-phase refrigerant into the center of the overlapping region 116a while allowing the refrigerant that has transitioned to a gas phase to move more quickly out of the overlapping region 116a. This allows for improved heat dissipation performance. The cross-sectional view along line A-A in FIG. 9C and the cross-sectional view along line B-B in FIG. 9D show the vapor chamber 1A-3 and heat dissipation substrate 10A-3 of the second modification, in which the cavity layer 118 is located in the lower half of the overlapping region 116a and is connected to the slit 117A. 9C, the wick 115A located beyond the cross section can be seen. The wick 115A is indicated by thin shading.

[0045] The vapor chamber 1B of embodiment 3 (see FIG. 8B ) differs in the planar shapes of the wick 115B and the slits 117B, but is otherwise similar to embodiment 2. The heat dissipation substrate 10B of embodiment 3 has the slits 117B of the wick 115B in the first gap G1 and the third gap G3 in a planar perspective view.

[0046] The slit 117B located in the first gap G1 may have a tapered portion along the outline of the pair of first pillars 121a, 121b positioned across the first gap G1. The wick 115B located between the slit 117B and the first pillar 121a may have a substantially constant thickness. "Substantially constant" means that the thickness difference is within ±10% of the thickness. Similarly, the wick 115B located between the slit 117B and the first pillar 121b may have a substantially constant thickness. With this configuration, the amount of liquid-phase refrigerant supplied to the first pillars 121a, 121b via the wick 115B on the first gap G1 side can be made nearly uniform across the longitudinal direction of the first pillars 121a, 121b. Therefore, a nearly uniform amount of gas-phase refrigerant can be generated across the longitudinal direction of the first pillars 121a, 121b. Therefore, the amount of heat dissipated from the first support columns 121a and 121b can be improved, and the heat dissipation characteristics from the contact portion 116 can be further improved.

[0047] In the third embodiment, the slit 117B located in the third gap G3 may be similar to the slit 117B located in the first gap G1. With this configuration, the same effect as that on the first gap G1 side is achieved on the third gap G3 side.

[0048] (Embodiment 4) Figure 10A is a cross-sectional view showing a vapor chamber and a heat dissipation substrate according to embodiment 4 of the present disclosure. In the figure, dashed arrows indicate the flow of gas phase refrigerant, and solid arrows indicate the flow of liquid phase refrigerant. Figure 10B shows an enlarged view of a portion of Figure 10A. A vapor chamber 1C of embodiment 4 may have the same configuration as embodiments 1 to 3, except that the cross-sectional shapes of the multiple first support columns 121k to 121n are different.

[0049] The first pillars 121k-121n have a cross-sectional shape in which the width gradually decreases from the side closer to the first portion 116b to the side farther from the first portion 116b. This configuration makes it easier to transfer heat from the contact portion 116 to the outer periphery via the first pillars 121k-121n, and increases the area in which the wick 115 is disposed farther from the first portion 116b. This further improves the heat dissipation performance from the contact portion 116.

[0050] The shape of gradually decreasing width described above does not need to be applied to all of the first pillars 121k to 121n, but may be applied to one or more of them. Even in this configuration, the corresponding first pillars 121k to 121n can achieve the same actions and effects as described above.

[0051] The first support columns 121k-121n may have chamfered corners in their cross-sectional shapes (for example, the first corner a1 and the second corner a2 described below; see FIG. 10B). The first support column 121l corresponds to the second specific support column that contacts both the first gap G1 and the second gap G2. A chamfered shape refers to a rounded shape such as an R-shaped surface, or a shape in which a single corner has multiple vertices with large angles, such as a C-shaped surface. If the dimension along the chamfered shape from the start to the end of the chamfered shape is long, the chamfered shape is gentle, and if this dimension is short, the chamfered shape is steep.

[0052] The cross-sectional shape of the first support 121l has a first corner a1 on the first gap G1 side and a second corner a2 on the second gap G2 side at the longitudinal end portion near the first portion 116b. A small intersection angle is located at the first gap G1, and a large intersection angle is located at the second gap G2. The chamfered shape of the second corner a2 is more gradual than the chamfered shape of the first corner a1.

[0053] The cross-sectional shape of the first support 121k has a first corner a1 on the first gap G1 side and a second corner a2 on the fourth gap G4 side at the longitudinal end portion near the first portion 116b. A small intersection angle is located at the first gap G1, and a large intersection angle is located at the fourth gap G4. The chamfered shape of the second corner a2 is more gradual than the chamfered shape of the first corner a1.

[0054] The same applies to the first pillars 121m and 121n.

[0055] According to this configuration, the gently chamfered second corner a2 allows the liquid refrigerant to flow more smoothly around the second corner a2. This allows the liquid refrigerant to more smoothly enter through the second gap G2 and the fourth gap G4, where the large crossing angle is located. This further improves heat dissipation performance. Furthermore, the sharply chamfered first corner a1 increases the cross-sectional area of ​​the corners (i.e., the first corners a1) of the first columns 121k-121n that contact the first gap G1 and the third gap G3. This increases the amount of heat transferred from the first columns 121k-121n to the first gap G1 and the third gap G3. This increases the amount of heat required to transition the refrigerant to a gas phase in the first gap G1 and the third gap G3, where the small crossing angle is located. Therefore, the flow of refrigerant is enhanced, with gas phase refrigerant being discharged through the first gap G1 and the third gap G3 and liquid phase refrigerant entering through the second gap G2 and the fourth gap G4, thereby further improving the heat dissipation performance from the contact portion 116.

[0056] 11A to 11E show modified examples 1 to 5 of the cross-sectional shape of the first support pillar, respectively. In the figures, the right side indicates the side closer to the first portion 116b, the bottom side indicates the first gap G1 side where the small crossing angle is located, and the top side indicates the second gap G2 side where the large crossing angle is located.

[0057] As shown in Modification 1 of FIG. 11A, the first support column 121l may have a constant width and a chamfered shape with rounded ends at both ends in the longitudinal direction.

[0058] As shown in Modification 2 of FIG. 11B, the width of the first support column 121l may gradually decrease from near the first portion 116b to farther away, and both ends in the longitudinal direction may have a chamfered shape with rounded edges.

[0059] 11C , the first support 121l may have a constant width and a chamfered shape in which the first corner a1 and the second corner a2 are rounded. Furthermore, the second corner a2 may have a more gradual chamfered shape than the first corner a1.

[0060] 11D , the width of the first support 121l may gradually decrease from near the first portion 116b to farther away, and the first corner a1 and the second corner a2 may have a chamfered shape with rounding. Furthermore, the second corner a2 may have a more gradual chamfered shape than the first corner a1.

[0061] 11E , the width of the first support 121l may gradually decrease from near to far from the first portion 116b, the first corner a1 may have a rounded chamfered shape, and the second corner a2 may have a C-shaped chamfered shape. Furthermore, the second corner a2 may have a more gradual chamfered shape than the first corner a1.

[0062] Of the multiple first pillars 121k to 121n, the other first pillars 121k, 121m, and 121n may also have the same cross-sectional shape as those of Modifications 1 to 5. In these cases, the upper sides of Figures 11A to 11E can be interpreted as indicating the first gap G1 or third gap G3 side where the small crossing angle or crossing angle is located, and the lower sides can be interpreted as indicating the second gap G2 or fourth gap G4 side where the large crossing angle or crossing angle is located.

[0063] (Embodiments 5 and 6) Figures 12A and 12B are longitudinal cross-sectional views showing vapor chambers and heat dissipation substrates according to embodiments 5 and 6 of the present disclosure. Figure 12A shows embodiment 5, and Figure 12B shows embodiment 6. Figures 12A and 12B show a diagram in which a heat source 41 is in contact with the contact portion 116. Figure 13 shows a transverse cross-sectional view taken along line A-A in Figure 12A. Vapor chambers 1D and 1E according to embodiments 5 and 6 differ in the arrangement of the wick 115 in the overlap region 116a, but may otherwise be similar to embodiments 1 to 4.

[0064] 12A , the heat dissipation substrate 10D of the fifth embodiment has a cavity layer 119a without a wick 115 in the overlapping region 116a above the internal space 111. In the cavity layer 119a, the wick 115 may not be thin and may be in contact with the upper inner surface 112, and the upper inner surface 112 may be exposed to the cavity layer 119a.

[0065] 13, the hollow layer 119a may be the same size as the contact portion 116 in a planar perspective view, or may have a difference in size. The hollow layer 119a may have a thickness that is 10% to 50% of the vertical dimension of the internal space 111.

[0066] In the vapor chamber 1D having the cavity layer 119a, heat transferred from the contact portion 116 passes through the first support columns 121a-121d, causing much of the liquid-phase refrigerant in the wick 115 located near the sides of the first support columns 121a-121d to transition to gas phase. This action allows a large amount of heat to be absorbed from the contact portion 116 via the first support columns 121a-121d. Meanwhile, if the cavity layer 119a were not present, the refrigerant that transitioned to gas phase would accumulate within the wick 115. If this occurs, the gas-phase refrigerant would accumulate near the first support columns 121a-121d, reducing the transfer of heat from the first support columns 121a-121d to the internal space 111. Meanwhile, the presence of the cavity layer 119a allows the refrigerant that transitioned to gas phase to be sent to the cavity layer 119a, reducing accumulation within the wick 115. Therefore, the heat dissipation performance from the contact portion 116 can be improved.

[0067] 12B , heat dissipation substrate 10E of embodiment 6 has cavity layers 119a and 119b without wick 115 at the upper and lower parts of internal space 111 in overlapping region 116a. In upper cavity layer 119a, wick 115 may not be thinly positioned so as to contact upper inner surface 112, and upper inner surface 112 may be exposed to cavity layer 119a. Similarly, in lower cavity layer 119b, wick 115 may not be thinly positioned so as to contact lower inner surface 113, and lower inner surface 113 may be exposed to cavity layer 119b.

[0068] In a planar perspective view, the hollow layers 119a and 119b may be the same size as the contact portion 116, or may have a difference in size. The hollow layer 119a may have a thickness that is 10% to 50% of the vertical dimension of the internal space 111. The hollow layer 119b may have a thickness that is 10% to 50% of the vertical dimension of the internal space 111.

[0069] With the vapor chamber 1E having the hollow layers 119a and 119b, the heat transferred to the first support columns 121a to 121d causes much of the liquid-phase refrigerant in the wick 115 located near the side surfaces of the first support columns 121a to 121d to transition to gas phase, and the gas-phase refrigerant is then released into the hollow layers 119a and 119b, further reducing the accumulation of the gas-phase refrigerant in the wick 115 in the overlap region 116a. Therefore, the flow of the refrigerant is less likely to stagnate in the overlap region 116a, further improving the heat dissipation performance from the contact portion 116.

[0070] (Functional Module) Figures 14A to 15C are diagrams showing functional modules according to embodiments 7 to 11 of the present disclosure, respectively. Functional modules 400A to 400E according to embodiments 7 to 11 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 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. In Figures 14A to 15C, detailed illustrations of the internal structure of the vapor chamber 1A are omitted.

[0071] (Functional Module of Seventh Embodiment) The functional module 400A of the seventh embodiment 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.

[0072] 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 116A. The mounting portion 116A is another way of saying the contact portion 116 and corresponds to the contact portion 116.

[0073] The vapor chamber 1A has a sidewall 430 that surrounds the periphery of the mounting portion 116A of the base 11, and the mounting portion 116A 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.

[0074] According to the functional module 400A of the seventh 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.

[0075] (Functional Module of Embodiment 8) The functional module 400B of Embodiment 8 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 section 116A. 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 section 116A, 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.

[0076] 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.

[0077] According to the functional module 400B of the eighth 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.

[0078] (Functional Module of Embodiment 9) The functional module 400C of Embodiment 9 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.

[0079] 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 opposite side of the module substrate 451. Here, contact is not limited to direct contact but also includes connection via a material with high thermal conductivity (e.g., a heat transfer sheet, heat transfer grease, etc.) 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.

[0080] According to the functional module 400C of embodiment 9, a large amount of heat can be dissipated from the functional components 410C, such as LSIs and memory ICs, via the vapor chamber 1A. This allows stable computational processing by the functional components 410C. This allows for the high computing power of the LSI to be accommodated, resulting in a functional module 400C with high computing power. Furthermore, the vapor chamber 1A can dissipate heat from the functional components 410C, such as the LSIs and memory ICs, 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 LSIs and memory ICs.

[0081] (Functional Module of Embodiment 10) The functional module 400D of Embodiment 10 may be a sensor module in which an image sensor is used as a 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 116A may be located on top of the convex portion 461.

[0082] 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.

[0083] According to the functional module 400D of the tenth 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 improving the functionality of the functional module 400D.

[0084] (Functional Module of Embodiment 11) The functional module 400E of Embodiment 11 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, and the functional component 410E may be electrically connected 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.

[0085] According to the functional module 400E of the eleventh 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.

[0086] In the functional modules 400A to 400E of the seventh to eleventh embodiments, the vapor chamber 1A may be replaced with the vapor chambers 1, 1A-2, 1A-3, and 1B to 1E of the other embodiments 1, 3 to 6, and modified examples.

[0087] The above describes the embodiments of the present disclosure. However, the vapor chamber and heat dissipation substrate of the present disclosure are not limited to the above embodiments. For example, in the above embodiments, an example was shown in which the multiple first support columns located in the overlapping region 116a were all radially arranged. However, for example, the multiple first support columns located in half of the overlapping region 116a may be radially arranged on one half, and the multiple first support columns may be parallel arranged on the other half. Even with such a configuration, the same effect as in the embodiment can be achieved in half of the region.

[0088] An embodiment of the present disclosure is described below. In one embodiment, (1) a heat dissipation substrate includes: a base having an internal space, an upper inner surface of the internal space, and a lower inner surface of the internal space; and a plurality of support columns located between the upper inner surface and the lower inner surface, wherein the base has a contact portion with which a heat source comes into contact, and when a region overlapping with the contact portion in a planar perspective is referred to as an overlapping region, the plurality of support columns include two or more first support columns at least a portion of which is located in the overlapping region, and each of the two or more first support columns has a cross-sectional shape that is longer in one direction, and when each of a pair of first support columns adjacent to each other across a first gap among the two or more first support columns is virtually extended in the longitudinal direction, the angle of the pair of first support columns on the first gap side in the overlapping region intersects at a first intersection angle, and When each of a pair of adjacent first pillars among the two or more first pillars separated by a second gap different from the first gap is virtually extended in the longitudinal direction, the angle of the pair of first pillars on the second gap side in the overlapping region intersects at a second crossing angle, and the first crossing angle and the second crossing angle are different.

[0089] (2) In the heat dissipation board of (1) above, the two or more first support columns extend radially from a first portion in a planar perspective view, and the two or more first support columns are spaced apart from each other in the first portion.

[0090] (3) In the heat dissipation substrate of (2) above, the first portion is located in the center of the overlapping region in a planar perspective view.

[0091] (4) In the heat dissipation board according to any one of (1) to (3) above, the two or more first support columns extend radially in a planar perspective view.

[0092] (5) The heat dissipation substrate of any one of (1) to (4) above further comprises a wick positioned in the internal space, the first crossing angle is smaller than the second crossing angle, and a slit of the wick is positioned in the first gap.

[0093] (6) In the heat dissipation substrate of (5) above, when the pair of first pillars adjacent to each other across the first gap are referred to as a pair of first specific pillars, the wick is located between the slit and the first specific pillars.

[0094] (7) In the heat dissipation substrate of any one of (1) to (6) above, the two or more first pillars extend radially from a first portion in a planar perspective view, and at least one of the two or more first pillars has a width that gradually decreases from the side closer to the first portion to the side farther from the first portion.

[0095] (8) In any of the heat dissipation substrates (1) to (7) above, when the first support that contacts both the first gap and the second gap is called a second specific support, the cross-sectional shape of the second specific support has, at the end of the longitudinal direction on the side where the first crossing angle and the second crossing angle are located, a first corner portion located on the first gap side and a second corner portion located on the second gap side, the first crossing angle is smaller than the second crossing angle, the first corner portion has a first chamfered shape, and the second corner portion has a second chamfered shape that is gentler than the first chamfered shape.

[0096] (9) The heat dissipation substrate of any one of (1) to (8) above further comprises a wick located in the internal space, and the overlapping region includes a hollow layer in which the upper inner surface and the upper end of the wick are spaced apart.

[0097] In one embodiment, (10) a vapor chamber includes: the heat dissipation substrate according to any one of (1) to (9) above; and a coolant located in the internal space.

[0098] In one embodiment, (11) a functional module includes: a heat-generating functional component; and (10) a vapor chamber in which the functional component is mounted.

[0099] The present disclosure can be used for heat dissipation substrates, vapor chambers, and functional modules.

[0100] 1, 1A to 1E Vapor chamber 10, 10A to 10E Heat dissipation substrate 11 Base 111 Internal space 112 Upper inner surface 113 Lower inner surface 114 Side wall 115, 115A, 115B Wick 116 Contact portion 116a Overlapping region 116b First portion 117A, 117B Slit 118, 119a, 119b Cavity layer 12 Support 121a to 121n First support 121a, 121d First support (first specific support) 121l First support (second specific support) a1 First corner a2 Second corner G1, G5, G7 First gap G2, G6, G8 Second gap G3, G9 Third gap G4, G10 Fourth gap θ1, θ5, θ7 First crossing angle θ2, θ6, θ8 Second crossing angle θ3, θ9 Third crossing angle θ4, θ10 Fourth crossing angle 400A to 400E Functional modules 410A to 410E Functional parts

Claims

1. A method for manufacturing a heat exchanger comprising: a base having an internal space, an upper inner surface of the internal space, and a lower inner surface of the internal space; and a plurality of supports located between the upper inner surface and the lower inner surface, wherein the base has a contact portion with which a heat source comes into contact, and when a region overlapping with the contact portion in a plan view perspective is referred to as an overlapping region, the plurality of supports include two or more first supports at least a portion of which is located in the overlapping region, and each of the two or more first supports has a cross-sectional shape that is longer on one side, and when each of a pair of first supports adjacent to each other with a first gap between them is virtually extended in the longitudinal direction, the angle of the pair of first supports on the first gap side in the overlapping region intersects at a first intersection angle, and a heat dissipation substrate, wherein when each of a pair of adjacent first pillars among the two or more first pillars is virtually extended in the longitudinal direction, the angle of the pair of first pillars on the second gap side intersects at a second crossing angle in the overlapping region, and the first crossing angle and the second crossing angle are different.

2. The heat dissipation board according to claim 1, wherein, in a plan view, the two or more first supports extend radially from a first portion, and the two or more first supports are spaced apart in the first portion.

3. The heat dissipation board according to claim 2, wherein the first portion is located in the center of the overlapping region in a plan view.

4. A heat dissipation board according to any one of claims 1 to 3, wherein the two or more first supports extend radially in a plan view.

5. A heat dissipation substrate as described in any one of claims 1 to 4, further comprising a wick positioned in the internal space, the first crossing angle being smaller than the second crossing angle, and a slit of the wick being positioned in the first gap.

6. A heat dissipation board as described in claim 5, wherein when the pair of first pillars adjacent to each other with the first gap therebetween are referred to as a pair of first specific pillars, the wick is located between the slit and the first specific pillars.

7. A heat dissipation board as described in any one of claims 1 to 6, wherein, in a planar perspective, the two or more first supports extend radially from a first portion, and at least one of the two or more first supports has a width that gradually decreases from the side closer to the first portion to the side farther from the first portion.

8. A heat dissipation substrate as claimed in any one of claims 1 to 7, wherein when the first support that contacts both the first gap and the second gap is referred to as a second specific support, the cross-sectional shape of the second specific support has, at an end in the longitudinal direction on the side where the first crossing angle and the second crossing angle are located, a first corner located on the first gap side and a second corner located on the second gap side, the first crossing angle is smaller than the second crossing angle, the first corner has a first chamfered shape, and the second corner has a second chamfered shape that is gentler than the first chamfered shape.

9. A heat dissipation substrate as described in any one of claims 1 to 8, further comprising a wick located in the internal space, and the overlapping region includes a cavity layer separating the upper inner surface and an upper end of the wick.

10. A vapor chamber comprising: a heat dissipation substrate according to any one of claims 1 to 9; and a coolant located in the internal space.

11. A functional module comprising: a heat-generating functional component; and the vapor chamber according to claim 10 in which the functional component is mounted.

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