JP2006202798A - Heat sink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit heat of a heat generating body becoming an article being fixed to a heat sink and cooled more uniformly to the substrate and the heat dissipation fin side while diffusing uniformly. <P>SOLUTION: In the substrate of a base fixed with heat dissipation fins 12, a plurality of heat diffusion plates 20 for transporting heat through phase transformation of working fluid are arranged oppositely to the installation position of a plurality of heat generating bodies. Since the heat diffusion plates 20 is formed in the substrate region, heat of the heat generating bodies can be diffused to the entire region of the heat dissipation fins 12 and heat can be dissipated efficiently into the air. Consequently, heat sinks 10a-10f in which temperature rise is extremely low at the heat generating portion can be attained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat sink suitable for cooling a heating element having a high heat generation density such as a semiconductor element.

 As semiconductor elements are highly integrated and have higher outputs, losses increase and the amount of heat generated increases, so it is necessary to cool them effectively.

 Natural heat dissipation from the surface of the semiconductor element may be performed until the generation loss of the semiconductor element reaches several W level, but heat dissipation to the substrate 51 made of a good thermal conductor such as aluminum as shown in FIG. A heat sink 50 configured by attaching a large number of fins 52 is used. The heat sink 50 is coupled to the heat generating element 1 such as a semiconductor element, and heat of the heat generating element 1 is transmitted to the heat sink 50 and radiated from the heat radiation fins 52 to the atmosphere, so that the heat dissipation of the heat generating element is promoted. In addition, when the loss of a heating element such as a semiconductor element reaches a level of several tens of watts or more, it is general to further improve the heat dissipation efficiency by blowing air to the heat sink 50 by the electric fan 60. .

  As the output of the semiconductor element is further increased or the mounting density is increased, a higher heat dissipation amount per unit area is required for the heat sink. In this case, generally, as shown in FIG. 50, the interval between the comb-like heat dissipating fins 52a is made as small as possible, and the heat dissipating fins 52b are formed in a lattice shape as shown in FIG. In order to suppress the temperature rise of the semiconductor element.

In recent years, with the progress of high integration of semiconductor elements and high mounting density, if the heat dissipation amount per unit area of the heat sink exceeds 10 W / cm ² level, the heat sink as described above cannot cope with it. Further, a heat dispersion type heat sink as shown in FIG. 9 has been proposed.

  FIG. 8 shows a heat pipe 7 which is described in Patent Document 1 and is independently formed by pores 53 each sealed in a substrate 51 of a heat sink 50 having an aluminum comb-like radiating fin 52. The heat generated from the semiconductor elements 1 disposed in a dispersed manner and coupled to a part of the substrate 51 is dispersed throughout the substrate 51 by the heat pipe 7 and transmitted to the radiation fins 52. As a result, the effective heat dissipation area of the heat sink is expanded, and heat can be radiated at a low temperature difference with respect to the atmosphere.

FIG. 9 is shown in Patent Document 2 and is configured by combining the meandering capillary heat pipe 8 and the corrugated fins 53. A meandering capillary heat pipe 8 is disposed on the back surface of the substrate 51 to which the semiconductor element 1 is attached, and is joined to a plurality of corrugated fins 53. In the heat sink having such a configuration, the meandering capillary heat pipe 8 can dissipate heat from the substrate 51 by dissipating the heat to the entire corrugated fins 53 formed in multiple stages, so that effective heat dissipation of the entire heat sink can be achieved. The area can be expanded and the heat dissipation efficiency can be improved. Further, according to this heat sink, even when the generated loss varies among the plurality of semiconductor elements 1, the temperature distribution of the substrate 51 can be made uniform by the heat dispersion effect.
JP 2001-156299 A (pages 2 to 4, FIG. 1) JP 2001-223308 A (page 3-4, FIG. 1)

When cooling a heating element whose heat dissipation amount per unit area exceeds a level of 10 W / cm ² or more in response to high integration of semiconductor elements and high mounting density, the above heat is used. Although the use of a heat sink incorporating a pipe is being studied, in the case of a heat sink of the type in which the heat pipe 7 is incorporated in the heat sink substrate 51 shown in FIG. 8, a plurality of heat pipes 7 are independently formed. Therefore, since the heat distribution direction of the heat sink in the substrate 51 is limited to the longitudinal direction of the heat pipe 7, even if the effective heat dissipation area can be expanded, the variation in the heat generation distribution of the heat generating elements such as a plurality of semiconductor elements is sufficient. Can not be absorbed. In order to improve this, particularly when applied to a cooling device for a large-capacity semiconductor conversion device, it is necessary to provide a larger number of heat pipes, which increases the cost of processing the pores in the substrate 51 and the heat pipe. There's a problem.

 Further, the heat sink combining the meandering capillary heat pipe 8 and the corrugated fin 53 shown in FIG. 9 has excellent thermal diffusion performance, but performs heat transfer by vibration of the working fluid of the heat pipe in the meandering capillary. The heat transport limit value is lower than that of the conventional device shown in FIG. 8, and if the amount of heat dissipation exceeds the heat transport limit, the temperature of the heat receiving part rises rapidly, resulting in inconvenience of burning out semiconductor elements and the like.

  In addition, water cooling can be used as a heat dissipation method with high heat generation density, but when applied to electrical equipment, additional installation of electrical component insulation means, cooling water circulation system leakage prevention structure, reliability of cooling water circulation pump Redundancy for securing and installation of a heat exchanger for water and air are necessary, and there are drawbacks that result in lower reliability and higher prices than air coolers.

  As described above, in view of the problems in the conventional air-cooled and water-cooled heat sinks, the present invention eliminates the limitation of the thermal diffusion performance, and diffuses the heat of the heating element throughout the heat sink and efficiently with a low temperature difference. It is an object of the present invention to provide a heat diffusion heat sink that can dissipate heat.

  In order to solve this problem, the invention of claim 1 is characterized in that a plurality of radiating fins are implanted on one main surface of a flat substrate made of a good thermal conductor, and the object to be cooled is placed on the other main surface of the substrate. One or a plurality of heating elements are attached, and one or a plurality of heat diffusion plates for transporting heat by phase change of the working fluid are incorporated in the substrate.

 According to a second aspect of the present invention, in the heat sink according to the first aspect, an assembly hole for incorporating the heat diffusing plate into the substrate is provided directly below the heating element mounting position of the substrate, and is opened on a side surface of the substrate. It is characterized by.

 According to a third aspect of the present invention, a plurality of radiating fins are planted on one main surface of a flat substrate made of a good thermal conductor, and the heat is generated by a phase change of the working fluid by opening the other main surface in the substrate. A built-in groove or a built-in hole for incorporating one or a plurality of heat diffusion plates for transporting the heat diffusion plate is provided, and a heat diffusion plate is incorporated in the built-in groove or the built-in hole, and heat generated as a cooling medium on the heat diffusion plate The body is joined.

 According to a fourth aspect of the present invention, a plurality of radiating fins are implanted on one main surface of a flat substrate made of a good thermal conductor, and heat is transferred to the other main surface of the substrate by a phase change of the working fluid. A first board provided with a built-in groove or a built-in hole for incorporating one or a plurality of heat diffusion plates, and a second board made of a flat substrate of a good heat conductor to which a heating element to be cooled is attached And a second substrate is bonded to the other main surface of the first substrate in which the heat diffusion plate is incorporated in the assembly groove or the assembly hole.

  According to the present invention, a plurality of heat diffusion plates for transporting heat by the phase change of the working fluid are disposed inside the substrate on which the heat dissipating fins are attached, relative to the positions where the plurality of heating elements are installed. By incorporating it, the heat generated by the heating element can be diffused throughout the heat dissipation fin through this heat diffusion play, and heat can be efficiently dissipated into the atmosphere, so the temperature rise of the heat generating part is reduced. A heat sink that can be suppressed can be obtained.

 In addition, it is possible to provide a low-cost heat sink by using a pore-type heat diffusion plate that has a simple structure and can be manufactured by an extrusion method as compared with a conventional heat sink.

 Furthermore, by disposing the heat diffusion plate at a position corresponding to the mounting position of the heat generating portion, the heat of the heat generating portion can be effectively diffused and conducted to the substrate, so that the heat radiation efficiency can be improved.

  Embodiments of the present invention will be described below with reference to the embodiments shown in the drawings.

  FIG. 1 shows an entire heat sink 10a according to the present invention. A large number of heat-radiating fins 12 are integrally formed on one main surface of a substrate 11a formed in a flat plate shape by a good heat conductor such as aluminum or copper. A heating element 1 that is to be cooled, such as a semiconductor element, is coupled to one main surface that is implanted and opposed to the main surface in a required number of heats and mechanically.

  In the heat sink of the present invention configured as described above, in order to further improve the heat dissipation performance, as shown in FIGS. 1A and 1B, the heat sink is positioned immediately below the heating element 1 attached to the substrate 11a. When the heat diffusion plate 20 is incorporated in the portion of the substrate 11a to be installed, the local heat generated from the heating element 1 serving as the cooled object is diffused to the entire portion of the substrate 11a in contact with the heat diffusion plate 20. The heat is effectively radiated to the atmosphere through the heat radiation fins.

 FIG. 1A shows a state in which a heat diffusion plate 20 is incorporated in a flat substrate 11a made of a good thermal conductor. FIG. 1B shows a state in which the heat diffusion plate 20 is attached to the substrate 11a. The state which is going to insert in the built-in hole 15a opened to the side surface is shown.

 As shown in FIGS. 1A and 1B, in the heat sink 10a of the first embodiment, a plurality of radiating fins 12 are integrated with one main surface 13a of a flat substrate 11a made of a good thermal conductor at intervals. The three heating elements 1 that are to be cooled such as semiconductor elements are arranged at equal intervals on the other main surface 14a facing the main surface 13a. .

 Further, heat generated by the operation of the heating element 1 attached to the main surface of the substrate 11a is diffused and conducted more efficiently throughout the substrate 11a inside the substrate 11a, and the radiation fin 12 Assembling holes 15a are provided for inserting and incorporating the heat diffusion plate 20 for promoting heat dissipation to the atmosphere via The mounting holes 15a are provided through the substrate 11a inside the substrate 11a directly below the position where the heating elements 1 are attached, and the mounting holes 15a open on opposite side surfaces 16a.

 In addition, when assembling the thermal diffusion plate 20 in the mounting hole 15a provided in the substrate 11a, grease having high thermal conductivity is applied to the surface of the thermal diffusion plate 20 in order to maintain good thermal contact between the two. In addition, it is preferable to insert into the assembly hole 15a. For this purpose, the mounting hole 15a provided in the substrate 11a is formed to be slightly larger than the outer shape of the heat diffusion plate 20 so that the heat diffusion plate 20 coated with grease or the like can be inserted.

 Here, the structure of the heat diffusion plate is preferably a structure capable of diffusing the heat generated by the heating element 1 more efficiently over the entire contact area of the substrate 11a with the heat diffusion plate.

 As an example of the heat diffusion plate used in the present invention, a loop thermosyphon heat diffusion plate 20 in which pores 22 are provided in a substrate 21 as shown in FIGS. 4 (A), (B), and (C) is used. Is good.

 As shown in FIG. 4B, the basic configuration of the loop thermosyphon heat diffusion plate is a plurality of linear thin lines extending in the vertical direction inside a flat substrate 21 made of a good thermal conductor. A pore row in which the holes 22 are distributed in the same plane is formed.

 The upper and lower end portions of the substrate 21 form header portions 24 and 25 each comprising a groove communicating with each of the pores 22 provided over substantially the entire width of the substrate 21. All the pores 22 communicate with each other at both ends by the header portions 24 and 25. Such pores 22 constitute a sealed circulation path by sealing a two-phase condensable cooling medium on the vacuum exhaust.

 Of the pores 22 in the pore array provided inside the substrate, the sectional area of the pores (hereinafter referred to as reflux channels) located on both outer sides of the substrate 21 is larger than the sectional area of the other pores 22. Is also formed to be a reflux path 23. By forming in this way, the flow resistance in the reflux path 23 is reduced, and the two-phase condensable cooling medium 17 smoothly flows into the reflux path 23 from the pores 22 and promotes circulation of the cooling medium. Can do.

  Next, the heat transport circulation mechanism of the loop thermosyphon heat diffusion plate 20 will be described.

  In FIG. 4B, the substrate 21 is provided with pores 22 dispersed and arranged in parallel on the same plane extending in the vertical direction, and upper and lower ends thereof by header portions 24 and 25. All pores are in communication. As a result, the circulation path of the cooling medium 17 is formed as one closed loop circulation path such as the lower header portion 25-the pore 22-the upper header portion 24-the through flow passage 23-the lower header portion 25.

  When the heating element 1 attached to the lower part of the thermal diffusion plate 20 is actuated to generate heat as shown by a dotted line in FIG. 4B, the heat is generated in the lower header part 25 and the pores 22 via the substrate 21. The liquid cooling medium 17 is heated. The liquid cooling medium 17 is boiled and vaporized by heating, whereby vapor bubbles 27 are generated. The vapor bubble 27 having a density lower than that of the liquid moves upward due to its buoyancy. They are continuously generated and become a vapor flow 28, which rises through the pore array 22 upward. When the cooling medium 17 evaporates in this way, the heat of the heating element 1 is taken away by the large latent heat of vaporization and the heating element 1 is cooled.

 Since the temperature of the intermediate part and the upper part of the substrate 21 not in contact with the heating element 1 is lower than that of the part of the substrate 21 in contact with the heating element, the heat carried by the cooling medium 17 boiled and vaporized by the heating is the substrate. Heat is radiated 30 from the surface 21 to the atmosphere via the radiation fins 21, whereby the vaporized cooling medium 17 is cooled, condensed and liquefied.

 The cooling medium 17 condensed and liquefied in this way is further entrained by the vapor flow 28 and moves to the upper part of the pores 22 to become a gas-liquid two-phase flow 29 and passes through the upper header portion 24 to return to the reflux path. 23. Since the inside of the reflux path 23 is larger than the cross-sectional area of each pore 22 and the heating element 1 is not in direct contact with it, the pressure is lower than that in the pore 22. The phase flow 29 travels through the reflux path 23 and flows down to the lower header portion 25 to form a liquid pool, and again forms a boiling circulation cycle.

 In this way, a pore row composed of a plurality of pores 22 is formed inside the substrate 21, and the reflux portions 23 are provided on the upper and lower ends of the header portions 24 and 25 and the portions located on both outer sides of the substrate. The cooling medium 17 circulates in the substrate 21, and the heat locally applied by the heating element 1 is uniformly transmitted and diffused throughout the substrate 21, so that the heat dissipation efficiency of the substrate 21 can be improved.

 The mounting position of the heating element 1 serving as a cooled body such as a semiconductor element on the substrate 21 is indicated on the main surface of the substrate 21 erected in the vertical direction, as indicated by the dotted line in FIG. It is preferable that the lower portion is attached at a position that does not overlap the region of the reflux path 23. By mounting at such a position, it is possible to cause a temperature difference between the pores 22 and the reflux path 23 to generate an internal pressure difference, so that the vaporized cooling medium 17 can be smoothly refluxed.

 Although not shown, in addition to the heat diffusion plate having the structure for circulating the two-phase condensable working medium in the width direction as described above, a large number of pores extending linearly in the vertical direction in the substrate are formed. Then, after arranging it in two rows in the thickness direction of the substrate, it has grooves extending over almost the entire width of the substrate integrally bonded to the upper and lower ends of the substrate, and all the pores are formed at both ends by the groove. It is also possible to use a heat diffusion plate having a structure in which the working medium is circulated in the thickness direction, in which the two-phase condensable working medium is sealed in the sealed pores.

 However, the structure of the thermal diffusion plate 20 used in the present invention is not limited to the configuration shown in FIG. 4 or the configuration detailed in the text.

 Next, FIG. 1C shows a heat sink obtained by modifying the first embodiment.

 FIG. 1C shows the overall structure of the heat sink as in FIGS. 1A and 1B.

 As shown in FIG. 1C, in the heat sink 10b, a plurality of radiating fins 12 are integrally planted at intervals on one main surface 13b of a flat substrate 11b made of a good thermal conductor. On the other main surface 14b facing the main surface 13b, the heating element 1 serving as a cooled body such as a semiconductor element is attached.

 Further, the heat generated by the operation of the heating element 1 attached to the main surface 14b of the substrate 11b is diffused and transmitted to the substrate 11b more efficiently in the substrate 11b, and the radiating fins 12 are transmitted. One heat diffusion plate 20 for promoting heat dissipation into the air is incorporated in the three heating elements 1 in common.

 In order to incorporate this heat diffusion plate 20, a required number (1 in this embodiment) of assembling holes 15b into which the heat diffusion plate 20 can be incorporated from both side surfaces 17b opposed to the longitudinal direction of the substrate 11b. The substrate 11b is provided at a common position directly below the mounting of the individual heating elements 1.

 In addition, when assembling the thermal diffusion plate 20 into the mounting hole 15b provided in the substrate 11b, a highly thermally conductive grease or the like is applied to the surface of the thermal diffusion plate 20 in order to maintain good thermal contact between them. In addition, it is preferable to insert into the built-in hole 15b. For this purpose, the mounting hole 15b provided in the substrate 11b is formed to be slightly larger than the outer shape of the thermal diffusion plate 20 so that the thermal diffusion plate 20 coated with grease or the like can be inserted.

 It is preferable to use the heat diffusion plate 20 having the same structure as that described with reference to FIGS.

  FIG. 2 shows a second embodiment of the present invention.

 FIGS. 2A and 2B are perspective views showing a basic configuration of a heat sink 10c according to the second embodiment of the present invention.

 FIG. 2A shows a state in which the thermal diffusion plate 20 is fitted to one main surface 13c of the flat substrate 11c made of a good thermal conductor, and FIG. 2B shows an assembly groove of the substrate 11c. 15c shows a state before the heat diffusion plate 20 is assembled.

 As shown in FIGS. 2A and 2B, in the heat sink 10c of the second embodiment, a plurality of radiating fins 12 are integrated with one main surface 13c of a flat substrate 11c made of a good thermal conductor at intervals. The required number (three in this embodiment) of assembling grooves 15c for fitting and incorporating the heat diffusion plate 20 on the other main surface 14c that is implanted and faces the main surface 13c of the substrate 11c, Dispersed throughout the substrate.

 The built-in groove 15c is opened in the main surface 14c of the substrate 11c and the long side surfaces 16c. After the heat diffusion plate 20 is fitted into these, the heating element 1 is brought into contact with the heat diffusion plate 20 to thermally And mechanically coupled to each other (FIG. 2A).

 The mounting position of the heating element 1 to the heat diffusion plate 20 is the same as that in the first embodiment.

 In addition, when the thermal diffusion plate 20 is fitted in the mounting groove 15c provided in the substrate 11c, grease having high thermal conductivity or the like is applied to the surface of the thermal diffusion plate 20 in order to keep good thermal contact between the two. After application, it is preferable to fit in the mounting groove 15c. Therefore, the built-in groove 15c provided in the substrate 11c is formed slightly larger than the outer shape of the heat diffusion plate 20 so that the heat diffusion plate 20 coated with grease or the like can be fitted therein.

 It is preferable to use the heat diffusion plate 20 having the same structure as that described in the first embodiment.

 Next, FIG. 2C illustrates an example of a heat sink obtained by modifying the second embodiment.

 As shown in FIG. 2C, in the heat sink 10d, a plurality of radiating fins 12 are integrally planted at intervals on one main surface of a flat substrate 11d made of a good thermal conductor. On the other main surface opposite to the surface, a required number (one in this embodiment) of built-in grooves 15d for fitting the heat diffusion plate 20 is provided so as to cross the substrate in the longitudinal direction of the substrate 11d. It has been. After the heat diffusion plate 20 is fitted into the built-in groove 15d, the three heating elements 1 are connected in parallel on the common heat diffusion plate 20 and are thermally and mechanically coupled. (FIG. 2C).

 The mounting position of the heating element 1 to the heat diffusion plate 20 is the same as that in the first embodiment.

 In addition, when the thermal diffusion plate 20 is fitted into the mounting groove 15d provided in the substrate 11d, grease having high thermal conductivity or the like is applied to the surface of the thermal diffusion plate 20 in order to maintain good thermal contact between the two. After application, it is preferable to fit in the built-in groove 15d. Therefore, the built-in groove 15d provided in the substrate 11d is formed slightly larger than the outer shape of the heat diffusion plate 20 so that the heat diffusion plate 20 coated with grease or the like can be fitted therein.

 It is preferable to use the heat diffusion plate 20 having the same structure as that described in the first embodiment.

  3A and 3B show a third embodiment of the present invention.

 FIGS. 3A and 3B are perspective views showing a basic configuration of a heat sink 10e according to Embodiment 3 of the present invention.

 The heat sink 10e shown in FIG. 3A includes a heat diffusion plate 20 incorporated in one main surface of a flat substrate 11e made of a good thermal conductor so as to cross the substrate 11e in the short direction. 1 shows a state in which the heating element support plate 18e with 1 attached thereto is integrally coupled to the substrate 11e, and (B) is a heat sink 10e of (A), in which the substrate 11e and the base plate 13 are integrally coupled. The previous state is shown.

 In addition, since these structures of the board | substrate 11e, the radiation fin 12, and the installation groove | channel 15e of the thermal-diffusion plate 20 are the same as that of Example 2 shown in FIG. 2, they are abbreviate | omitted.

 As shown to (A) and (B) of FIG. 3A, the heat sink 10e is the board | substrate 11e in which the heat radiating fin 12 and the three heat-diffusion plates 20 were fitted, and the heat generating body 1 was attached. 11e, a flat plate-like heating element support plate 18e made of a good thermal conductor having the same area, and an upper surface of the substrate 11e to which the heat diffusion plate 20 is attached, and a support plate to which the heating element 1 is attached. The heat sink 10e is completed by joining and integrally joining the lower surface of 18e (FIG. 3A (B)).

 Here, when the substrate 11e and the support plate 18e are joined together, a grease having a high thermal conductivity is applied between them, or a thermal coupling between the two is made good by interposing them together through a row. Can do.

 In order to dissipate the heat generated from the heating element 1 more effectively by the heat diffusion plate incorporated in such an incorporation groove 15e, the mounting position of the heating element 1 on the support plate 18e is the substrate 11e and the base plate 13 Is selected at a position where the heat diffusion plate 20 hits directly under the heating element 1 ((A) of FIG. 3A).

 Moreover, it is preferable to use the thing of the structure similar to what was demonstrated in (A) and (B) of FIG.

 Next, FIGS. 3B and 3D show a heat sink obtained by modifying the third embodiment.

 As shown in (C) and (D) of FIG. 3B, the heat sink 10f has the same area as that of the substrate 11d on which the heat dissipating fins 12 and one heat diffusion plate 20 are incorporated, and the heating element 1 is attached. The upper surface of the substrate 11f to which the heat diffusing plate 20 is attached and the lower surface of the support plate 18f to which the heat generator 1 is attached are joined to each other. By combining them together, the heat sink 10f is completed (FIG. 3B (D)).

 Here, when the substrate 11f and the support plate 18f are coupled, a grease having a high thermal conductivity is applied between them, or a thermal coupling between the two is improved by interposing them together with a low interposed. Can do.

 In order to more effectively dissipate the heat generated from the three heat generating elements 1 by one heat diffusion plate 20 fitted and incorporated in such a mounting groove 15f provided in the substrate 11f, 1 is attached to the support plate 18f at a position where the heat diffusion plate 20 hits directly under the heating element 1 when the substrate 11f and the base plate 13 are thermally connected (FIG. 3B (C)). .

 Moreover, it is preferable to use the thing of the structure similar to what was demonstrated in (A) and (B) of FIG.

 In the heat sinks shown in the first to third embodiments, (A) to (C) in FIG. 1, (A) to (C) in FIG. 2, and (A) and (B) in FIG. 3A. And as shown in (C) to (D) of FIG. 3B, there are provided built-in holes or built-in grooves for assembling the thermal diffusion plate 20 between the opposing side surfaces of the substrate. It is not necessary to provide it through the opposite side surfaces of the substrate according to the heat generation conditions of the heating element 1 to be cooled such as elements, the installation environment, or the structure and shape of the heat diffusion plate, and it is also provided in the middle of both side surfaces. It may be.

 As described above, in the heat sink of the present invention in which the heat diffusing plate 20 shown in the first to third embodiments is arranged, the heat generated from the heat generating portion 1 is diffused over the entire region and radiated by the heat radiating fins. Therefore, compared with a heat sink without the heat diffusion plate 20, the heat dissipation density is reduced, and the temperature difference between the heat generating portion and the outside air is reduced, thereby significantly reducing the temperature rise of the heat generating element 1. High-density semiconductor modules can be mounted.

 In addition, it is possible to provide a low-cost heat sink by using the pore-type heat diffusion plate 20 which has a simple structure and can be manufactured by an extrusion molding method as compared with a conventional heat sink.

 Further, by disposing the heat diffusion plate at a position corresponding to the heat generating portion, necessary heat diffusion can be realized at a minimum cost.

(A) And (B) is a perspective view which shows the basic composition of the heat sink by Example 1 of this invention, (C) is a perspective view which shows the structure of the heat sink concerning other embodiment. (A) And (B) is a perspective view which shows the basic composition of the heat sink by Example 2 of this invention, (C) is a perspective view which shows the structure of the heat sink concerning other embodiment. (A) And (B) is a perspective view which shows the basic composition of the heat sink by Example 3 of this invention. (C) and (D) is a perspective view showing a configuration of a heat sink according to another embodiment of the example in FIG. 3A. It is explanatory drawing of the basic structure of the thermal diffusion plate used by this invention, (A) represents the external appearance of a heat sink, (B) is the BB sectional drawing in (A), (C) is C in (A). FIG. It is a perspective view which shows the structure of the conventional heat sink. It is a figure which shows the structure of the conventional heat sink, (A) is a top view, (B) is a side view. It is a figure which shows the structure of the conventional heat sink, (A) is a top view, (B) is a side view. It is a figure which shows the structure of the conventional heat sink, (A) is a top view, (B) is a side view. It is a figure which shows the structure of the conventional heat sink, (A) is a top view, (B) is a side view.

Explanation of symbols

1: Heating elements 10a to 10f: Heat sinks 11a to 11f: Substrate 12: Radiation fins 13a to 13f: Main surfaces 14a to 14b: Main surfaces 15a and 15b: Assembly holes 15c to 15f: Assembly grooves 16a to 16f: Side surfaces 17a to 17f : Side surfaces 18e, 18f: Heating element support plate 20: Thermal diffusion plate 21: Substrate 22: Fine pore 23: Return path 24: Upper header portion 25: Lower header portion 27: Steam bubble 28: Steam flow 28a: Liquid flow 29: Gas-liquid two-phase flow 30: heat dissipation

Claims (4)

  A plurality of heat radiation fins are planted on one main surface of a flat substrate made of a good thermal conductor, and one or more heating elements to be cooled are attached to the other main surface of the substrate, The heat sink is characterized in that it incorporates one or more heat diffusion plates that transport heat by phase change of the working fluid.  2. The heat sink according to claim 1, wherein an assembly hole for incorporating the heat diffusion plate into the substrate is provided immediately below the heating element mounting position of the substrate, and is opened on a side surface of the substrate.    A plurality of radiating fins are planted on one main surface of a flat substrate made of a good thermal conductor, and are opened to the other main surface in the substrate to transport heat by phase change of the working fluid or An assembly groove or assembly hole for incorporating a plurality of heat diffusion plates is provided, a heat diffusion plate is incorporated in the assembly groove or assembly hole, and a heating element as a cooling medium is joined on the heat diffusion plate. Heat sink characterized by. One or more heat diffusing plates are provided with a plurality of radiating fins implanted on one main surface of a flat substrate made of a good thermal conductor, and transporting heat by the phase change of the working fluid on the other main surface of the substrate. A first substrate provided with a mounting groove or a mounting hole for mounting the heat sink and a second substrate formed of a flat substrate of a good thermal conductor to which a heating element to be cooled is attached, A heat sink, characterized in that a second substrate is bonded to the other main surface of the first substrate in which the heat diffusion plate is incorporated in an assembly hole.

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