JP2011258755A - Heat spreader and cooling device for heating element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat spreader excellent in thermal conductivity in a surface direction as well as in a layer direction, and to provide a cooling device for a heating element using the heat spreader.SOLUTION: A heat spreader is formed as a laminate in which a plurality of strip-shaped thermal conductivity plates 111 having better thermal conductivity in longitudinal and width directions than in the plate thickness direction are laminated in the plate thickness direction. The laminate is so configured that a surface made up by longitudinal sides 111a of the thermal conductivity plates 111 is formed as a plate surface 110a extending in a plate-like form, and a direction orthogonal to the plate surface 110a is in the thickness direction.

Description

  The present invention relates to a thermal diffuser that effectively conducts heat of a heating element such as a semiconductor element, and a heating device cooling device using the same.

  Conventionally, as a thermal diffusion body (high thermal conductivity member) for cooling a heating element, for example, as shown in Patent Document 1, a graphite structure is used instead of a metal material such as copper or aluminum. Are known. The thermal conductivity in the plane direction that is the same as the ab axis direction of the graphite structure alone exceeds 1000 W / mK, more than twice the thermal conductivity of copper (350 to 400 W / mK), and the thermal conductivity of aluminum. It has a thermal conductivity of 4 times or more (200 to 250 W / mK). However, the thermal conductivity in the layer direction (thickness direction) of the graphite structure alone is 10 W / mK or less. In order to improve this, Patent Document 1 discloses a plane parallel to the plate surface (plane direction). In addition, a structure in which a carbon structure is disposed inside a graphite structure in which the ab axes are oriented has been proposed.

  As a result, while maintaining the high thermal conductivity in the surface direction of the graphite structure as the base material, this carbon structure is also formed in the layer direction by the carbon structure composed of carbon fiber aggregates appropriately disposed inside the graphite structure. It enables efficient heat transfer through the body. As a result, it is possible to improve the laminar thermal conductivity as compared with the case of the graphite structure alone, and to contribute to increase the tensile strength and thickness of the member.

JP 2005-272164 A

  However, according to the description in Patent Document 1 (paragraph numbers 0077, 0083, 0086, 0093), the layer direction thermal conductivity is about 20 to 100 W / mK even though the layer direction thermal conductivity is improved. It is several times to 10 times the layer direction thermal conductivity (10 W / mK) of the graphite structure alone, and is still at a low level compared to metal materials such as copper and aluminum.

  In view of the above problems, an object of the present invention is to provide a thermal diffuser that is excellent in the thermal conductivity in the plane direction and also in the thermal conductivity in the layer direction and a cooling device for the heating element using the same. .

  In order to achieve the above object, the present invention employs the following technical means.

In the first aspect of the present invention, a plurality of strip-shaped thermally conductive plates (111) having better thermal conductivity in the longitudinal direction and the width direction than in the thickness direction are laminated in the thickness direction. A thermal diffusion body formed as a body,
In the laminated body, the surface formed in the laminating direction by the side (111a) in the longitudinal direction of the thermally conductive plate material (111) is formed to be a plate surface (110a) spreading in a plate shape,
It is characterized in that the direction perpendicular to the plate surface (110a) is the thickness direction.

  According to this invention, the heat conductive plate (111) constituting the heat diffuser (110) has better heat conductivity in the longitudinal direction and the width direction than the plate thickness direction, and the heat diffusion The body (110) is formed by laminating the thermally conductive plate material (111) in the plate thickness direction. Therefore, the plate surface (110a) formed in the laminating direction by the longitudinal side (111a) of the heat conductive plate (111) has good heat conductivity in the longitudinal direction of the heat conductive plate (111). Can be made. Moreover, the thickness direction orthogonal to the plate surface (110a) of the heat diffusing body (110) coincides with the width direction of the heat conductive plate (111), and thus the thickness direction of the heat diffusing body (110). Can also have good thermal conductivity. Therefore, it can be set as the thermal diffuser (110) excellent in thermal conductivity in both the plate surface (110a), that is, the surface direction, and the thickness direction, that is, the layer direction, of the thermal diffuser (110).

The invention according to claim 2 includes a plurality of the laminates,
The plurality of stacked bodies (110A, 110B) are stacked in the thickness direction and joined by an inorganic layer (112) interposed between the plurality of stacked bodies (110A, 110B),
Adjacent laminates (110A, 110B) are characterized in that the lamination directions of the heat conductive plate members (111) are different from each other.

  According to this invention, among the plurality of stacked bodies (110A, 110B), the direction of excellent thermal conductivity on the plate surface (110a) of one adjacent stacked body (110A) and the other adjacent stacked body (110B). ) In the direction of excellent thermal conductivity on the plate surface (110a). Therefore, when viewed as a whole of the thermal diffusion body (100B) in which a plurality of laminated bodies (110A, 110B) are laminated in the thickness direction, the plate surface (110a) is good not only in one direction but also in different directions. It can have a good thermal conductivity. In other words, the thermal diffuser (110) having good thermal conductivity in the two directions of the plate surface (110a) and also having good thermal conductivity in the thickness direction can be obtained.

  The invention according to claim 3 is characterized in that the angle formed by the stacking directions of the mutually different heat conductive plates (111) forms an angle of 85 to 90 degrees.

  According to the present invention, the direction of excellent thermal conductivity on the plate surface (110a) of one adjacent laminate (110A) and the thermal conductivity on the plate surface (110a) of the other adjacent laminate (110B). Since the angle formed by the excellent direction can be an angle of 85 to 90 degrees, when viewed as a whole of the thermal diffusion body (110) in which a plurality of stacked bodies (110A, 110B) are stacked in the thickness direction, In addition to giving good thermal conductivity in the thickness direction, it is possible to give good thermal conductivity in two directions substantially perpendicular to the plate surface (110a). That is, the thermal diffuser (110) having good thermal conductivity in the triaxial direction of the thermal diffuser (110) can be obtained.

  In the invention described in claim 4, the inorganic layer (112) includes at least one of titanium (Ti), nickel (Ni), tin (Sn), lead (Pb), and gold (Au). It is characterized by being a layer.

  According to the present invention, when a thermal diffusion body (110) is formed by laminating a plurality of laminated bodies (110A, 110B) and joining them with an inorganic layer (112), the thermal conductivity and electrical conductivity are improved. It can be set as the joining layer which is excellent and is excellent in bondability.

In the invention according to claim 5, a plurality of the laminates are arranged in the direction in which the plate surface (110a) expands, and a part of each plate surface (110a) of the plurality of laminates is a heating element (120). Is included in the connection area for connecting
In each laminate,
The longitudinal direction of the heat conductive plate (111) of each laminate is
Any one point (A) in the connection area;
Among the outer peripheral portions of each laminate, the laminates are arranged so as to be parallel to an imaginary line connecting an arbitrary point (B) on the outer peripheral portion included in the entire outer peripheral portion formed by a plurality of laminates. It is characterized by that.

  According to this invention, in each laminated body, a thermally conductive plate material (parallel to an imaginary line from an arbitrary point (A) in the connection region to an arbitrary point (B) on the outer peripheral portion ( 111) is set in the longitudinal direction, it is possible to provide good thermal conductivity in the direction parallel to the virtual line on the plate surface (110a) and in the thickness direction. Furthermore, in the thermal diffuser (110) formed by a plurality of laminated bodies, the direction extending from the arbitrary point (A) in the connection region toward the outer peripheral portion of the thermal diffuser (110), and the thickness direction Can have good thermal conductivity. That is, when the heating element (120) is connected to the thermal diffusion body (110), the thickness of the heating element (120) is increased so as to spread from the connection region toward the outer periphery of the thermal diffusion body (110). It can be set as the thermal diffusion body (110) which can be made to conduct favorably in the vertical direction.

In the invention according to claim 6, the plurality of laminates are composed of four laminates (110C to 110F) in which the plate surface (110a) forms a square shape,
One corner of each laminated body (110C to 110F) is included in the connection region.

  According to the present invention, a highly feasible thermal diffuser (110) can be easily formed without wasting material.

  The invention according to claim 7 is characterized in that the thermal conductivity in the thickness direction of the laminate is 600 W / mK or more.

  According to this invention, it can be set as the thermal-diffusion body (110) which enables the utilization in the wide field | area which requires favorable heat conduction.

  The invention according to claim 8 is characterized in that the thermally conductive plate (111) is a graphite material or a composite material of graphite and metal.

  According to the present invention, the graphite material or the composite material of graphite and metal has better thermal conductivity than a commonly used copper material or aluminum material. An excellent thermal diffuser (110) can be realized.

In invention of Claim 9, in a cooling device, the thermal-diffusion body (110) as described in any one of Claims 1-8,
A heating element (120) disposed on one plate surface (110a) of the thermal diffusion body (110);
An insulating plate (130) disposed on the other plate surface (110a) of the thermal diffusion body (110);
It is characterized by comprising a cooler (140) disposed on the surface of the insulating plate (130) opposite to the heat diffusion body (110).

  According to the present invention, it is possible to effectively cool the heating element (120) using the thermal diffusion body (100) having good thermal conductivity in the plate surface (110a) and the thickness direction.

In invention of Claim 10, a heat generating body (120) is a semiconductor element (120),
A metal plate (150) is disposed between the thermal diffuser (110) and the insulating plate (130).

  According to this invention, the insulating plate (130) prevents the leakage to the cooler (140) side, and the metal plate (150) can be used as a power extraction part of the semiconductor element (120).

In invention of Claim 11, a heat generating body (120) is a semiconductor element (120),
A metal plate (150) is disposed between the heating element (120) and the thermal diffusion body (110).

  According to the present invention, since the semiconductor element (120) and the metal plate (150) can be brought into direct contact with each other, when the semiconductor element (120) uses a large current, it is described in claim 10. Compared with the present invention, the metal plate (150) can be used as a power extraction portion of the semiconductor element (120) without receiving an electrical resistance due to the thermal diffuser (110).

In invention of Claim 12, in a cooling device, it is a thermal diffusion body (110) of Claim 3, Comprising: Thermal diffusion body (110) provided with two laminated bodies,
A heating element (120) disposed on one plate surface (110a) of the thermal diffusion body (110);
An insulating plate (130) disposed on the other plate surface (110a) of the thermal diffusion body (110);
A cooler (140) disposed on the surface of the insulating plate (130) opposite to the thermal diffuser (110);
Of the two laminates (110A, 110B) in the thermal diffusion body (110), the dimension in the thickness direction of one laminate (110A) is t1, and the dimension in the thickness direction of the other laminate (110B) is t2. age,
In the longitudinal direction of the heat conductive plate (111) of one laminate (110A), the distance from the center position of the heating element (120) to the end of the thermal diffuser (110) is r1, and the other laminate (110B). When the distance from the center position of the heating element (120) to the end of the thermal diffusion body (110) in the longitudinal direction of the thermal conductive plate (111) is r2,
Between the dimensions t1, t2 and the distances r1, r2,
0.5 ≦ (t1 / t2) / (r1 / r2) ≦ 2
It is characterized by the fact that this relationship is established.

  According to this invention, it can be said that in one laminated body (110A), it is preferable to conduct the heat of the heating element (120) to the distance r1 side as the distance r1 is larger. Similarly, in the other laminate (110B), it can be said that it is preferable to conduct the heat of the heating element (120) to the distance r2 side as the distance r2 is larger. And the dimension of the thickness direction of each laminated body (110A, 110B) should be thickened or thinned according to the magnitude of the heat conducted. That is, if the distance r1 (r2) is large, the dimension t1 (t2) can be increased. Conversely, if the distance r1 (r2) is small, the dimension t1 (t2) needs to be decreased. Therefore, considering good heat conduction in the thermal diffuser (110), it is theoretically preferable to set (r1 / r2) and (t1 / t2) to the same value, (t1 / t2) / ( That is, r1 / r2) = 1 is preferable. With respect to this theoretical value 1, practically, heat conduction in the range of 0.5 to 2.0 provides good heat conduction in the heat diffusing body (110), and a good heating element (120 ) Can be cooled.

In the invention according to claim 13, in the method for manufacturing a thermal diffuser, a plate-like thermally conductive plate material (111) having better thermal conductivity in the plane direction than in the plate thickness direction is provided in the plate thickness direction. By laminating a plurality, a laminate is formed,
The laminate is cut into a plate shape in the laminating direction along one side (111b) of the thermally conductive plate material (111) to form a plate-like body,
In the plate-like body, the surface formed in the laminating direction by one side (111b) of the thermally conductive plate material (111) is a plate surface (110a) spreading in a plate shape,
The thickness direction is a direction orthogonal to the plate surface (110a).

  According to this invention, it can provide as a method of manufacturing the thermal diffusion body (110) according to claim 1.

In the invention according to claim 14, in the method of manufacturing a thermal diffuser, a plate-like thermally conductive plate material (111) having better thermal conductivity in the plane direction than in the plate thickness direction is provided in the plate thickness direction. By laminating a plurality, a laminate is formed,
The laminated body is cut into a plate shape in the laminating direction along one side (111b) of the thermally conductive plate material (111) to form a primary plate-like body,
In the primary plate-like body, the surface formed in the laminating direction by one side (111b) of the thermally conductive plate material (111) is a plate surface (110a) extending in a plate shape,
The direction orthogonal to the plate surface (110a) is the thickness direction,
A quadrilateral shape is formed by cutting off the four corners of the primary plate-like body, and the direction of one side (111b) of the thermally conductive plate material (111) is oblique with respect to each side of the square shape formed by the cut-off. Forming a secondary plate-like body,
Prepare a plurality of secondary plates,
A plurality of secondary plate-like bodies are arranged in the direction in which the plate surface (110b) expands, and a part of each plate surface (110a) is included in the connection region for connecting the heating element (120). And
In each secondary plate,
The direction of one side (111b) of the thermally conductive plate (111) of each secondary plate is
Any one point (A) in the connection area;
Parallel to an imaginary line connecting an arbitrary point (B) on the outer peripheral portion included in the entire outer peripheral portion formed by the plurality of secondary plate-like bodies among the outer peripheral portions of the respective secondary plate-like bodies. It arrange | positions so that it may become.

  According to this invention, it can provide as a method of manufacturing the thermal diffusion body (110) according to claim 5.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows a corresponding relationship with the specific means of embodiment description mentioned later.

It is a disassembled perspective view which shows the cooling device of the heat generating body in 1st Embodiment. It is a perspective view which shows the thermal diffusion body in FIG. It is a perspective view which shows the manufacturing method of the thermal-diffusion body in 2nd Embodiment. It is a disassembled perspective view which shows the cooling device of the heat generating body in 3rd Embodiment. It is a perspective view which shows the manufacturing method of the thermal diffusion body in FIG. It is a graph which shows the thickness direction heat conductivity of the thermal diffusion body in FIG. It is a disassembled perspective view which shows the cooling device of the heat generating body in 4th Embodiment. It is a disassembled perspective view which shows the cooling device of the heat generating body in 5th Embodiment. It is a disassembled perspective view which shows the cooling device of the heat generating body in 6th Embodiment. It is a disassembled perspective view which shows the cooling device of the heat generating body in 7th Embodiment. It is a perspective view which shows the thermal diffusion body in FIG. It is a perspective view which shows the manufacturing method of the thermal diffusion body in FIG.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly indicate that the combination is possible in each embodiment, but also a combination of the embodiments even if they are not clearly specified unless there is a problem with the combination. It is also possible.

(First embodiment)
Hereinafter, the cooling device 100 </ b> A of the heating element in the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is an exploded perspective view showing a cooling device 100A for a heating element, and FIG. 2 is a perspective view showing a heat diffusing body 110 in FIG.

  As shown in FIG. 1, a cooling device (hereinafter referred to as a cooling device) 100A for a heating element includes a thermal diffuser 110, a heating element 120, an insulating plate 130, and a cooler 140, and heats the heating element 120. The heat generator 120 is cooled by being conducted to the cooler 140 by the diffuser 110.

  As shown in FIG. 2, the thermal diffuser 110 is a plate that efficiently conducts the heat of the heating element 120 to the cooler 140 side, and is formed of a plurality of thermally conductive plates 111. The thermally conductive plate material 111 is an extremely thin plate member having a strip shape, and has better thermal conductivity in the longitudinal direction and the width direction than in the plate thickness direction. The heat conductive plate 111 is formed using, for example, a graphite material or a composite material of graphite and metal. As the metal in the case of the composite material, for example, copper or aluminum is used. In particular, in the graphite material, as described above, a highly oriented graphite material having excellent thermal conductivity in the thickness direction and width direction of the thermally conductive plate material 111, that is, in the two directions of the plate surface, is used.

  A plurality of the heat conductive plate materials 111 are stacked in the plate thickness direction to form a plate-shaped stacked body. In the first embodiment, the stacked body is the heat diffusing body 110. That is, in this laminated body, a plate surface 110a extending in a plate shape in the stacking direction is formed by the long side 111a in the longitudinal direction of the heat conductive plate material 111, and the direction orthogonal to the plate surface 110a is a plate shape. This is the thickness direction of the laminate. The heat diffusing body 110 has a plate shape in which the dimension in the stacking direction is larger than the dimension in the width direction of the heat conductive plate 111. In other words, the plate surface 110a is a surface surrounded by the long side 111a and the side formed in the stacking direction. The dimension in the thickness direction of the heat diffusing body 110 is equal to the dimension in the width direction of the heat conductive plate 111. Therefore, the thermal diffuser 110 has excellent thermal conductivity in the two directions of the long side 111a and the thickness direction on the plate surface 110a.

  Note that the thermal diffuser 110 is a material formed by laminating a plurality of thermally conductive plates 111 after being laminated, or in a gaseous state (highly oriented graphite material or composite material of highly oriented graphite and metal). Are sequentially sprayed on a flat surface to form a laminate.

  The heating element 120 is a semiconductor element that generates heat when an IGBT (insulated gate bipolar transistor), FWD (flywheel diode), or the like is operated, and a plurality of heating elements 120 (here, abutting against one plate surface 110a of the thermal diffusion body 110) There are two).

  The insulating plate 130 is a plate member for insulation with respect to the heating element 120 formed of, for example, a ceramic material, and the other plate surface 110a of the heat diffusing body 110 (on the side opposite to the plate surface 110a on which the heating element 120 is provided). Surface).

  The cooler 140 is a heat exchanger that cools the heating element 120 by moving the heat of the heating element 120 to a cooling medium that circulates in the internal passage 142, and is opposite to the heat diffusion body 110 of the insulating plate 130. It is provided so that it may contact | abut. The cooler 140 is formed by providing a large number of passages 142 inside a plate-shaped main body 141. A cooling medium (for example, cooling air or cooling water) is circulated through the passage 142.

  In the cooling device 100A configured as described above, the heat of the heating element 120 spreads to the outer peripheral side along the plate surface 110a (the direction of the long side 111a) of the thermal diffusion body 110, and in the thickness direction. Conducted towards. This heat is further conducted in the thickness direction of the insulating plate 130 and reaches the main body 141 of the cooler 140. In the cooler 140, the heat of the heating element 120 conducted as described above is transferred to the cooling medium flowing through the internal passage 142, and the heating element 120 is cooled.

  In the present embodiment, the thermally conductive plate 111 constituting the thermal diffuser 110 has better thermal conductivity in the longitudinal direction and the width direction than the thickness direction of the thermal diffuser 110. The heat conductive plate 111 is formed by being laminated in the plate thickness direction. Therefore, the plate surface 110a formed in the stacking direction by the longitudinal sides 111a of the heat conductive plate 111 can have good heat conductivity in the length direction of the heat conductive plate 111. Moreover, the thickness direction orthogonal to the plate surface 110a of the heat diffusing body 110 coincides with the width direction of the heat conductive plate 111, and the heat diffusing body 110 also has good heat conductivity. Can be made. Therefore, the heat diffuser 110 having excellent thermal conductivity in both the plate surface 110a, that is, the surface direction and the thickness direction, that is, the layer direction, of the heat diffuser 110 can be obtained, and the heat of the heating element 120 is transferred to the cooler 140. It is possible to conduct efficiently toward.

(Second Embodiment)
FIG. 3 shows a thermal diffuser 110 (a manufacturing process of the thermal diffuser 110) according to the second embodiment. 2nd Embodiment changes the manufacturing method of the thermal-diffusion body 110 with respect to the said 1st Embodiment (FIG. 1, FIG. 2).

  Hereafter, the manufacturing method is demonstrated in order. First, a plate-like heat conductive plate 111 having better heat conductivity in the plane direction than in the plate thickness direction is prepared (FIG. 3A), and a plurality of the heat conductive plate materials 111 are stacked in the plate thickness direction. Thus, a laminated body is formed (FIG. 3B).

  Next, the laminated body formed as described above is cut along the one side 111b of the thermally conductive plate material 111 in the lamination direction to form a plate-like body (FIG. 3C). In this plate-like body, a surface formed in the laminating direction by one side 111b of the heat conductive plate 111 is a plate surface 110a, and a direction perpendicular to the plate surface 110a is a thickness direction. (FIG. 3D).

  Thereby, the thermal diffusion body 110 equivalent to the thermal diffusion body 110 demonstrated in the said 1st Embodiment can be formed easily.

(Third embodiment)
A cooling device 100B of the third embodiment is shown in FIGS. In the third embodiment, the thermal diffuser 110 is formed from a plurality of thermal diffusers 110A and 110B as compared to the first embodiment (FIGS. 1 and 2).

  As shown in FIGS. 4 and 5, the thermal diffuser 110 is an embodiment using two thermal diffusers (laminates), and includes a first thermal diffuser 110A and a second thermal diffuser 110B. Yes. Each of the thermal diffusion bodies 110A and 110B is the same as that described in the first embodiment, but in the usage pattern, the stacking directions of the thermally conductive plate materials 111 are different from each other.

  That is, in the first heat diffusion body 110A, the stacking direction of the heat conductive plate members 111 is the depth direction in FIG. Therefore, in the first thermal diffuser 110A, thermal conductivity is excellent in the left-right direction (longitudinal direction of the thermally conductive plate 111) and the thickness direction on the plate surface 110a in FIG.

  On the other hand, in the second thermal diffuser 110B, the stacking direction of the heat conductive plate 111 is the left-right direction in FIG. Therefore, in the 2nd heat diffusion body 110B, thermal conductivity is excellent in the depth direction (longitudinal direction of the heat conductive board | plate material 111) in the board surface 110a in FIG. 5, and the thickness direction.

  The first heat diffuser 110A and the second heat diffuser 110B are stacked in the thickness direction and joined by an inorganic bonding layer 112 interposed between the heat diffusers 110A and 110B. The bonding layer 112 can be formed as a layer including at least one of titanium (Ti), nickel (Ni), tin (Sn), lead (Pb), and gold (Au). Here, solder containing tin (Sn) is used as the bonding layer 112. The thermal conductivity of the solder is 60 W / mK.

  The heat diffusion body 110 formed as described above has a shape in which the stacking directions intersect with each other in the first heat diffusion body 110A and the second heat diffusion body 110B because the stacking directions of the heat conductive plate members 111 are different. It has become. Specifically, the angle formed by the lamination direction of both is approximately 90 degrees. The angle formed by the stacking direction is preferably 85 to 90 degrees in order to provide good thermal conductivity in the biaxial direction on the plate surface 110a.

  In the thermal diffuser 110 of this embodiment, the direction in which the thermal conductivity on the plate surface 110a of the first thermal diffuser 110A is excellent and the direction in which the thermal conductivity on the plate surface 110a of the second thermal diffuser 110B is excellent are formed. Since the angle can be an angle of 85 to 90 degrees, in addition to the thickness direction, when viewed as a whole of the thermal diffusion body 110 in which a plurality of thermal diffusion bodies 110A, 110B are stacked in the thickness direction, In the plate surface 110a, good thermal conductivity can be given in two substantially orthogonal directions. Therefore, the heat diffusing body 110 having excellent thermal conductivity in the triaxial direction can be obtained, and the heating element 120 can be efficiently cooled.

  FIG. 6 is a graph showing the thermal conductivity in the thickness direction of the thermal diffuser 110 formed by the plural thermal diffusers 110A and 110B with respect to the thermal conductivity of the bonding layer 112. As one model of the present embodiment, the length of each thermal diffuser 110A, 110B is 32 mm, the width is 18 mm, the thickness is 1 mm, and the thickness of the bonding layer 112 is 0.1 mm. The thermal conductivity in the thickness direction was examined. A thermal conductivity of 600 W / mK in the thickness direction of the thermal diffuser 110 could be obtained at a thermal conductivity of 60 W / mK of the bonding layer 112 (solder). This value is much larger than the thermal conductivity of copper and aluminum.

  In the above embodiment, the thermal diffuser 110 is formed from the two thermal diffusers 110A and 110B. However, the thermal diffuser 110 may be formed by stacking three or more thermal diffusers. In this case, among the three or more thermal diffusers, in the adjacent thermal diffusers, the direction excellent in thermal conductivity is different from the direction (more preferably, the angle formed by the direction excellent in thermal conductivity is 85 to 90 degrees). Good.

(Fourth embodiment)
A cooling device 100C of the fourth embodiment is shown in FIG. In the fourth embodiment, a metal plate 150 is added to the third embodiment (FIG. 4).

  The metal plate 150 is, for example, a copper or aluminum plate having excellent conductivity, and is interposed between the thermal diffuser 110 and the insulating plate 130.

  In the present embodiment, the insulating plate 130 prevents electric leakage to the cooler 140 side, and the metal plate 150 can be used as a power extraction unit for the heating element (semiconductor element) 120.

(Fifth embodiment)
A cooling device 100D of the fifth embodiment is shown in FIG. 5th Embodiment changes the position of the metal plate 150 with respect to the said 4th Embodiment (FIG. 7).

  In the fourth embodiment (FIG. 7), the metal plate 150 is interposed between the thermal diffuser 110 and the insulating plate 130. However, in this embodiment (FIG. 8), the metal plate 150 is a heating element. It is interposed between 120 and the thermal diffuser 110.

  In the present embodiment, since the heating element (semiconductor element) 120 and the metal plate 150 can be brought into direct contact, in the case where the heating element 120 uses a large current, the fourth embodiment (FIG. 7). ), The metal plate 150 can be used as an electric power extraction unit of the heating element 120 so as not to receive the electrical resistance due to the thermal diffusion body 110.

(Sixth embodiment)
FIG. 9 shows a cooling device 100E of the sixth embodiment. 6th Embodiment prescribes | regulates the dimension of the thickness direction of the suitable thermal-diffusion body 110 with respect to the position of the heat generating body 120 in the thermal-diffusion body 110 with respect to the said 3rd Embodiment (FIG. 4).

  In the first thermal diffuser 110A (one of the two laminated bodies) constituting the thermal diffuser 110, the longitudinal direction of the heat conductive plate 111 is the left-right direction in FIG. That is, the high heat conduction direction on the plate surface 110a of the first heat diffusing body 110A is the left-right direction in FIG. 9 in addition to the thickness direction. Further, in the second heat diffusion body 110B (the other laminated body of the two) constituting the heat diffusion body 110, the longitudinal direction of the heat conductive plate 111 is the depth direction in FIG. That is, the high heat conduction direction on the plate surface 110a of the second heat diffusing body 110B is the depth direction in FIG. 9 in addition to the thickness direction. The thickness direction dimension of the first heat diffusion body 110A is t1, and the thickness direction dimension of the second heat diffusion body 110B is t2.

  One heating element 120 is provided on the plate surface 110a of the thermal diffuser 110 (first thermal diffuser 110A). The center position when viewed from above the heating element 120 in FIG. 9 (direction orthogonal to the plate surface 110a) is a. In the plate surface 110a of the first heat diffusion body 110A, the longer one of the distances from the center position a to the end of the first heat diffusion body 110A in the high heat conduction direction (left-right direction) is r1. Further, in the plate surface 110a of the first heat diffuser 110A, in the high heat conduction direction (depth direction) of the second heat diffuser 110B, of the distance from the center position a to the end of the first heat diffuser 110A, The longer one is r2.

In the present embodiment, between the thickness direction dimensions t1 and t2 and the distances r1 and r2,
(Equation 1)
0.5 ≦ (t1 / t2) / (r1 / r2) ≦ 2
The relationship is established.

  In the present embodiment, it can be said that in the first thermal diffusion body 110A, it is preferable that the heat of the heating element 120 be conducted to the distance r1 side as the distance r1 is larger. Similarly, in the second thermal diffusion body 110B, it can be said that it is preferable to conduct the heat of the heating element 120 to the distance r2 side as the distance r2 is larger. And the dimension of the thickness direction of each thermal diffuser 110A, 110B should be thickened or thinned according to the magnitude of the conducted heat. That is, if the distance r1 (r2) is large, the dimension t1 (t2) can be increased. Conversely, if the distance r1 (r2) is small, the dimension t1 (t2) needs to be decreased. Therefore, considering good heat conduction in the thermal diffuser 110, in theory, it is preferable to set (r1 / r2) and (t1 / t2) to the same value, (t1 / t2) / (r1 / That is, r2) = 1 is preferable. Practically, heat conduction in the range of 0.5 to 2.0 can be obtained with respect to the theoretical value 1, thereby obtaining good heat conduction in the heat diffusing body 110. It becomes possible.

  In the present embodiment, the metal plate 150 can be disposed in the same manner as in the fourth embodiment (FIG. 7) or the fifth embodiment (FIG. 8).

(Seventh embodiment)
The cooling device 100F of 7th Embodiment is shown in FIGS. In the seventh embodiment, compared to the first and second embodiments (FIGS. 1 to 3), the thermal diffuser 110 is formed of a plurality of thermal diffusers 110C to 110F, and the thermal diffuser 110 and the insulating plate are further formed. It is assumed that the metal plate 150 described in the fourth embodiment (FIG. 7) is interposed therebetween. Further, one heating element 120 is provided on the plate surface 110a of the thermal diffusion body 110.

  As shown in FIG. 10, the thermal diffuser 110 is formed of four thermal diffusers 110 </ b> C to 110 </ b> F in the present embodiment. Each of the thermal diffusion bodies 110C to 110F is a laminated body in which a plurality of thermally conductive plate materials 111 are laminated, and has a plate shape in which the plate surface 110a extends in a quadrilateral shape. Each thermal diffuser 110C to 110F is spread so that each plate surface 110a is on the same plane, and one corner of each thermal diffuser 110C to 110F is in the same position and adjacent sides are mutually adjacent. It arrange | positions so that it may contact | abut.

  And the circumference | surroundings of the said same position become a form where a part (each corner | angular part) of each thermal-diffusion body 110C-110F is included, and becomes a connection area | region for connecting the heat generating body 120. FIG. The heating element 120 is connected to the connection region, and the heating element 120 is connected to a part (each corner) of each of the thermal diffusion bodies 110C to 110F.

  As shown in FIG. 11 (explained with the thermal diffuser 110C as a representative), the thermal diffusers 110C to 110F are different from the thermal diffuser 110 of the first and second embodiments (FIGS. 1 to 3). The longitudinal direction of the heat conductive plate 111 or the direction of one side 111b is different. Hereinafter, “the longitudinal direction of the heat conductive plate 111 or the direction of one side 111b” is expressed as “the direction of one side 111b of the heat conductive plate 111” according to FIG. 12 described later.

  The direction of one side 111b of the heat conductive plate 111 in each of the heat diffusing bodies 110C to 110F is relative to the four sides L1, L2, L3, and L4 that are the outer peripheral portions of the quadrangular shape in the respective heat diffusing bodies 110C to 110F. It is arranged to be diagonal. More specifically, in this embodiment, the direction of one side 111b of the heat conductive plate 111 is set to an arbitrary point (A) in the connection region to which the heating element 120 is connected, and the respective heat diffusion bodies 110C to 110C. Among the sides L1, L2, L3, and L4 of 110F, the sides included in the outer peripheral portion of the entire thermal diffuser 110 formed by the thermal diffusers 110C to 110F, that is, arbitrary points on the sides L1 and L2 ( It is made parallel to the virtual line connecting B).

  In the present embodiment, an arbitrary point (hereinafter referred to as point A) in the connection region is a position where the corners of each of the thermal diffusion bodies 110C to 110F abut, and any point on the sides L1 and L2 ( Hereinafter, point B) is defined as an intersection (corner) between L1 and L2, and the imaginary line is made equal to one diagonal line extending from point A in each of the thermal diffusion bodies 110C to 110F. Therefore, the direction of the one side 111b of the heat conductive plate 111 in the thermal diffuser 110 is arranged so as to expand outward from the point A (FIG. 10). With the above configuration, among the thermal diffusers 110C to 110F in the thermal diffuser 110, the thermal diffuser 110C and the thermal diffuser 110E that are diagonal to each other are substantially the same, and the thermal diffusion The body 110D and the thermal diffusion body 110F are substantially the same.

  Each said thermal diffusion body 110C-110F can be manufactured as shown in FIG. 12, for example. That is, as described in the second embodiment (FIG. 3), a thermally conductive plate 111 is prepared (FIG. 12A), and a plurality of the thermally conductive plates 111 are laminated in the thickness direction to form a laminate. Form (FIG. 12B), cut along the one side 111b of the heat conductive plate 111 and in the stacking direction to form a primary plate from the stack (FIG. 12C). Furthermore, by cutting off the four corners of the primary plate, a new quadrangular secondary plate inscribed in the primary plate (FIGS. 12 (c) and (d)) Thermal diffusion bodies 110C to 110F in which one side 111b of the heat conducting member 111 is inclined with respect to each side of the secondary plate-like body can be manufactured.

  Alternatively, in the strip-shaped thermally conductive plate material 111, the laminate is sequentially laminated in the plate thickness direction so that the dimension in the longitudinal direction sequentially increases, and further laminated so that the dimension in the longitudinal direction gradually decreases from the middle, and the thermally conductive plate material It is also possible to manufacture the heat diffusing body 110 of this embodiment by making the plate surface 110a formed in the stacking direction by the sides in the longitudinal direction of the 111 into a square shape.

  In the present embodiment, in each of the thermal diffusers 110C to 110F, the direction of the side 111b of the thermally conductive plate 111 is set so as to be parallel to the imaginary line from the point A to the point B. Good thermal conductivity can be imparted in the direction parallel to the imaginary line between points A and B and the thickness direction on 110a. Furthermore, in the thermal diffuser 110 formed by the thermal diffusers 110C to 110F, it is possible to give good thermal conductivity in the direction extending from the point A toward the outer peripheral portion of the thermal diffuser 110 and in the thickness direction. it can.

  Therefore, the heat of the heating element 120 is conducted in the thermal diffusion body 110 so as to spread toward the outer peripheral portion of the thermal diffusion body 110 around the heating element 120 (point A), and in the thickness direction of the thermal diffusion body 110. In addition, since it is possible to conduct well, it is possible to cool the heating element 120 well.

  In the present embodiment, four thermal diffusers 110C to 110F are used in forming the thermal diffuser 110. However, the present invention is not limited to this, and various combinations such as three or more are possible. is there.

  Further, the imaginary line between the points A and B in each of the heat diffusing bodies 110C to 110F is not limited to the diagonal line, and the point A is an arbitrary point in the region for connecting the heating element 120. , B can be set as an arbitrary point on the sides L1 and L2, and can be set as a virtual line connecting the A point and the B point. In short, the direction of the side 111b of the heat conductive plate 111 may be a direction that extends from the connection region of the heating element 120 toward the outer periphery of the heat diffusion body 110.

100A to 100F Cooling device for heating element 110 Thermal diffuser 110A First thermal diffuser 110B Second thermal diffuser 110C to 110F Thermal diffuser 111 Heat transfer plate 112 Inorganic bonding layer (inorganic layer)
120 Heating element 130 Insulating plate 140 Cooler 150 Metal plate

Claims (14)

Thermal diffuser formed as a laminate in which a plurality of strip-like thermally conductive plates (111) having better thermal conductivity in the longitudinal direction and the width direction than in the thickness direction are laminated in the thickness direction Because
In the laminated body, a surface formed in the laminating direction by the side (111a) in the longitudinal direction of the thermally conductive plate material (111) is formed to be a plate surface (110a) extending in a plate shape. ,
A thermal diffusion body characterized in that a direction perpendicular to the plate surface (110a) is a thickness direction. A plurality of the laminates are provided,
The plurality of stacked bodies (110A, 110B) are stacked in the thickness direction and joined by an inorganic layer (112) interposed between the plurality of stacked bodies (110A, 110B),
2. The thermal diffuser according to claim 1, wherein in the adjacent laminates (110 </ b> A and 110 </ b> B), the thermal conductive plate members (111) are arranged so that the lamination directions thereof are different from each other.   The thermal diffuser according to claim 2, wherein an angle formed by the stacking directions of the different thermal conductive plate members (111) is an angle of 85 to 90 degrees.   The inorganic layer (112) is a layer containing at least one of titanium (Ti), nickel (Ni), tin (Sn), lead (Pb), and gold (Au). The thermal diffusion body according to claim 2 or claim 3. A plurality of the laminates are arranged in a direction in which the plate surface (110a) expands, and a part of each plate surface (110a) of the plurality of laminates connects the heating element (120). It is included in the connection area,
In each of the laminates,
The longitudinal direction of the thermally conductive plate (111) of each of the laminates is
An arbitrary point (A) in the connection area;
Out of the outer peripheral portions of each of the stacked bodies, it is parallel to an imaginary line connecting any point (B) on the outer peripheral portion included in the entire outer peripheral portion formed by the plurality of stacked bodies. The thermal diffuser according to claim 1, wherein the thermal diffuser is arranged. The plurality of laminates are composed of four laminates (110C to 110F) in which the plate surface (110a) has a quadrangular shape,
The heat exchange plate according to claim 5, wherein one corner of the quadrilateral shape of each of the stacked bodies (110C to 110F) is included in the connection region.   The thermal diffusion body according to any one of claims 1 to 6, wherein the thermal conductivity in the thickness direction of the laminated body is 600 W / mK or more.   The thermal diffusion body according to any one of claims 1 to 7, wherein the thermal conductive plate (111) is a graphite material or a composite material of graphite and metal. The thermal diffuser (110) according to any one of claims 1 to 8,
A heating element (120) disposed on one of the plate surfaces (110a) of the thermal diffusion body (110);
An insulating plate (130) disposed on the other plate surface (110a) of the thermal diffuser (110);
A cooling device for a heating element, comprising: a cooler (140) disposed on a surface of the insulating plate (130) opposite to the thermal diffusion body (110). The heating element (120) is a semiconductor element (120),
The heating device cooling device according to claim 9, wherein a metal plate (150) is disposed between the heat diffusing body (110) and the insulating plate (130). The heating element (120) is a semiconductor element (120),
The heating element cooling device according to claim 9, wherein a metal plate (150) is disposed between the heating element (120) and the thermal diffusion body (110). The thermal diffuser (110) according to claim 3, wherein the thermal diffuser (110) comprises two of the laminates.
A heating element (120) disposed on one of the plate surfaces (110a) of the thermal diffusion body (110);
An insulating plate (130) disposed on the other plate surface (110a) of the thermal diffuser (110);
A cooler (140) disposed on a surface of the insulating plate (130) opposite to the thermal diffuser (110);
Of the two laminates (110A, 110B) in the thermal diffuser (110), the thickness direction of one laminate (110A) is t1, and the thickness direction of the other laminate (110B) is T2 is the dimension of
In the longitudinal direction of the thermally conductive plate (111) of the one laminate (110A), the distance from the center position of the heating element (120) to the end of the thermal diffuser (110) is r1, the other When the distance from the center position of the heating element (120) to the end of the thermal diffusion body (110) in the longitudinal direction of the heat conductive plate (111) of the laminate (110B) is r2,
Between the dimensions t1, t2 and the distances r1, r2,
0.5 ≦ (t1 / t2) / (r1 / r2) ≦ 2
A heating device cooling device characterized in that the relationship is established. By laminating a plurality of plate-like thermally conductive plate materials (111) having good thermal conductivity in the plane direction compared to the plate thickness direction in the plate thickness direction, a laminate is formed,
The laminated body is cut into a plate shape in the laminating direction along one side (111b) of the thermally conductive plate material (111) to form a plate-like body,
In the plate-like body, a surface formed in the laminating direction by one side (111b) of the thermally conductive plate material (111) is a plate surface (110a) extending in a plate shape,
A method of manufacturing a thermal diffusion body, wherein a direction perpendicular to the plate surface (110a) is a thickness direction. By laminating a plurality of plate-like thermally conductive plate materials (111) having good thermal conductivity in the plane direction compared to the plate thickness direction in the plate thickness direction, a laminate is formed,
The laminated body is cut into a plate shape in the laminating direction along one side (111b) of the thermally conductive plate material (111) to form a primary plate-like body,
In the primary plate-like body, the surface formed in the laminating direction by one side (111b) of the thermally conductive plate material (111) is a plate surface (110a) extending in a plate shape,
The direction orthogonal to the plate surface (110a) is the thickness direction,
A quadrangular shape is formed by cutting off the four corners of the primary plate-like body, and the direction of one side (111b) of the thermally conductive plate material (111) is relative to each side of the square shape formed by the cutting-off. Forming a secondary plate that is slanted,
Preparing a plurality of the secondary plate-like bodies,
A plurality of the secondary plate-like bodies are arranged in a direction in which the plate surface (110b) expands, and a part of each of the plate surfaces (110a) is a connection region for connecting the heating element (120). To be included in the
In each of the secondary plates,
The direction of one side (111b) of the thermally conductive plate (111) of each of the secondary plate-like bodies is
An arbitrary point (A) in the connection area;
Of the outer peripheral portions of each of the secondary plate-like bodies, with respect to a virtual line connecting any point (B) on the outer peripheral portion included in the entire outer peripheral portion formed by the plurality of secondary plate-like bodies A method of manufacturing a thermal diffusion body, characterized by being arranged so as to be parallel to each other.

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