JP2010103278A - Heat dissipation member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a heat-generation part or housing from being damaged when receiving disturbances such as shock, in the configuration where a heat dissipation member for dissipating the heat generated in the heat-generation part is firmly fixed to the heat-generation part and to the housing for housing the heat-generation part, respectively. <P>SOLUTION: The heat dissipation member 6 includes: a joining part 6a which is firmly fixed to a heat-generating part 1; an engaging part 6d for contact engaging with a shielding part 4 provided within the housing 3; and a curvature part 6b and a slope 6c for continuously arranging the joining part 6a and the engaging part 6d. Since the contact engagement is carried out between the engaging part 6d and the shielding part 4, the heat from the heat-generating electronic component 1 can be dissipated heat to the shield part 4 while having shock resistance. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat radiating member that cools a heat-generating component that generates heat when electric power is applied.

  As electronic components that generate heat when electric power is applied, for example, semiconductor lasers applied to optical pickups and the like, integrated circuits used in computers, and the like are known. When such heat-generating electronic components generate heat, wavelength fluctuations occur in the semiconductor laser, and problems such as a slow processing speed occur in the integrated circuit. Therefore, various studies have been made on cooling methods for the heat-generating components.

For example, in Patent Document 1, a heat absorbing plate in which an elastic member is laminated on one surface of a metal foil and a metal foil as a good heat conductive material is interposed between the heat generating surface of the heat-generating semiconductor component and the case subjected to the conductive treatment. It has been proposed that the elastic member is contracted and filled. According to this proposal, the metal foil of the endothermic plate that is bent and filled between the semiconductor component and the housing is pressed by the elastic member, so that there is an effect that the cooling path is efficiently formed by contacting the sheet.
JP 2000-022366 A

  However, in the configuration in which the heat absorbing plate is filled between the heat generating component and the housing in a planar shape as in Patent Document 1 or the like, for example, when receiving an impact such as inadvertent contact with a drop or a foreign object, Since the elastic member is close to the reduction limit, it cannot absorb the shock, and when receiving a continuous shock or when the impact force is large, the circuit board on which the heat-generating component is mounted is screwed to the housing. There is a serious problem that weakening of the fastening force and / or cracking of the substrate occurs.

  Further, in recent years, in order to improve the mounting efficiency on the circuit board, mounting called BGA is generally applied. However, when the heating component is mounted on the BGA, the electrical connection between the heating component and the circuit board is damaged. The issue of giving is also assumed.

  In view of the above-described conventional problems, an object of the present invention is to provide a heat dissipating member that has high heat dissipating efficiency and can suppress damage to a mounting pair on which a heat generating component such as a circuit board is mounted.

  The heat dissipating member of the present invention that solves the above problem is a heat dissipating member that includes a heat dissipating path that dissipates heat generated in the heat generating part to the cooling part, and the heat dissipating path is a joint part fixed to the heat generating part, An engaging portion that abuts and engages with the cooling portion, and a deforming portion that connects the joining portion and the engaging portion and applies a biasing force that abuts and engages the engaging portion with the cooling portion. And a connecting portion.

  The heat dissipating member of the present invention has the above-described configuration, so that the heat dissipation part has a high heat dissipation efficiency to the cooling part by fixing the joint part to the heat generating part, and the heat generating part receives a sudden vibration due to an impact or the like from the outside. Even so, since the vibration can be weakened by the engaging portion, it is possible to realize a heat radiation member having high heat radiation efficiency and high impact resistance.

  Hereinafter, regarding the best embodiment of the heat radiating member of the present invention, a heat generating electronic component mounted on a circuit board as an example of a heat generating part, a heat generating electronic component and a circuit board as an example of a cooling part that dissipates heat generated in the heat generating part. The shield part provided in the housing to be accommodated will be described as an example with reference to the drawings. Moreover, the same code | symbol is provided to the structure which is common in drawing to refer.

  FIG. 1 is a cross-sectional view of a main part of an embodiment of a heat dissipation member of the present invention. 1 is a heat generating electronic component such as an integrated circuit, 2 is a circuit board on which the heat generating electronic component 1 is mounted, and 3 is a circuit board 2 built in. Reference numeral 4 denotes a shield part in which the inner surface of the case 3 is conductively processed, 5 denotes a support member that supports the circuit board 2 with a locking means such as screwing to the case 3, and 6 denotes a heat dissipation member. The heat dissipating member 6 generates heat at a well-known fixing portion (not shown in the figure) such as a heat conductive grease, a conductive adhesive containing a conductive material, a double-sided backing tape, a non-solvent adhesive, and in some cases a metal such as solder. The joint 6a fixed to the electronic component 1, the bent portion 6b for bending the heat radiating member 6 from the side of the heat generating electronic component 1 toward the back surface of the circuit board 2 on which the heat generating electronic component 1 is mounted, and the bent portion 6b and the housing 3 It is the example comprised by the inclination part 6c which connects the engaging part 6d contact | abutted and engaged with the shield part 4 with which it is equipped. That is, in the present embodiment, the deformed portion corresponds to the bent portion 6b, and the joint portion corresponds to the bent portion 6b and the inclined portion 6c.

  Next, a heat conduction path from the heat generating electronic component 1 to the shield part 4 in the present embodiment will be described. When electric power is supplied from the power supply (not shown) from the circuit board 2 to the heat generating electronic component 1, the heat generating electronic component 1 performs a predetermined operation such as calculation in the case of an integrated circuit and laser emission in the case of a semiconductor laser. Heat is generated during operation. The heat generated in the heat generating electronic component 1 is cooled by flowing to the shield part 4 serving as a cooling part via the fixing part, the joining part 6a, the bent part 6b, the inclined part 6c, and the engaging part 6d. As described above, since the heat generating electronic component 1 and the joint portion 6 a are fixedly joined on the surface, the generated heat always flows through the heat radiating member 6. In other words, since only the heat capacity of the heat dissipating member 6 is cooled, at least the joining portion 6a of the heat dissipating member 6 is the heat generating surface of the heat generating electronic component 1 (that is, the surface of the heat generating electronic component 1 fixed by the fixing portion). A sheet shape having the above area is preferable.

  The heat flowing from the heat generating electronic component 1 to the joint portion 6a is transmitted to the shield portion 4 by the engaging portion 6d through the bent portion 6b and the inclined portion 6c. The shield part 4 has a function of suppressing leakage of electromagnetic waves radiated from various electronic components mounted on the circuit board 2 to the outside by performing a conductive process on the housing 3 on the circuit board 2 side. Although it is the original role, as is well known, since the electrically conductive substance has high thermal conductivity, the heat generated by the heat generating electronic component 1 can be cooled by being transmitted to the shield part 4 via the heat radiating member 6. it can.

  Next, a case where an external impact is applied to the heat dissipation member 6 of the present embodiment will be described. The impact force is transmitted from the housing 3 to the circuit board 2 through the support member 5. The transmitted vibration force is converted into vibration in the circuit board 2. This vibration includes a longitudinal vibration mode that vibrates in the vertical direction in the vertical direction of the drawing in the figure indicated by Z, and a plane vibration mode that vibrates in a plane direction orthogonal to the Z direction (shown only in the horizontal direction as X in the drawing). There is. The impact received instantaneously is applied randomly in these directions. As a result, when the circuit board 2 receives the shock, the vibration is not limited to the vertical and horizontal vibrations, but is twisted in the surface direction of the circuit board 2. It becomes a vibration to apply. On the other hand, for example, in the case of a portable device, momentary impact and continuous vibration are applied in the process of storing and carrying in a bag or the like. Under such circumstances, in the configuration of the heat dissipating member filled in a substantially fixed state between the heating element and the casing as in Patent Document 1, vibration is actually transmitted directly to the heating element through the casing. In addition, the electrical connection between the heating element and the circuit board and the support such as a screw between the circuit board and the housing are damaged. On the other hand, in the heat radiating member 6 of the present embodiment, the heat generating electronic component 1 and the joint portion 6a are fixed, but the shield portion 4 and the engaging portion 6d are configured to be in contact with each other. The impact applied to the housing 3 from the electromagnetic wave is propagated to the heat generating electronic component 1 through the support member 5 and the circuit board 2, but can be absorbed by the sliding of the engaging portion 6d and the shield portion 4, All the problems caused by the heat radiating member 6 can be solved.

  The action that can solve this problem will be described in detail. In a normal state in which the electronic device incorporating the heat generating electronic component 1 is not subjected to vibration caused by an impact or the like, the engaging portion 6d is only in contact with the shield portion 4 and is stationary in position. . When the impact received by the electronic device is transmitted from the housing 3, the heat generating electronic component 1 vibrates as described above. When this vibration is in the longitudinal vibration mode in the Z direction and the heat generating electronic component 1 is in a direction away from the housing 3, the locking portion 6 d is on the shield portion 4 due to bending stress due to the bending portion 6 b of the heat radiating member 6. When the heat-generating electronic component 1 is in the direction close to the housing 3, the locking portion 6 d moves over the shield portion 4 to further bend the bending portion 6 b of the heat dissipation member 6. Slide in the A direction. Further, when the vibration is in the plane direction vibration mode in the X direction, when moving in the left direction of the page, that is, in the direction of arrow A, the locking portion 6d slides in the direction of arrow A while being in contact with the shield portion 4, Conversely, when moving in the right direction of the page, that is, in the direction of arrow B, the locking portion 6 d slides in the direction of arrow B while being in contact with the shield portion 4. Further, as described above, when the vibration in the longitudinal direction and the vibration in the plane direction are combined and the vibration of twisting the surface of the circuit board 2 is generated, the locking portion 6d and the shield portion 4 basically have the longitudinal vibration. Although tracking is performed according to the mode and the surface vibration mode, it is assumed that the contact relationship between the locking portion 6d and the shield portion 4 is momentarily lost. Even in such a case, since the heat generated in the heat generating electronic component 1 is transmitted to the heat radiating member 6, the instantaneous contact relationship is not affected at all, and the heat radiating member 6 is further affected. 1 can be maintained in contact with the shield part 4 by making the surface shape spread in the depth direction of FIG. 1, so that the lock part 6d and the shield part 4 substantially contact each other. A relationship can be maintained. In addition, the contact relationship between the locking portion 6d and the shield portion 4 is disengaged because the electrical connection between the heat generating electronic component 1 and the circuit board 2 and / or the support member 5 is applied when an impact is applied. In other words, the influence of the heat radiating member 6 on the support relationship such as screwing for supporting the circuit board 2 and the housing 3 can be suppressed.

  Further, the bent portion 6b has a function of imparting bending resilience (spring property) to the heat radiating member 6 and a function of increasing the heat capacity of the heat radiating member 6 itself by lengthening the heat radiating path of the heat radiating member 6. However, the longer the bent portion 6b, the more the heat radiation effect can be improved.

  In addition, although the bending part 6b in this embodiment was made into the curved shape which has a curvature, in order to bend the heat radiating member 6 in the state over the circuit board 2 like this embodiment, it is generally more advantageous to bend. For this reason, any configuration that can maintain a spring property can be applied even to a configuration that includes a bent portion or a superimposed portion as will be described later.

  As described above, in the present embodiment, the joining portion 6 a fixed to the heat generating electronic component 1 mounted on the circuit board 2 and the engaging portion that comes into contact with the shield portion 4 included in the housing 3 that supports the circuit board 2. 6d is connected to the bent portion 6b so that the heat transfer rate to the shield portion 4 can be kept high regardless of the mode of vibration, and the heat generated in the heat generating electronic component 1 can be maintained. Since the engaging portion 6d that dissipates heat to the shield portion 4 is in contact with the shield portion 4, mechanical damage to the heat-generating electronic component 1, the circuit board 2, and / or the support member 5 due to vibration caused by impact There is an effect that can be suppressed.

  In addition, even when the heat generating electronic component 1 is mounted on the circuit board 2 by BGA with the above configuration, vibration due to impact is not applied to the heat generating electronic component 1, thereby suppressing the main cause of mounting failure. You can also

  In addition, as a material of the heat radiating member that can be applied to the present embodiment and other embodiments described below, there is a particular limitation as long as it is a heat conductive material having flexibility with a restoring force against bending deformation. Rather than malleable metal foils such as aluminum and copper, flexible conductive materials such as carbon materials such as graphite, and other flexible materials such as polyester films, polyamide films or polyimide films Examples thereof include a composite material carried by an isoflexible polymer film and subjected to a conductive treatment such as aluminum.

  In addition, although the heat radiating member 6 of the above-mentioned embodiment demonstrated the structure which thermally radiates to the housing | casing 3 with which the circuit board 2 was supported, it is not limited to this structure, It is a structure of embodiment shown in FIG. May be. In the figure, a circuit board 2 on which a heat generating electronic component 1 is mounted is supported on a housing 3 by a support member 5 by a locking means such as screwing, and is attached to an upper housing 8 that is a housing facing the housing 3. The upper shield part 9 is provided, and the heat generated by the heat generating electronic component 1 is radiated to the upper shield part 9 by the heat radiating member 7. The heat radiating member 7 in the present embodiment includes a joining portion 7a fixed to the heat generating electronic component 1 with a fixing portion (not shown), a bending portion 7b for bending the heat radiating member 7 from the joining portion 7a toward the upper shield portion 9, and a bending portion. In this example, the inclined portion 7c is connected to the engaging portion 7d that contacts the upper shield portion 9b. In other words, in the present embodiment, the deformed portion corresponds to the bent portion 7b, and the connecting portion corresponds to the bent portion 7b and the inclined portion 7c.

  Although the heat radiating member 7 of this embodiment is the structure folded via the bending part 7b between the junction part 7a and the inclination part 7c, generally when the planar heat radiating member 7 is folded by the bending part 7b, it is. Although it does not have sufficient bending resilience (spring property), it can be provided with spring properties by, for example, forming the joint portion 7a and the inclined portion 7c in a bent state.

  In addition, when subjected to vibration caused by an impact or the like, the operations of the joint portion 7a, the bent portion 7b, and the engaging portion 7d of the heat dissipation member 7 in the present embodiment are basically the joint portions 6a of the heat dissipation member 6. Although it is the same as the bending part 6b and the engaging part 6d, the relationship between the engaging part 6d and the shield part 4 which abuts and engages with the shield part 4 provided in the housing 3, and the upper shield part provided in the upper housing 8 The relationship between the engaging portion 7d that abuts and engages 9 and the upper shield portion 9 is different in the following points.

  In other words, since the circuit board 2 is fixed to the housing 3 via the support member 5, it is structurally rigid and relatively resistant to static pressure, but the upper housing 8 is generally shown in FIG. Thus, there are many configurations that are mainly locked to the housing 3 around (not shown in the figure), and therefore often deform when subjected to static pressure. Similarly, for example, when a compressive force is applied from the lateral direction of the paper, it is easily deformed. Thus, in the heat radiating member 7 that radiates heat to the upper shield part 9 in this embodiment, the effect of the engaging part 7d that abuts and engages with the upper shield part 9 that abuts and engages more than the heat radiating member 6 in the previous embodiment. Is expensive. That is, when a force F is applied from the upper surface of the upper housing 8 and the upper housing 8 is deformed in the direction of the housing 3, the engaging portion 7 d slides on the upper shield portion 9 in the arrow A direction and bends. By narrowing the bending angle of the portion 7b in the α direction, it is possible to follow the partial deformation of the upper housing 8. When the application of the force F is released, the bending angle is restored to the original angle by the restoring force of the bent portion 7b, and at the same time, the engaging portion 7d slides on the upper shield portion 9 in the direction of the arrow B and returns to the original angle. Return to the state.

  Thus, according to the structure of the heat radiating member 7 of this embodiment, it can have tolerance also to the vibration resulting from dynamic pressures, such as an impact, similarly to previous embodiment, and also to static pressure. There is also an effect of having resistance against deformation caused by it.

  In the present embodiment, the configuration including the bent portion 7b in which the joint portion 7a and the inclined portion 7c are bent has been described. However, there is a margin in the gap between the heat generating electronic component 1 and the upper housing 8, or the bent portion 7b. If the heat generating electronic component 1 and / or the circuit board 2 have a spatial margin in the direction including the bent portion 6b in the previous embodiment, there is no problem.

  In the above-described embodiment, cooling is performed by releasing heat to the shield portion arranged only on one side. For example, when the heat generation amount of the heat generating electronic component 1 is large and / or vibration due to impact or the like is generated. An example of a countermeasure in the case where the electronic component 1 receives intensely will be described with reference to FIG. The figure shows a heat radiating member 10 in which the structure of the heat radiating member 6 and the structure of the heat radiating member 7 are combined, and a joined portion 10a, a joined portion 10a, and an upper shield portion 9 fixed to the heat generating electronic component 1 by a fixed portion (not shown). From the first inclined portion 10c that connects the first engaging portion 10d that abuts with the second inclined portion 10c, the second inclined portion 10e that extends from the joint portion 10a via the bent portion 10b, and the second inclined portion. A second engaging portion 10f that extends and contacts and engages the shield portion 4 is provided.

  The configuration of the shield part 4 and the second engagement part 10f and the configuration of the upper shield part 9 and the first engagement part 10d in the present embodiment are the same as those of the above-described embodiments, respectively. The same applies to the effects and effects based on the configuration. However, the heat radiating member 10 in the present embodiment includes a first engagement portion 10d that abuts and engages with the upper shield portion 9, and a second engagement portion 10f that abuts and engages with the shield portion 4. Therefore, no matter how the dynamic vibration and / or static pressure is applied to the heat generating electronic component 1, either the first engaging portion 10d or the second engaging portion 10f must be in contact. Therefore, the effect that the heat generation of the heat generating electronic component 1 can be reliably cooled can be achieved. Further, in the heat radiating member 10, the spring property between the joint 10a and the first joint 10d is carried by a bent portion that branches from the bent portion 10b toward the first inclined portion 10c, and the joint 10a and the second joint 10a. In addition to the configuration in which the resilience for bending of the bent portion 10b is responsible for the spring property between the engaging portion 10f, the first engaging portion 10d is in contact with the upper shield portion 9, and the second engaging portion 10f is shielded. Since there is also a spring property due to the contact force with respect to the portion 4, the overall spring property can be made larger than any of the previous embodiments, and the heat dissipation effect can be enhanced. Combined with these, even when the degree of dynamic vibration or static pressure is large or when the heat generation amount of the heat generating electronic component 1 is large, reliable and rapid cooling can be realized.

  In addition, the structure demonstrated in previous embodiment may be sufficient as the structure of the bending part of the junction part 10a and the 1st inclination part 10c, or the bending part 10b.

  The heat radiating members 6, 7, and 10 in any of the embodiments described above basically heat between the heat transfer path between the heat generating electronic component 1 and the shield portion 4 and the upper shield portion 9 such as the heat generating electronic component 1. Although it is a structure provided only with a transmission path | route, the structure which further improved heat isolation by increasing the heat capacity of heat radiating member itself is demonstrated with reference to FIG. The configuration of the heat radiating member 11 in FIG. 4 is basically the same as that of the heat radiating member 7, but the joint portion 7a and the inclined portion 7c of the heat radiating member 7 are bent at the bent portion 7b. It is the structure which improved the thermal capacity of the heat radiating member by providing the superimposition part 11b which extends and bends from each of the junction part 11a and the inclination part 11c.

  The heat radiating member 11 of the present embodiment has the same resistance to impact and static pressure as the heat radiating member 7 described above. However, by providing the overlapping portion 11b in the heat dissipation path of the heat generated in the heat generating electronic component 1, the heat capacity of the heat dissipation member 11 can be increased only by the overlapping portion 11b. For example, the performance of the heat generating electronic component 1 is set low. Thus, when the performance is rapidly increased from a state where the heat generation amount is lowered and the heat generation amount is instantaneously improved, the superimposing unit 11b functions as a buffer for temporarily storing heat, the housing 3, and the upper housing 8 In addition, at least a part of the protruding portion of the overlapping portion 11b shown in FIG. 5 in the perspective view in which the upper shield portion 9 is omitted is formed with another heat radiation path, for example, in a configuration in which it abuts and engages with a side housing (not shown). It is possible to improve the heat dissipation efficiency. Note that the overlapping distance L of the overlapping portion 11b can be appropriately set according to dimensions such as the size of the gap.

  In addition, the overlapping part 11b in this embodiment applies the material similar to the adhering part which adhere | attaches the junction part 11a and the heat-emitting electronic component 1 to the opposing side of the junction part 11a and the inclination part 11c, and join part 11a. In addition, surface heat transfer between the inclined portion 11c and the inclined portion 11c can be achieved, and the heat conduction efficiency to the inclined portion 11c can be improved, and the spring property to the engaging portion 11d can be improved as compared with the bending by the bent portion 7b. There is also an effect.

  Moreover, although the heat radiating member 11 of this embodiment demonstrated the structure which thermally radiates only to the upper side shield part 9, even if it is the structure radiated | emitted to the shield part 4 of FIG. 1, for example, it can apply without any problem. In the case of this configuration, it is only necessary to make a minor change simply by providing an overlapping portion on a part of the curved shape in the bent portion 6d of FIG.

  In the present embodiment, as described above, the configuration is such that only the upper shield portion 9 dissipates heat. However, as described above, for example, when the heat generation electronic component 1 generates a large amount of heat and / or vibrations due to impact or the like generate heat generation electrons. For example, when the component 1 is violently received, the invention can be applied to a configuration in which heat is radiated to both the shield part 4 and the upper shield part 9. An example thereof will be described with reference to FIG. The figure is a perspective view showing only the heat generating electronic component 1, the circuit board 2 and the heat radiating member 12, omitting the casing 3, the shield part 4, the upper casing 8 and the upper shield part 9 for easy visual recognition. The joining part 12a of the heat radiating member 12 is fixed to the heat generating electronic component 1 by a fixing part as in the above-described embodiment. The heat generated in the heat-generating electronic component 1 is radiated from the first engaging portion 12d to the upper shield portion via the first inclined portion 12c, and the second inclined portion 12 configured to straddle the circuit board 2 with the bent portion 12b. Heat is radiated from the second engagement portion 12f to the shield portion via electrons.

  In addition, as shown in the figure, the 1st inclination part 12c and the junction part 12a in the heat radiating member 12 are another members, and are being fixed by the fixing | fixed part with which the superimposition part 12g is equipped. As a material applied to the fixing portion, a material for fixing the joining portion 12a and the heat generating electronic component 1 can be used, and heat flowing in the joining portion 12a in the area of the overlapping portion 12g is applied to the first engaging portion 12d. introduce. By using the first inclined portion 12c and the second inclined portion 12e as separate members, it is easy to control the spring property generated by the bending at the overlapping portion 12g, and the first shield portion 12c can be controlled with respect to the upper shield portion. The abutting engagement force of the engaging portion 12d can be surely achieved.

  In the above-described embodiment, the electronic component mounted on the circuit board as the heat generating part has been described as an example. However, as a specific example of the electronic component, a semiconductor applied to an integrated circuit, an optical pickup, or the like that performs operations such as a computer. Laser light source, LED light source applied to the backlight of display panels such as liquid crystal panels that display images with shutter function, plasma light emitting part of plasma display, and other heat generating parts in a wide range of fields such as thermal fixing parts of copiers, etc. Can be applied.

  In the above-described embodiment, the case where the shield portion is applied as the heat radiating member has been described.For example, when the heat generation amount of the heat generating component is large, the heat capacity of the heat radiating member is increased. It can also be changed as appropriate.

  Since the heat radiating member of the present invention has resistance against disturbance and high heat transfer coefficient, it can be applied to a wide range of product fields from portable devices to large stationary devices.

Sectional drawing which shows the principal part which shows the structure of one Embodiment in the thermal radiation member of this invention. Sectional drawing which shows the principal part which shows the structure of other embodiment in the thermal radiation member of this invention. Sectional drawing which shows the principal part which shows the structure of another embodiment in the heat radiating member of this invention. Sectional drawing which shows the principal part which shows the structure of further another embodiment in the thermal radiation member of this invention. Main part perspective view showing the configuration of the same embodiment The principal part perspective view which shows the structure of another embodiment in the thermal radiation member of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat generating electronic component 2 Circuit board 3 Housing | casing 4 Shield part 5 Support member 6 Heat radiation member 6a Joint part 6b Bending part 6c Inclination part 6d Engagement part

Claims (2)

A heat dissipating member having a heat dissipating path for dissipating heat generated in the heat generating part to the cooling part,
The heat dissipation path is
A joint fixed to the heat generating part;
An engaging portion that abuts and engages the cooling portion;
A heat radiating member provided with a joint part which has a deformation part which connects the joint part and the engagement part, and gives energizing force which the engagement part contacts and engages with the cooling part. The heat generating portion includes a first surface of the heat generating portion that fixes the joint portion, and a second surface disposed to face the first surface,
A first cooling portion disposed at a first predetermined distance from the first surface via the joint, and a second predetermined distance from the second surface. The heat radiating member according to claim 1, further comprising a second cooling unit.