JPH05218245A - Semiconductor device and heat sink therefor - Google Patents

Abstract

PURPOSE:To enable a semiconductor device to exert a more excellent heat radiating effect as compared with the conventional semiconductor device while the semiconductor device maintains a simple structure and excellent manufacturability. CONSTITUTION:A plurality of protruding sections 20 which are extended outward from a pillar post 12 side so that the sections 20 can be protruded on one surface and recessed on the other surface against a plurality of thin plate fins 14 fixed to the post 12, is integrally provided in a heat sink 10 in such a state that the sections 20 are roughly arranged in the radial direction and passages 22 which pass through both surfaces of the plate fins 14 are formed by opening both sides of the sections 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a heat sink for a semiconductor device, and more particularly to an improved semiconductor device and a heat sink for a semiconductor device that can exhibit an excellent heat dissipation effect.

[0002]

2. Description of the Related Art Generally, in a semiconductor component that generates a large amount of heat, such as an IC such as an LSI or a thyristor such as an SCR that constitutes an electric circuit in various electronic devices, a heat sink is used to prevent the heat from increasing. It is configured as a semiconductor device integrally provided with such a heat sink. That is, in such a semiconductor device, a plurality of thin plate-shaped plate fins extending in the direction perpendicular to the axis are attached to a heat sink that is externally inserted and fixed at predetermined intervals in the axial direction with respect to a columnar post. In contrast, the structure is such that a semiconductor component, which is an object to be cooled, is attached to one end side of the post in the axial direction, and the heat of the semiconductor component transmitted through the post is transferred between the plate fins in the plate fin portion. It is designed to dissipate heat to the circulating cooling air.

By the way, in such a semiconductor device, various improvements have been conventionally made to the heat sink in order to improve the heat radiation effect. For example, Japanese Utility Model Laid-Open No. 59-9549. For each plate fin, by providing a plurality of protrusions protruding on the surface,
There has been proposed a structure in which a turbulent flow is generated in the cooling air flowing between the plate fins.

However, in the heat sink having such a structure, although the cooling efficiency can be improved to some extent by the turbulent flow of the cooling air between the plate fins, the plate of the boundary film which hinders the heat radiation is provided. It was difficult to prevent the formation on the fin surface, and it was still difficult to obtain a satisfactory heat dissipation effect.Because the plurality of protrusions are arranged in one direction, the ventilation direction of the cooling air is However, there is an inherent problem that the ventilation resistance is increased with respect to ventilation from different directions and the number of protrusions is limited.

In Japanese Utility Model Laid-Open No. 62-182600, ventilation holes penetrating both sides of the plate fin are formed at corresponding positions of the plate fins, and cooling is performed in the axial direction of the post through the ventilation holes. A structure that allows air to flow has been proposed. In such a structure, although the flowability of cooling air between the plate fins can be improved, the formation of ventilation holes allows the plate fins to be formed. Since the heat transfer path from the post side to the outside in the above is blocked and the heat flow on the plate fins is blocked, the improvement of the heat radiation effect as a whole was hardly expected.

In short, the conventional semiconductor device provided with such a heat sink has not yet been able to obtain a sufficient heat dissipation effect. Therefore, it has been earnestly desired to realize a semiconductor device having a better heat dissipation effect, and particularly in recent years. The demand is increasing with the miniaturization of electronic devices in.

[0007]

The present invention has been made in view of the circumstances as described above, and the problem to be solved by the present invention is, as compared with the conventional semiconductor device as described above,
An object of the present invention is to provide an improved semiconductor device and a heat sink for a semiconductor device, which can exhibit a better heat dissipation effect while ensuring a simple structure and excellent manufacturability.

[0008]

In order to solve such a problem, according to the present invention, a plurality of thin plate-shaped plate fins extending in a direction perpendicular to an axis are spaced apart from each other by a predetermined distance in the axial direction with respect to a columnar post. In the semiconductor device in which a heat sink that has been externally inserted and fixed is used, and a semiconductor component that is an object to be cooled is attached to one end side of the heat sink in the axial direction of the post, A plurality of protrusions that extend outward from the post side and that are convex on the other side and concave on the other surface are integrally provided so as to be substantially radial as a whole, and both side portions of the protrusions are opened. At the very least, the feature is that passages are formed through both sides of the plate fin.

According to the present invention, in the semiconductor device as described above, each of the plurality of projecting portions of each plate fin of the heat sink constituting the semiconductor device is convex on the surface of the object to be cooled attached to the post. What is formed so that is also the feature.

Further, in the present invention, in the semiconductor device as described above, protective plates having higher rigidity than the plate fins are provided at both ends in the axial direction of the post in the heat sink constituting the semiconductor device. In one of the plates, such a post is attached to the semiconductor component, or a protection plate having a rigidity higher than that of the plate fin is integrally formed on one end side in the axial direction of the post. The feature is that the post is attached to the object to be cooled via a protective plate.

Furthermore, the present invention also provides a semiconductor device in which a hollow hole extending in the axial direction is provided inside the post,
That is the feature.

Further, according to the present invention, a plurality of plate fins which are externally inserted and fixed to the columnar post at predetermined intervals in the axial direction so as to spread in the direction perpendicular to the axis. , A plurality of projecting portions extending outward from the post side, which are convex on one surface and concave on the other surface, are integrally provided so as to be substantially radial as a whole, and The heat sink for a semiconductor device, which constitutes the semiconductor device as described above, is also characterized in that both sides of the plate fin are opened to form passages penetrating both sides of the plate fin.

[0013]

In other words, in the semiconductor device constructed according to the present invention as described above, the projections of the plate fins forming the heat sink are formed in a substantially radial array form as a whole, and Since both sides of the projecting portion are opened to form a passage from one surface side of the plate fins to the other surface side, the cooling air flowing between the plate fins is It can also be smoothly flowed through, and when passing through the protrusion, it is divided into its convex side and concave side by the opening of the protrusion, and the plate fins of the plate fin pass through the passages that open on both sides of the protrusion. By causing the flow to be divided into both sides, the boundary layer having the fluid velocity distribution and the temperature distribution in the cooling fluid is divided, and the boundary layer Raw or growth can be advantageously suppressed or prevented, and furthermore, the passages provided in the projections of such plate fins are provided on both sides of the projections extending substantially radially outward from the post side. Since it is opened in the portion and is formed substantially parallel to the heat transfer direction, it does not interrupt the heat transfer path.

Further, in such a semiconductor device, the projecting portions of the plate fins constituting the heat sink are formed as a whole in a substantially radial shape extending outward from the center, and these projecting portions are used. Since the direction in which the cooling fluid should flow is not limited, it also has a manufacturing advantage that the plate fins can be assembled to the posts without considering the directionality. ing.

Therefore, according to the present invention, it is possible to dramatically improve the cooling efficiency by the fluid that is made to flow between the plate fins without significantly complicating the structure or decreasing the manufacturability. Therefore, a semiconductor device capable of exhibiting an extremely excellent heat dissipation effect can be advantageously realized.

Further, in the semiconductor device according to the present invention, each of the projecting portions of each plate fin is formed so as to be convex on the surface of the semiconductor component side to be mounted on the post. In the plate fin located on the outermost side in the direction, the height of the heat sink and the entire semiconductor device can be reduced by avoiding the protrusion of the protrusion to the outside. It can be realized.

Further, in the semiconductor device according to the present invention, in which protective plates are provided at both ends of the post in the axial direction, the plate fins are protected by the protective plates, and the plate fins are protected from other members. There is an advantage that direct contact can be avoided and the deformation and damage can be effectively prevented.

Furthermore, in a semiconductor device according to the present invention in which such a post is attached to a semiconductor component via a protective plate which is integrally formed on one end side in the axial direction of the post, the assembly (attachment) ) The workability is excellent, the protective plate for protecting the plate fins can be advantageously formed, and the heat transfer between the semiconductor component and the post can be effectively improved.

[0019]

The embodiments of the present invention will now be described in detail with reference to the drawings in order to clarify the present invention more specifically.

First, FIGS. 1 and 2 show a specific example of a heat sink which constitutes a semiconductor device according to the present invention.

Reference numeral 10 denotes a heat sink, which is provided with a post 12 having a solid columnar shape with a circular cross section at its central portion. The post 12 is formed of a material having excellent heat transfer properties and corrosion resistance to the use environment, such as copper or aluminum alloy. Further, as is apparent from FIG. 1, a plurality of (seven in the present embodiment) plate fins 14 are attached to the post 12 in a form in which they are stacked at a predetermined interval.

The plate fins 14 constituting the heat sink 10 have a thin plate-like rectangular flat plate shape,
At the center thereof, a cylindrical mounting portion (collar) 16 protruding at a predetermined height on one surface is provided. Then, in the inner hole 18 of the mounting portion 16, the post 12 is externally inserted and assembled, so that the mounting portions 16 are attached to each other in the axial direction of the post 12 in a state of spreading in the direction perpendicular to the axis of the post 12. The post 12 is fixed to the post 12 by being overlapped with each other with a space corresponding to the protruding height. The plate fins 14 are fixed to the posts 12 by, for example, press-fitting the posts 12 into the mounting parts 16 of the plate fins 14 so that the mounting parts 16 are fitted to the posts 12 or the mounting parts 16 are fixed. This is done by brazing the inner peripheral surface of the inner hole 18 to the outer peripheral surface of the post 12.

Also, these plate fins 14 have
Each of the narrow elongated projecting portions 20 having a convex surface on one side and a concave surface on the other side, respectively, has an arrangement form that is generally radial in a state of extending outward from the mounting portion 16 side, A plurality is formed. Further, in each of these projecting portions 20, through holes (passages) 22, 22 which are opened at both side portions thereof and penetrate through both surfaces of the plate fin 14 are formed.

That is, the protrusions 20 extend in the heat flow direction from the post 12 side to the outside.
It is formed with a narrow and narrow bridge shape, whereby a through hole 22 provided on the side of the protrusion 20 is formed.
Is also formed so as to extend in the heat flow direction. Therefore, even if the through holes 22 are formed, the plate fins 14 are not blocked in the heat flow direction, and the heat transfer from the post 12 side is advantageous over the entire surface of the plate fins 14. It can be done.

By the way, it is desirable that the projecting portion 20 is formed at a height which does not contact the adjacent plate fins 14. In consideration of member strength, economy, and manufacturability, the plate fins 14 are practically used. The plate thickness of 14 is 0.1
The arrangement interval of the plate fins 14, that is, the protruding height of the mounting portion 16 is set to about 1.5 to 3.5 mm, and the height of the protruding portion 20 is set to about 1.0 mm. Will be set to a ratio of about 0.3 to 0.7 times the arrangement interval.

The plate fin 1 having such a structure
In the case of No. 4, similarly to the post 12, it is formed by using a material having excellent heat transferability and corrosion resistance against the use environment and having excellent workability, such as copper or aluminum alloy. Then, as described above, the mounting portion 16
The plate fins 14 having the protrusions 20 are formed by, for example, pressing a rectangular flat plate material, more specifically, forming the mounting portions 16 by burring. The protrusion 20 is formed by the above method, and at the same time when the protrusion 20 is formed, both sides of the protrusion 20 are cut to form the through holes 22, 22, which can be advantageously formed.

Further, a pedestal 24 is fixed to one end in the axial direction of the post 12 to which a large number of plate fins 14 are assembled in this way, while a top plate 26 is fixed to the other end in the axial direction. Has been done. As shown in FIGS. 3 and 4, the pedestal 24 and the top plate 26 are formed to have substantially the same planar shape as the plate fin 14, and are thicker than the plate fin 14. Therefore, it has high rigidity. The pedestal 24 is made thicker than the top plate 26.

Since the plate fins 14 are positioned between the pedestal 24 and the top plate 26, the pedestal 24 and the top plate 26 protect the plate fins 14 and the heat sink. 10
It is possible to prevent the plate fin 14 from being deformed or damaged due to abutting of other members at the time of manufacturing, transporting, or assembling to a device.

The pedestal 24 and the top plate 26 are also formed of, for example, copper or aluminum alloy, similarly to the plate fins 14, and are press-fitted, welded, brazed, etc. to the post 12. Will be fixed by. Further, as is apparent from the above description, in this embodiment, the pedestal 24 and the top plate 26 form a protective plate.

Furthermore, as shown in FIG. 4, a junction 28 having a thin disk shape is fixedly provided on the surface of the pedestal 24 opposite to the post 12. Similar to the plate fin 14, the junction 28 is also made of, for example, copper or aluminum alloy, and is fixed to the outer surface of the pedestal 24 by welding, brazing, or the like.

Further, in the heat sink 10 having such a structure, as shown in FIG. 5, a semiconductor chip such as a Si chip is housed inside the outer surface of the pedestal 24. A semiconductor package (semiconductor component) 32 as an object to be cooled is attached, and thereby a target semiconductor device is obtained. In addition, in FIG.
34 is a lead pin.

By the way, the mounting of the semiconductor package 32 to the pedestal 24 is performed by, for example, bonding using a thermosetting adhesive, soldering, or the like, and under such a mounting state, the junction is formed. A semiconductor chip (not shown) housed in the semiconductor package 32 is attached to the attachment surface 30 (see FIG. 1) 28.

In the semiconductor device having such a structure, the heat generated in the semiconductor package 32 is applied to the heat sink 10 at the junction 28.
The heat is transmitted to the plate fins 14 via the pedestal 24 and the posts 12, and the plate fins 14 radiate heat to the cooling air flowing between the plate fins 14.

Here, in such a heat sink 10, the protrusion 20 provided on the plate fin 14 is provided.
However, since they are arranged in a radial form as a whole, the cooling air that is made to flow between the plate fins 14 can be flowed without having a specific directionality, and
Since the through holes 22 are formed on both sides of each protrusion 20, the flow resistance exerted on the cooling air by the protrusion 20 can be advantageously suppressed, and the cooling air can be smoothly passed. It will be.

When the cooling air flowing between the plate fins 14 passes through the projecting portion 20, the projecting portion 20 and the through hole 22 allow the cooling air to flow.
Is divided into a convex surface side and a concave surface side, and is made to flow to both sides of the plate fin 14 through through holes 22 that open at both sides of the protruding portion 20, whereby the velocity boundary layer and the temperature boundary layer in the cooling air are separated. Can be divided and can be reduced or eliminated very effectively, and the cooling efficiency of the plate fins 14 by the cooling air can be significantly improved.

Further, since the projections 20 are formed in the plate fins 14 in a radial arrangement as a whole, they are positioned at intervals in the cooling fluid flow direction. Therefore, the separation of the boundary layer of the cooling fluid by the protrusions 20 can be more effectively performed, and the growth of the boundary layer can be effectively prevented.

Further, the through holes 22 provided on both sides of the projecting portion 20 of the plate fin 14 are formed in a slit shape extending in the heat transfer direction of the plate fin 14, and the heat transfer of the plate fin 14 is performed. Since the path is not cut off or the path is not significantly reduced, excellent heat conductivity or heat diffusivity in each plate fin 14 can be secured, and the cooling efficiency of the plate fin by the cooling air is improved. Together with this, an extremely excellent heat dissipation effect can be exhibited.

Further, as described above, in the plate fin 14 in which the plurality of protrusions 20 are radially arranged, the protrusions 20 may limit the direction in which the cooling fluid should flow. Since it does not exist, it has an advantage in manufacturing that the plate fin 14 can be assembled to the post 12 without considering the directivity.

Further, in the heat sink 10 which constitutes the semiconductor device in this embodiment, each plate fin 1
4 is formed so as to be convex on the surface of the post 12 on the side where the IC is mounted, and the projection 20 of the plate fin 14 on the outermost side to which the top plate 26 is mounted. Since the protrusion to the outside is avoided, the top plate 26 can be provided closer to the outermost plate fin, and thus further compactification can be achieved.

Furthermore, in the heat sink 10 constituting the semiconductor device according to the present embodiment, the plate fins 14 are protected by the pedestals 24 and the top plate 26 provided at both axial ends of the post 12. Therefore, there is an advantage that damage during transportation or assembly to a device can be effectively prevented, and a desired heat radiation effect can be stably exhibited.

Although one embodiment of the present invention has been described in detail above, this is a literal example and the present invention should not be construed as being limited to such a specific example.

For example, the shape of the protrusions 20 formed on the plate fins 14 does not block or significantly reduce the heat transfer path extending from the post 12 side to the outside.
Post 1 so that through holes (passages) can be formed on both sides.
It may be formed so as to extend outward from the second side, and for example, may be formed in a substantially radial shape as shown in FIG. In addition, in FIG. 6, in order to facilitate the understanding thereof, with respect to members and parts having the same structure as that of the above-mentioned embodiment, respectively,
The same reference numerals as in the above-mentioned embodiment will be given.

Further, the protrusions may be formed in different patterns on each plate fin 14, or a plurality of protrusions protruding on different faces may be formed on one plate fin 14. It can also be formed.

Further, even if each of the plurality of projecting portions of each plate fin 14 is formed to be concave on the surface of the object to be cooled attached to the post, there is no problem in terms of heat dissipation effect. Nor.

Further, the pedestal 24 or the top plate 26 is attached to the post 1
Even if it is formed integrally with the axial end portion of 2, the heat conductivity that can be transmitted between the two members 24, 12 by forming the pedestal 24 integrally with the post 12 does not matter. However, it can be advantageously improved.
However, the protection plates such as the pedestal 24 and the top plate 26 are
In the present invention, it is not essential.

Furthermore, it is possible to provide a hollow hole extending in the axial direction by a predetermined length or penetrating in the axial direction in the post 12, whereby the heat radiation effect can be further improved. Becomes

Although not listed one by one, the present invention is
It can be carried out in a mode in which various changes, modifications, improvements, etc. are added based on the knowledge of those skilled in the art.
It goes without saying that all such embodiments are included in the scope of the present invention without departing from the spirit of the present invention.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a heat sink which constitutes a semiconductor device as an embodiment of the present invention.

2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a top view of FIG.

FIG. 4 is a bottom view of FIG.

5 is a vertical cross-sectional view showing the entire semiconductor device including the heat sink shown in FIG.

FIG. 6 is a cross-sectional view showing another embodiment of a semiconductor device configured according to the present invention.

[Explanation of symbols]

 10: Heat sink 12: Post 14: Plate fin 16: Mounting part 20: Projection part 22: Through hole 24: Pedestal 26: Top plate 32: Semiconductor package

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Kishio Morishige 5-7 Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor Yoshio Sato 5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industry Co., Ltd.

Claims (6)

[Claims] 1. A heat sink in which a plurality of thin plate plate fins extending in a direction perpendicular to an axis are externally inserted and fixed to a columnar post at predetermined intervals in the axial direction. On one end side in the axial direction of the post,
In a semiconductor device to which a semiconductor component, which is an object to be cooled, is attached, a plurality of protrusions extending outward from the post side that are convex on one surface and concave on the other surface with respect to the plate fin. The semiconductor device is characterized in that the parts are integrally provided so as to be substantially radial as a whole, and both sides of the projecting parts are opened to form passages penetrating both surfaces of the plate fin. 2. The semiconductor device according to claim 1, wherein each of the plurality of projecting portions of each plate fin is formed so as to be convex on a surface of a semiconductor component side attached to the post. 3. A protection plate having rigidity higher than that of the plate fins is provided at both ends of the post in the axial direction, and the post is attached to the semiconductor component in one of the protection plates. 3. The semiconductor device according to claim 1 or 2. 4. A protection plate having rigidity higher than that of the plate fins is integrally formed on one end side in the axial direction of the post, and the post is attached to the semiconductor component via the protection plate. Claim 1
4. The semiconductor device according to any one of 3 to 3. 5. The semiconductor device according to claim 1, wherein a hollow hole extending in the axial direction is provided inside the post. 6. A plurality of thin plate plate fins extending in a direction perpendicular to the axis are provided at predetermined intervals in the axial direction with respect to a columnar post to which a semiconductor component, which is an object to be cooled, is attached at one end side in the axial direction. A heat sink for a semiconductor device, which is externally inserted and fixed, wherein a plurality of projecting portions extending outward from the post side are convex on one surface and concave on the other surface with respect to the plate fin. Is integrally provided so as to be substantially radial as a whole, and both sides of the projecting portions are opened to form passages penetrating both sides of the plate fin.