JPH06224326A - Radiator and semiconductor package using this radiator - Google Patents

Abstract

PURPOSE:To make it possible to enhance heat emission properties without damaging the molding performance and further reduction in a thin wall of a package. CONSTITUTION:In a semiconductor package 50 which uses a film carrier 30 resin-sealed with a die, a semiconductor element 1 is loaded on the film carrier 30 which comprises a film base material 3 and a pattern-formed lead 2. The semiconductor element 1 is loaded on a radiation board 6 of a radiator 5 which comprises the radiating board 6 and a plurality of legs 7 and sealed with resin 4 where between a radiating surface 6b of he radiating board 6 and the ends 7a of the legs 7 are exposed the radiating surface of the radiating board 6 and the ends 7a of the legs 7 having a similar height with the semiconductor package from both sides of the semiconductor package 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiator for radiating heat generated by a semiconductor element and a semiconductor package using this radiator.

[0002]

2. Description of the Related Art Conventionally, as a semiconductor package of this type, a semiconductor element 1 bonded to a lead 2 of a film substrate 3 is mounted on a metal plate 60 as shown in FIG. There is a semiconductor package 50 which is sandwiched by a mold (not shown) composed of and is resin-sealed with the resin 4.

Further, as described in Japanese Patent Application Laid-Open No. 2-63143, a heat dissipation cap is formed, and a flange portion of the cap is brought into close contact with a carrier tape to expose the heat dissipation fin portion of the cap from the package. There was something I took.

[0004]

However, when the conventional metal plate 60 as shown in FIG. 9 is used to perform resin sealing, the pressure of the resin 4 causes the resin 4 to wrap around the bottom surface of the package 50 and the metal plate. 60 floats and package 5
It cannot be exposed on the bottom of 0. When the resin 4 wraps around the exposed surface of the metal plate 60 as described above, there is a problem in that the heat radiation performance of the heat generated by the semiconductor element 1 is extremely deteriorated. Moreover, when mounting the package 50 on the substrate,
Since the resin 4 is interposed between the substrate and the metal plate 60, the thermal conductivity and the electrical conductivity to the substrate are deteriorated, and the heat dissipation and the electrical stability are significantly deteriorated. Further, if the resin 4 wraps around the exposed surface of the metal plate 60, the appearance of the package 50 may deteriorate.

By the way, when the package size becomes thin, the fluidity of the resin for resin encapsulation becomes larger as the height of the package becomes thinner, and the resistance of the resin becomes larger in proportion to the thinness of the package. Becomes worse. When the fluidity of the resin deteriorates, it solidifies without filling the resin in the mold,
The resin cannot be sealed. In particular, as in the above-mentioned known example,
In the structure in which the semiconductor element is surrounded by the heat dissipation cap, the heat dissipation cap significantly impedes the flow of the resin. Therefore, there is a problem that the yield is significantly deteriorated due to defective molding of the package and it is extremely difficult to make the package thin.

Therefore, the present invention has been made in order to solve the above-mentioned problems, and it is a radiator that can improve the heat radiation without impairing the moldability and the thinness of the package, and a semiconductor package using this radiator. The purpose is to provide.

[0007]

In order to solve the above problems, the present invention provides a radiator for radiating heat generated by a resin-sealed semiconductor element in a semiconductor package, which has a larger area than the semiconductor element. A heat dissipation plate that covers the back surface of the semiconductor element is provided with a plurality of leg portions that are substantially the same height as the thickness of the semiconductor package and are separated from each other.

Further, according to the present invention, in a radiator for radiating heat generated by a semiconductor element sealed in a semiconductor package with a resin, a radiator plate having an area larger than the semiconductor element and covering a back surface of the semiconductor element is provided. A plurality of leg portions having a height higher than the thickness of the semiconductor package and having elasticity are provided separately from each other.

Further, according to the present invention, in a semiconductor package in which a semiconductor element is mounted on an insulating film substrate having a large number of conductive leads and resin-sealed, a heat dissipation plate having an area larger than that of the semiconductor element, A heat radiator comprising a plurality of legs provided apart from each other is provided on the heat radiation plate, one surface of the heat radiation plate is brought into contact with the back surface of the semiconductor element, and the other surface is provided on one side of the semiconductor package. In addition to being exposed to the outer surface, the end portions of the plurality of legs are exposed to the other outer surface of the semiconductor package.

In each of the above constructions, the leg portion may be provided with a cutout portion, and further, the leg portion may be provided with an end portion having a supporting surface parallel to the heat dissipation plate.

[0011]

According to the present invention having the above-described structure, one of the molds presses a plurality of legs in the upper and lower molds used for resin sealing, so that the heat dissipation of the heat dissipation plate is prevented. Since the side surface is pressed against the other die, the heat radiating surface of the heat radiating plate is in close contact with the die, is not affected by the pressure of the resin, and can prevent the resin from wrapping around the exposed surface of the heat radiating plate. For this reason,
The heat dissipation of the heat generated by the semiconductor element is improved.

Further, when the plurality of legs are made to exhibit elasticity,
The adhesion of the heat sink to the mold is further improved. further,
If a supporting surface parallel to the heat dissipation plate is provided at the end of the leg, the pressing by the mold becomes more reliable and heat can be dissipated from the supporting surface at the end.

Moreover, since the plurality of leg portions are provided separately from each other, the space between the leg portions is opened, and the leg portions are provided with the cutout portions. The semiconductor package can be reliably molded without disturbing the flow of the semiconductor package.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. 1 is a sectional view of the semiconductor package, FIG. 2 is a sectional view of the semiconductor package taken along the line AA of FIG. 1, and FIG.
[Fig. 4] is a perspective view of a radiator with a semiconductor element mounted thereon, and Fig. 4 is an enlarged perspective view of legs of the radiator.

As shown in FIG. 1, this semiconductor package 50 uses a film carrier 30 composed of an insulating film base material 3 and a large number of conductive leads 2 patterned on the insulating film base material 3. The semiconductor element 1 is connected to the inner lead 2 ′ protruding inside the device hole 10 in the film carrier 30 via the bump 20 by an inner lead bonding process.

The semiconductor element 1 mounted on the film carrier 30 is mounted on the heat absorption surface 6a of the heat dissipation plate 6 of the radiator 5.

Here, as shown in FIG. 3, the radiator 5 is
It is integrally formed of a metal material having good thermal conductivity such as aluminum or copper, and is composed of a flat heat dissipation plate 6 and a plurality of legs 7.

The heat dissipation plate 6 has a larger area than the bottom surface of the semiconductor element 1, and the semiconductor element 1 and the heat dissipation plate 6 are shown in FIG.
The relationship is as shown in.

As shown in FIG. 3, the leg portion 7 is provided with a heat radiating plate 6.
Are provided so as to support each of the legs 7 and each leg 7 is open. In this embodiment, the leg portions 7 are provided at each corner of the heat dissipation plate 6. Then, the leg portion 7 is slightly inclined with respect to the vertical direction with respect to the radiator plate 6 (∠θ in FIG. 1).
<90 °), and is configured to have elasticity.
Further, as shown in FIG. 4, the leg portion 7 has a bent end portion 7 a, and the end portion 7 a is parallel to the heat dissipation plate 6 and the supporting surface 7 is provided.
b. Further, the leg portion 7 is provided with a cutout portion 7c.

As shown in FIG. 1, the semiconductor element 1 placed on the heat dissipation plate 6 is adhered by an adhesive 8 having electrical conductivity and heat dissipation. A silver paste or the like is used as the adhesive 8.

The film carrier 30 having the semiconductor element 1 mounted thereon and the radiator 5 are sandwiched by a mold (not shown) consisting of an upper mold and a lower mold, and sealed with a resin 4.

Here, at the time of sealing with the resin 4, the end portion 7a of the leg portion 7 is pressed by the upper die, so that the heat radiating surface 6b which is the bottom surface of the heat radiating plate 6 is brought into close contact with the lower die. Since the leg portion 7 is slightly tilted with respect to the heat radiating plate 6 from the vertical, the leg portion 7 exerts elasticity and the heat radiating surface 6b of the heat radiating plate 6 can be pressed against the lower mold, so that it is more closely attached to the mold. Will increase
The heat radiation surface 6b of the heat radiation plate 6 and the support surface 7b of the end portion 7a of the leg portion 7
And are exposed from both sides of the semiconductor package 50. Further, the radiator 5 has a height h substantially the same as that of the semiconductor package 50.
Will have.

According to the present embodiment configured as described above, the radiator plate 6 and the end portions 7a of the leg portions 7 are in close contact with the mold used for resin sealing, so that the radiator 5 is the semiconductor package 50. And the heat sink 6 does not float, and the heat sink 6
It is possible to prevent the resin 4 from wrapping around the heat radiation surface 6b. Since the heat dissipation surface 6b of the heat dissipation plate 6 and the ends 7a of the legs 7 are exposed from both surfaces of the semiconductor package 50, the heat generated by the semiconductor element 1 can be efficiently dissipated.
In addition, the radiator 5 is composed of a radiator plate 6 and a plurality of legs 7,
Since each leg 7 is open and each leg 7 has a cutout 7c through which the resin 4 can pass, the fluidity of the resin 4 at the time of resin sealing is improved and the resin 4 is not filled. Can be prevented.

Next, a second embodiment of the present invention will be described with reference to FIGS.
Will be described with reference to. 5 is a sectional view of the semiconductor package, and FIG. 6 is a front view of the semiconductor package of FIG. 5 when viewed from the metal plate side. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the second embodiment, as in the first embodiment, the semiconductor element 1 is mounted on the film carrier 30, then inner lead bonding is performed, and the semiconductor element 1 is mounted on the heat dissipation plate 6 of the radiator 5, and an adhesive is applied. The heat sink 6 and the semiconductor element 1 are adhered to each other by using 8. The difference from the first embodiment is that a flat metal plate 9a is placed on the end 7a of the leg 7 of the radiator 5. Then, after mounting the metal plate 9a, sealing with the resin 4 is performed, and the semiconductor package 50 is obtained. Also here, since the leg portions 7 have elasticity, the height from the heat sink 6 to the metal plate 9a can be molded to be the same as the height of the semiconductor package 50.

According to the second embodiment constructed as described above, since the radiator plate 6 and the metal plate 9a are in close contact with the mold used for resin sealing, the radiator 5 has the same height as the semiconductor package 50. That is, the heat dissipation plate 6 does not float, and it is possible to prevent the resin 4 from flowing around the heat dissipation surface 6b of the heat dissipation plate 6 and the upper surface of the metal plate 9a. Then, the heat dissipation surface 6b of the heat dissipation plate 6 and the metal plate 9a
Since the and are exposed from both sides of the semiconductor package 50, the heat generated by the semiconductor element 1 can be efficiently dissipated. Further, since the radiator 5 is composed of the radiator plate 6 and the plurality of leg portions 7, the spaces between the leg portions 7 are open, and each leg portion 7 has the cutout portion 7c through which the resin 4 can pass, The fluidity of the resin 4 at the time of sealing is improved, and it is possible to prevent the resin 4 from being unfilled.

Next, a third embodiment of the present invention will be described with reference to FIGS.
Will be described with reference to. 7 is a sectional view of the semiconductor package, and FIG. 8 is a front view of the semiconductor package of FIG. 7 when viewed from the metal plate side. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the third embodiment, as in the second embodiment, the semiconductor element 1 is mounted on the film carrier 30, then inner lead bonding is performed, and the semiconductor element 1 is mounted on the heat dissipation plate 6 of the radiator 5, and an adhesive is applied. The heat sink 6 and the semiconductor element 1 are adhered to each other by using 8. The difference from the second embodiment is that a flat metal plate 9b having an open central portion is placed on the end portion 7a of the leg portion 7 of the radiator 5. After placing the metal plate 9b,
The semiconductor package 50 is obtained by performing sealing with the resin 4. Here again, since the leg portions 7 have elasticity, the height from the heat sink 6 to the metal plate 9b is determined by the semiconductor package 5
It can be molded to the same height as 0.

According to the third embodiment constructed as described above, the radiator plate 6 and the metal plate 9b are brought into close contact with the mold used for resin sealing in the same manner as described above. It becomes the same height as the package 50, and the heat sink 6 does not float,
Resin 4 on the heat radiation surface 6b of the heat radiation plate 6 and the upper surface of the metal plate 9b
Can be prevented from wrapping around. Then, the heat dissipation surface 6 of the heat dissipation plate 6
Since b and the metal plate 9b are exposed from both surfaces of the semiconductor package 50, the heat generated by the semiconductor element 1 can be efficiently radiated. Further, since the radiator 5 is composed of the radiator plate 6 and the plurality of leg portions 7, the spaces between the leg portions 7 are open, and each leg portion 7 has the cutout portion 7c through which the resin 4 can pass, The fluidity of the resin 4 at the time of sealing is improved, and it is possible to prevent the resin 4 from being unfilled. In particular, in the third embodiment, the metal plate 9b has an opening in the central portion, so that the fluidity of the resin 4 on the upper surface of the semiconductor element 1 is significantly improved.

In the above embodiments, since the leg portion 7 has elasticity, the height of the leg portion 7 before resin sealing is made higher than the thickness of the semiconductor package 50 to be molded.
When the leg portion 7 does not have elasticity, the height of the leg portion 7 before resin sealing may be set to substantially the same height as the thickness of the semiconductor package 50 to be molded. Therefore, as in the second or third embodiment, the metal plate 9a or 9 is formed on the end portion 7a of the leg portion 7.
When b is to be placed, the height of the metal plate 9a or 9b may be set on the assumption that it is substantially a part of the leg portion 7.
If the leg portion 7 does not have elasticity in the second or third embodiment, as shown in FIG. 5 or FIG.
Alternatively, a or 9b may be adhered to the end 7a of the leg 7 by using an adhesive 8 '.

The embodiments of the present invention have been described above.
The present invention is not limited to the above embodiments, and those having the structure intended by the present invention can obtain the same operational effect.

[0032]

As described above, according to the present invention,
A heat radiator having a larger area than the semiconductor element and covering the back surface of the semiconductor element and a plurality of leg portions is used, and each leg portion has substantially the same height as the semiconductor package or each leg has elasticity. By making the part higher than the semiconductor package, each leg is pressed by one mold in the upper and lower molds used for resin sealing, and the heat dissipation surface of the heat dissipation plate is pressed against the other mold. Therefore, the heat dissipation surface of the heat dissipation plate is in close contact with the mold, is not affected by the pressure of the resin, and the resin can be prevented from flowing around the exposed surface of the heat dissipation plate. For this reason, the heat dissipation of the heat generated by the semiconductor element can be extremely improved. Moreover, when the semiconductor package is mounted on the substrate, the resin is not interposed between the substrate and the heat sink, so that the thermal conductivity and electrical conductivity to the substrate are improved, and the heat dissipation and electrical stability are improved. It can be significantly improved. Furthermore, since the resin does not go around the exposed surface of the heat sink,
The appearance of semiconductor packages is good and the yield is high.

Further, a plurality of leg portions are provided apart from each other to open each leg portion, and a cutout portion is further provided in the leg portions to prevent the flow of resin during resin sealing. Therefore, the semiconductor package can be surely molded and can be sufficiently applied to a thin semiconductor package.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a semiconductor package that is a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a perspective view showing a state where a semiconductor element is mounted on the radiator of the first embodiment of the present invention.

FIG. 4 is an enlarged perspective view of a leg portion of the radiator.

FIG. 5 is a sectional view of a semiconductor package that is a second embodiment of the present invention.

6 is a front view of the semiconductor package of FIG. 5 when viewed from the metal plate side.

FIG. 7 is a sectional view of a semiconductor package that is a third embodiment of the present invention.

8 is a front view of the semiconductor package of FIG. 7 when viewed from the metal plate side.

FIG. 9 is a cross-sectional view of a conventional semiconductor package.

[Explanation of reference numerals] 1 semiconductor element 2 lead 3 film substrate 4 resin 5 radiator 6 radiator plate 6a heat absorbing surface 6b radiator surface 7 legs 7a end 7b support surface 7c cutout 8 adhesive 9a metal plate 9b ring-shaped metal Plate 30 Film carrier 50 Semiconductor package

Claims (9)

[Claims] 1. A heat radiator that radiates heat generated by a semiconductor element encapsulated in a resin in a semiconductor package, wherein the heat dissipation plate that has a larger area than the semiconductor element and covers a back surface of the semiconductor element is provided with the semiconductor package. A plurality of legs having substantially the same height as the thickness of the heat sink are spaced apart from each other. 2. The radiator according to claim 1, wherein the leg portion is provided with a cutout portion. 3. The radiator according to claim 1, wherein the leg portion includes an end portion having a supporting surface parallel to the heat radiation plate. 4. A radiator for radiating heat generated by a resin-sealed semiconductor element in a semiconductor package, wherein a radiator plate having an area larger than that of the semiconductor element and covering a back surface of the semiconductor element has a height of A radiator characterized in that a plurality of leg portions having a thickness higher than the thickness of the semiconductor package and having elasticity are provided separately from each other. 5. The radiator according to claim 4, wherein the leg portion is provided with a cutout portion. 6. The radiator according to claim 4, wherein the leg portion includes an end portion having a support surface parallel to the heat radiation plate. 7. A semiconductor package in which a semiconductor element is mounted on an insulating film substrate having a large number of conductive leads and resin-sealed, and a heat sink having an area larger than that of the semiconductor element, and the heat sink. A heat radiator including a plurality of legs provided apart from each other is provided, one surface of the heat dissipation plate is in contact with the back surface of the semiconductor element, and the other surface is exposed to one outer surface of the semiconductor package. At the same time, the end portions of the plurality of legs are exposed at the other outer surface of the semiconductor package. 8. The semiconductor package according to claim 7, wherein the leg portion of the radiator is provided with a cutout portion. 9. The semiconductor package according to claim 7, wherein a support surface parallel to the heat dissipation plate is provided at the end portion of the leg portion of the radiator.