JP3101038U - Heat sink for semiconductor package - Google Patents

Abstract

An object of the present invention is to provide a heat radiating plate for a semiconductor package that maintains a favorable heat radiating effect without a casting adhered to an upper surface of a protrusion formed on a metal plate as a heat radiating plate.
A metal plate having a central portion with a raised portion is provided with a raised portion at a substantially central position, and a plurality of guide openings formed on an outer peripheral wall of the raised portion. A support column 36 extending downward from the upper surface of the projection is formed in the plurality of guide openings to form a heat sink of a semiconductor package.
[Selection diagram] FIG.

Description

  The present invention relates to a semiconductor package technology, and more particularly, to a heat sink for a semiconductor package.

  With the development of semiconductor manufacturing technology, the density of integrated circuits is getting higher and higher, from those with as few as 10 transistors on an initial single chip to those with today's 10 million transistors. Became. In such a high-density transistor, the problem of heat radiation easily occurs, and the layout for that is important.

In a packaging process of an integrated circuit, for example, a package of a plastic ball grid array (Plastic Ball Grid Array) is provided with a metal heat radiating plate to enhance a heat radiating effect. A conventional heat sink and a semiconductor package having the heat sink are disclosed in FIGS. The heat radiating plate is a metal plate (10) having a protruding portion (12) formed in a central portion. The bottom surface of the metal plate (10) is provided on the substrate (16). The protrusion (12) has a space formed therein and is housed in the chip (18) and the lead (20), and the upper surface of the protrusion (12) is exposed to the outside.

When the pressure casting method is performed, the upper mold cavity is pressed against the upper surface of the projection to prevent the casting (22) from flowing between the mold cavity and the heat sink. As a result, the upper surface of the protruding portion (12) is exposed to the outside to enhance the heat radiation effect.

However, in the process of a package using a conventional embedded heat sink, a metal plate (10) is used in order to suppress the wire sweep phenomenon that occurs when the mold is pressed as shown in FIGS. A plurality of guide openings (14) are formed on the outer peripheral wall of the protrusion (12). However, such a configuration reduces the support of the radiator plate, and the casting (22) flows into the joint surface between the mold cavity and the radiator plate under the pressure of the press, and as shown in FIG. Castings easily adhere and affect the heat dissipation effect. Therefore, there is a demand in the industry for an improvement in the supporting force of the heat sink.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat sink for a semiconductor package which enhances the supporting force, prevents the casting from adhering to the upper surface of the heat sink, and enhances the heat dissipation effect.

Accordingly, the present inventor has conducted intensive studies in view of the drawbacks found in the prior art, and as a result, a metal plate having a raised portion formed at the center position, and having a raised portion substantially at the center position of the metal plate. Semiconductor package having a plurality of guide openings formed in an outer peripheral wall of the protrusion, and a support pillar extending downward from an upper surface of the protrusion in the plurality of guide openings. The present invention was completed based on the finding that the problem can be solved by the structure of the heat sink.

Hereinafter, this invention will be specifically described.
The heat radiating plate of a semiconductor package according to claim 1, wherein the heat radiating plate is a metal plate having a projecting portion formed at a central position, wherein the projecting portion is formed at a substantially central position of the metal plate, and A plurality of guide openings are formed in an outer peripheral wall of the portion, and a support pillar extending downward from an upper surface of the protrusion is formed in the plurality of guide openings.

According to a second aspect of the present invention, in the heat sink of the semiconductor package, the support column in the first aspect extends downward from an upper surface of the protruding portion and is connected to the metal plate.

  According to a third aspect of the present invention, there is provided a heat dissipation plate for a semiconductor package, wherein both ends of the support column in the first aspect are integrally connected to an upper surface of the protruding portion and an upper surface of a bottom portion of the metal plate, respectively.

According to a fourth aspect of the present invention, there is provided a heat dissipation plate for a semiconductor package, wherein one end of the support column in the first aspect extends downward from an upper surface of the protruding portion and is connected to a common plane at the bottom of the metal plate.

  The semiconductor package of the present invention has an advantage that the casting does not adhere to the upper surface of the protruding portion formed on the metal plate serving as the heat radiating plate, the preferable heat radiating effect is maintained, and the appearance of the product is not impaired. .

As disclosed in FIGS. 3 to 5, the heat sink according to the present invention is a metal plate (30) having a protrusion (32) formed at a center position, and the metal plate (30) is packaged. It is provided on a substrate (38). A chip (40) and a lead (32) are housed in the internal space of the protrusion (32), and a plurality of guide openings (34) are formed in the outer peripheral wall of the protrusion (32). The plurality of guide openings (34) have an effect of suppressing a wire sweep phenomenon that occurs in pressure casting.

  In addition, as disclosed in FIG. 5A, a support pillar (36) extending from the upper surface of the protrusion (32) to the upper surface of the bottom of the metal plate (30) is integrally formed in the guide opening (34). .

  When pressure casting is performed, the upper mold cavity is closely pressed against the upper surface of the projection (32), and the casting (44) flows into the pressure contact surface between the upper mold cavity and the heat sink, and the projection ( 32) is prevented from adhering to the upper surface. That is, the adhesion of the casting (44) can prevent the heat radiation effect and the influence on the appearance of the product. When performing pressure casting, the casting (44) is pushed between the upper mold cavity and the heat sink by the pressure of the press, but the heat sink is deformed by the pressure of the press by the support force of the support column (36). It is possible to prevent the upper surface of the protrusion (32) from being covered with the casting (44) without any problem. Therefore, a decrease in the heat radiation effect can be suppressed.

  6 and 6A disclose a second embodiment. The heat radiating plate according to the second embodiment is a metal plate (30) having a projection (32) formed at a center position, and the metal plate (30) is provided on a substrate (38) to be packaged. . A chip (40) and a lead (32) are housed in the internal space of the projection (32), and a plurality of guide openings are formed in the outer peripheral wall of the projection (32). The plurality of guide openings (34) have an effect of suppressing a wire sweep phenomenon that occurs in pressure casting.

  In addition, a support column (46) extending from the upper surface of the projection (32) to the common plane at the bottom of the metal plate (30) is integrally formed in the guide opening to obtain a supporting force.

  When performing pressure casting, the mold cavity of the upper mold is closely pressed against the upper surface of the projection (32). In this case, it is possible to prevent the casting (44) from covering the upper surface of the protrusion (32) without deforming the supporting force radiation plate of the support column (46) due to the pressure of the press. Therefore, a decrease in the heat radiation effect is suppressed, and the appearance of the product is not impaired.

  The above is a preferred embodiment of the present invention, and does not limit the scope of implementation of the present invention. Therefore, any modification or change that can be made by those skilled in the art, which is made in the spirit of the present invention and has an equivalent effect on the present invention, belongs to the claims of the present invention. Shall be.

It is the perspective view which showed the heat sink in which the conventional guide opening was formed. It is an explanatory view showing a package structure using a conventional heat sink. FIG. 3 is a partial enlarged view of FIG. 2. FIG. 4 is a perspective view showing a heat sink according to the present invention. (Example 1) FIG. 4 is a plan view of a heat sink disclosed in FIG. 3. (Example 1) FIG. 4 is an explanatory view showing a package structure using a heat sink according to the present invention. (Example 1) FIG. 6 is a partially enlarged view of FIG. 5. (Example 1) FIG. 11 is an explanatory diagram showing a package structure according to another embodiment. (Example 2) FIG. 7 is a partially enlarged view of FIG. 6. (Example 2)

Explanation of reference numerals

Reference Signs List 10 Metal plate 12, 32 Projection 14, 34 Guide opening 16 Substrate 18 Chip 20, 42 Lead 22, 44 Casting 30 Metal plate 36, 46 Support post 40 Chip

Claims (4)

A metal plate having a projecting portion formed at a central position, wherein a projecting portion is formed at a substantially central position of the metal plate, and a plurality of guide openings are formed in an outer peripheral wall of the projecting portion. A heat sink for a semiconductor package, wherein support pillars extending downward from an upper surface of the protrusion are formed in the plurality of guide openings. The heat sink of claim 1, wherein the support pillar extends downward from an upper surface of the protrusion and is connected to the metal plate. 2. The heat sink of claim 1, wherein both ends of the support pillar are integrally formed by being connected to an upper surface of the protrusion and an upper surface of a bottom of the metal plate, respectively. 3. The heat sink of claim 1, wherein one end of the support post extends downward from an upper surface of the protrusion and is connected to a common plane at a bottom of the metal plate.

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