TWI615930B - Heat sink and chip package having the same - Google Patents

Abstract

A heat sink includes a heat sink body and a plurality of extensions. The heat dissipation body has a heat dissipation surface, at least one first groove on the heat dissipation surface, an annular protrusion on the heat dissipation surface, and at least one second groove on the heat dissipation surface. The annular protrusion is located between the first groove and the second groove. The annular protrusion surrounds at least one groove. The plurality of extending portions respectively extend outward from an edge of the heat dissipation body. Each extension has an opening. In addition, a chip package including the heat sink is also proposed.

Description

Radiator and chip package with radiator

The present invention relates to a heat sink, and more particularly, to a heat sink suitable for use in a chip package.

Generally speaking, when the chip is operating, a large amount of thermal energy is generated. If thermal energy cannot be dissipated and is continuously accumulated in the wafer, the temperature of the wafer will continue to rise. As a result, the chip may suffer from performance degradation or shortened service life due to overheating. In severe cases, it may even cause permanent damage. In order to prevent the wafer from overheating causing temporary or permanent failure, a heat sink is usually required to reduce the operating temperature of the wafer, so that the wafer can operate normally.

In the manufacturing process of a chip package with a heat sink, the heat sink is usually arranged on the circuit carrier board, and the chip is located between the heat sink and the circuit carrier board, then placed together in a mold, and then the molten packaging gel is placed. For example, Epoxy Molding Compound (EMC) is injected into the mold, so that the encapsulation gel covers the circuit carrier board, the chip and part of the heat sink. Next, the encapsulant is cooled and solidified to form an encapsulation layer.

However, because the flow rate or flow rate of the mold flow is not easy to control, or because of the disturbance caused during the injection process, the packaging gel may partially cover the heat dissipation surface of the heat sink, thereby causing defects in the appearance of the chip package and causing The heat dissipation efficiency of the chip package cannot be effectively improved. Therefore, how to further improve the heat dissipation efficiency of the chip package has become an urgent problem to be solved.

The invention provides a heat dissipating member and a chip package with a heat dissipating member, which have good manufacturing yield and can improve the heat dissipation efficiency of the chip package.

An embodiment of the present invention provides a heat dissipating member, which includes a heat dissipating body and a plurality of extending portions. The heat-dissipating body has a heat-dissipating surface, at least one first groove on the heat-dissipating surface, an annular protrusion on the heat-dissipating surface, and at least one second groove on the heat-dissipating surface, wherein the annular protrusion is located in the first groove And the second groove, and the annular protrusion surrounds the at least one first groove. The plurality of extension portions respectively extend outward from an edge of the heat dissipation body, and each extension portion has an opening.

Another embodiment of the present invention provides a chip package, which includes a circuit carrier board, a chip, a heat sink, and a packaging layer. The chip is disposed on the circuit carrier board and is electrically connected to the circuit carrier board. The heat sink is arranged on the circuit carrier board so that the chip is located between the heat dissipation body and the circuit carrier board. The encapsulation layer covers the circuit carrier board, the chip, and the heat sink.

In order to make the above features and advantages of the present invention more comprehensible, embodiments are hereinafter described in detail with reference to the accompanying drawings.

FIG. 1A is a schematic top view of a heat sink according to a first embodiment of the present invention. FIG. 1B is an enlarged view of the R1 region in FIG. 1A. Fig. 1C is a schematic cross-sectional view taken along the line A-A 'in Fig. 1B. Please refer to FIG. 1A to FIG. 1C first. The heat sink 100 of this embodiment includes a heat sink body 110 and a plurality of extension portions 130. The heat dissipation body 110 has a heat dissipation surface 110a, a first groove 114 on the heat dissipation surface 110a, an annular protrusion 112 on the heat dissipation surface 110a, and a second groove 116 on the heat dissipation surface 110a. The annular protrusion 112 is located between the first groove 114 and the second groove 116, and the annular protrusion 112 surrounds the first groove 114. The plurality of extension portions 130 respectively extend outward from an edge of the heat dissipation body 110, and each of the extension portions 130 has an opening 130 a.

The heat sink 100 is made by, for example, stamping a thin metal plate by a stamping process. In some embodiments, before the stamping process is performed, the metal sheet may be pre-cut into a contour and size suitable for forming the heat sink 100, and then the metal sheet having a specific contour and size is correspondingly extruded through the stamping process. Or bent to form the heat sink 100. In some embodiments, the metal sheet can be cut into a contour and a size suitable for forming the heat sink 100 through a water jet cutter technology or a laser cutting technology. In other embodiments, the cutting of the metal sheet may be performed in a stamping process. In this embodiment, the heat dissipating body 110 and the extending portion 130 of the heat dissipating member 100 are integrally formed, and are, for example, the same metal material, but the present invention is not limited thereto.

In this embodiment, the heat dissipation body 110 of the heat sink 100 is a circular plate-shaped body, the first groove 114 is an annular groove, and the second groove 116 is an annular groove. The annular protrusion 112 is located on the periphery of the heat dissipation body 110 and surrounds the annular first groove 114. The first groove 114 is adjacent to the annular protrusion 112, so that the first sidewall 112 a 1 of the annular protrusion 112 is aligned with the groove sidewall 114 a of the first groove 114. The second groove 116 is adjacent to the annular protrusion 112, so that the second sidewall 112 a 2 of the annular protrusion 112 is aligned with the groove sidewall 116 a of the second groove 116. The heat dissipation surface 110 a surrounded by the first groove 114 is, for example, a flat surface. In detail, since the heat sink 100 of this embodiment is made by a stamping process, an additional thin metal plate is needed to form the first groove 114 and the second groove 116. Therefore, the metal material subjected to the additional pressing on the heat dissipation surface 110a can correspondingly form the annular protrusion 112 between the first groove 114 and the second groove 116, so as to reduce defects formed by the heat dissipation surface 110a during the stamping process. (Such as burrs, wavy patterns, or tears). In this way, the heat dissipation member 100 has a good manufacturing yield, and the heat dissipation surface 110a surrounded by the first groove 114 and / or the bottom surface on the opposite side of the heat dissipation surface 110a may be flat, so that the heat dissipation member 100 has good heat dissipation. effectiveness.

In this embodiment, the heat sink 100 includes four extensions 130, and the four extensions 130 are respectively located at the edges of the heat sink 110, and are extended and bent outwardly from the edges of the heat sink 110 to be formed under the heat sink 100. An accommodation space. In this way, the accommodating space formed can accommodate the chip 26 (shown in FIG. 2A) in the chip package 20 (shown in FIG. 2A). Each extension 130 has an opening 130a, and at least one opening 130a in the heat sink 100 allows a mold flow to pass through. In this way, in the subsequent injection molding process, a molten encapsulating gel (for example, epoxy molding resin) can be filled into the accommodation space through at least one of the openings 130a, thereby covering the circuit carrier board. 22 (shown in FIG. 2A), wafer 26 (shown in FIG. 2A), and a part of the heat sink 100. Next, the encapsulant is cooled and solidified to form an encapsulation layer 24 (shown in FIG. 2A).

The extension portion 130 includes a first inclined portion 132, a first connecting portion 134, a second inclined portion 136, and a second connecting portion 138. It is worth noting that, in the schematic cross-sectional view of FIG. 1C, the first inclined portion 132, the first connecting portion 134, the second inclined portion 136, and a portion of the second connecting portion 138 of the extension portion 130 do not appear in FIG. 1B On the section line AA '. However, in FIG. 1C, the projection positions of the first inclined portion 132, the first connection portion 134, the second inclined portion 136, and a portion of the second connection portion 138 of the extension portion 130 are still shown in dotted lines to indicate the position of the projection portion. Correspondence.

In this embodiment, the heat sink 100 is connected to the circuit substrate 22 (shown in FIG. 2A) through the second connection portion 138 of the extension portion 130. Specifically, in an embodiment, the heat sink 100 and the circuit substrate 22 (shown in FIG. 2A) may include, for example, an adhesive layer (not shown), so that the second connection portion 138 and the circuit substrate 22 (shown in FIG. 2A) are connected to each other by an adhesive layer. In another feasible embodiment, the second connection portion 138 may have a tenon, for example, and the circuit carrier board 22 (shown in FIG. 2A) may have a card slot corresponding to the tenon, so that the second connection The portion 138 and the circuit board 22 (shown in FIG. 2A) can be engaged with each other. In another feasible embodiment, the surface of the circuit carrier board 22 (shown in FIG. 2A) may have a recess corresponding to the second connection portion 138 so that the second connection portion 138 can be directly placed on the circuit carrier board 22. (Shown in Figure 2A).

In this embodiment, the second inclined portion 136 is connected to the second connecting portion 138, the first connecting portion 134 is connected to the second inclined portion 136, and the second inclined portion 136 is located at the first connecting portion 134 and the second connecting portion 138. between. In this way, the heat dissipation body 110, the first connection portion 134 of the extension portion 130, and the second inclined portion 136 of the extension portion 130 can form a container for accommodating the chip 26 (shown in FIG. 2A) below the heat dissipation body 110. Home space. In one embodiment, the second inclined portion 136 has a proper distance between the heat dissipation body 110 and the chip 26 (shown in FIG. 2A) so as to connect the chip 26 (shown in FIG. 2A) and the circuit board 22 ( The plurality of wires 26 a (shown in FIG. 2A) (shown in FIG. 2A) between them are not in contact with the heat dissipation body 110. The first connecting portion 134 extends outward from the edge of the heat dissipation body 110 to form an accommodating space that can receive the chip 26 (shown in FIG. 2A) with the second inclined portion 136. In another feasible embodiment, the extending portion 130 may have a plurality of second inclined portions 136 and / or a plurality of first connecting portions 134 to form a receiving space capable of receiving the wafer 26 (shown in FIG. 2A).

In other feasible embodiments, the chip 26 and the circuit substrate 22 may be electrically connected to each other through conductive bumps. In other words, the chip 26 can be disposed on the circuit carrier board 22 through a flip-chip technology, and is electrically connected to the circuit carrier board 22.

In this embodiment, the first inclined portion 132 of the extension portion 130 is connected to the heat dissipation body 110, and the first inclined portion 132 is connected to the first connection portion 134, wherein the first inclined portion 132 is located on the heat dissipation body 110 and the first connection portion 134. And the four extending portions 130 of the heat sink 100 are connected to each other through the respective first connecting portions 134, but the present invention is not limited thereto. In a feasible embodiment, the four extending portions 130 of the heat sink 100 can be separated from each other, and the first inclined portion 132 of each extending portion 130 is connected to the heat dissipation body 110.

FIG. 2A is a schematic cross-sectional view of a chip package according to an embodiment of the present invention, and FIG. 2B is an enlarged view of an R2 region in FIG. 2A. Please refer to FIGS. 2A to 2B first. The chip package 20 of this embodiment includes a circuit carrier board 22, a chip 26, a heat sink 100, and a packaging layer 24. The chip 26 is disposed on the circuit carrier board 22 and is electrically connected to the circuit carrier board 22. The heat sink 100 is disposed on the circuit carrier board 22 so that the chip 26 is located between the heat dissipation body 110 and the circuit carrier board 22. The packaging layer 24 covers the circuit substrate 22, the chip 26, and the heat sink 100.

In this embodiment, the circuit carrier board 22 is, for example, a printed circuit board (PCB) with a single-layer circuit, a printed circuit board with a multi-layer circuit, or a substrate with a redistribution layer. The chip 26 is, for example, attached to the circuit carrier board 22 with a wafer attaching film (not shown), and the chip 26 is electrically connected to the circuit carrier board 22 by a plurality of wires 26 a by wire bonding. In some embodiments, the chip package 20 may further include a plurality of conductive terminals 28, wherein the conductive terminals 28 are disposed on the circuit carrier board 22, and the conductive terminals 28 and the chip 26 are located on two sides of the circuit carrier board 22, respectively. On the opposite surface. In addition, the conductive terminals 28 are, for example, arrayed solder balls, bumps, conductive pillars, or a combination thereof, so that the chip 26 passes the circuit carrier board 22 and the conductive terminals 28 and Other components are electrically connected.

In this embodiment, the heat sink 100 is disposed on the circuit carrier board 22, and the chip 26 is located in an accommodation space formed by the heat sink body 110 and the extension 130, so that the chip 26 is positioned between the heat sink body 110 and the circuit carrier board 22. between. The heat dissipation body 110 of the heat sink 100 covers the wafer 26, and the area of the heat dissipation surface 110 a 1 surrounded by the first groove 114 is larger than the area of the active surface 26 b of the wafer 26. In this way, the heat sink 100 has a large heat dispersion area, so that the heat generated when the chip 26 operates can be dissipated from the active surface 26b of the chip 26 to the heat dissipation surface 110a1 surrounded by the first groove 114. The thermal energy is dissipated by the heat sink 100 so that the chip package 20 has good heat dissipation efficiency, but the present invention is not limited thereto.

The encapsulation layer 24 includes a first encapsulation portion 24 a and a second encapsulation portion 24 b. The first encapsulation portion 24 a is located on the circuit carrier board 22 to cover the wafer 26, the first encapsulation portion 24 a is covered by the heat sink 100, and the second package The portion 24 b covers the extension portion 130 of the heat sink 100, and the second package portion 24 b is connected to the first package portion 24 a through the opening 130 a of the extension portion 130. In the injection molding process of the chip package 20, the heat sink 100 may be disposed on the circuit carrier board 22, and the wafer 26 may be located between the heat sink 100 and the circuit carrier board 22 and placed together in a mold. Next, the molten encapsulant is injected into the mold. In the mold, the mold formed by the molten encapsulating gel flows through at least one opening 130a and the lateral space in the heat sink 100 and enters the accommodation space formed by the heat sink body 110, the second inclined portion 136, and the first connection portion 134. Inside, so that the packaging gel covers the circuit board 22, the chip 26, and a part of the heat sink 100. In addition, the molten encapsulating gel can flow out of the accommodating space through the remaining openings 130a, so that a part of the encapsulating gel covers the extension portion 130. Then, the molten encapsulating colloid is cooled and solidified to form an encapsulating layer 24. In this way, the packaging colloid in the accommodating space will form a first packaging portion 24a of the packaging layer 24 after curing, and the packaging gel outside the accommodating space will form a second package of the packaging layer 24 after curing.部 24b. 24b. The second package portion 24 b can be connected to the first package portion 24 a through the opening 130 a of the extension portion 130 and covers the extension portion 130 of the heat sink 100.

Since the annular protrusion 112 on the heat dissipation surface 110a can be attached to the mold, the annular protrusion 112 can block the molten encapsulant during the injection molding process. In this way, the molten encapsulation gel will not cover a part of the heat dissipation surface 110 a 1 surrounded by the annular protrusion 112, so that the encapsulation layer 24 formed by the cured encapsulation gel will not affect the heat dissipation function of the heat sink 100.

2C and 2D are schematic partial cross-sectional views of a chip package according to another embodiment of the present invention, wherein FIG. 2C is a partial cross-sectional schematic view of a chip package 20 'according to another embodiment of the present invention, and the chip package is shown in FIG. 2C The partial area shown in FIG. 20 ′ corresponds to the R2 area shown in FIG. 2B for the chip package 20, FIG. 2D is an enlarged view of the R3 area in FIG. 2C, and the wafer of another embodiment in FIGS. 2C and 2D The package 20 ′ is similar to the chip package 20 of FIGS. 2A and 2B, and similar components are denoted by the same reference numerals and have similar functions, and descriptions thereof are omitted. The main difference between the chip package 20 and the chip package 20 'is that the second groove 116 can limit a part of the molten packaging gel, and even if the molten packaging gel passes over the annular protrusion 112, it can still be located in the heat dissipation body. The first groove 114 of 110 limits the molten encapsulant to the first groove 114. In this way, the molten packaging gel will not cover the area of the heat dissipation surface 110a1 surrounded by the annular protrusion 112, and the packaging layer 24 '(including the first packaging portion 24a' and the second packaging portion) formed by the cured packaging gel 24b 'and the redundant package portion 24c') do not affect the heat dissipation function of the heat sink 100.

The heat sink 100 used in the chip package 20 may have other designs. The changes of the heat sink 100 will be described below with reference to FIGS. 3 to 5.

3 is a schematic partial top view of a heat sink according to a second embodiment of the present invention. Please refer to FIG. 3. In this embodiment, the heat dissipating member 300 is similar to the heat dissipating member 100, and similar components are denoted by the same reference numerals, and have similar functions, and descriptions thereof are omitted. The main difference between the heat dissipating member 300 and the heat dissipating member 100 is that the heat dissipating body 310 of the heat dissipating member 300 has an annular protrusion 312, a plurality of first grooves 314 and a plurality of second grooves 316. The annular protrusion 312 is located on the periphery of the heat dissipation body 310 and surrounds the plurality of first grooves 314. The plurality of second grooves 316 are a plurality of arc-shaped grooves separated from each other, wherein the second grooves 316 are distributed corresponding to the openings 130 a of the extension portion 130. The plurality of first grooves 314 are a plurality of arc-shaped grooves separated from each other, wherein the first grooves 314 are distributed corresponding to the openings 130 a of the extension portion 130. In this way, even if the encapsulating gel after passing the annular protrusion 312 has different directions of flow, it can still be limited to the first groove 314.

In an embodiment, the plurality of first grooves 314 are a plurality of arc-shaped grooves separated from each other, wherein the first grooves 314 are distributed corresponding to the openings 130 a of the extension 130, and the arc-shaped length of the first grooves 314 W1 is larger than the maximum width W2 of the corresponding opening 130a. In this way, even if the encapsulating gel after passing the annular protrusion 312 has different directions of flow, it can still be limited to the first groove 314.

FIG. 4 is a schematic partial top view of a heat sink according to a third embodiment of the present invention. Please refer to FIG. 4. In this embodiment, the heat dissipating member 400 is similar to the heat dissipating member 100, and similar components are denoted by the same reference numerals, and have similar functions, and descriptions thereof are omitted. The main difference between the heat sink 400 and the heat sink 100 is that the heat dissipation body 410 of the heat sink 400 has an annular protrusion 412, an annular first groove 414, and a plurality of second grooves 416, and the annular protrusion 412 is located at Between the first groove 414 and the second groove 416. The plurality of second grooves 416 are a plurality of arc-shaped grooves separated from each other, wherein the second grooves 416 are distributed corresponding to the openings 130 a of the extension portion 130. The annular protrusion 412 is located on the periphery of the heat dissipation body 410 and surrounds the first groove 414. In this way, even if the molten encapsulating gel passes over the annular protrusion 412, the molten encapsulating gel can be limited to the first recess 414 by the first recess in the heat dissipation body 410.

5 is a schematic partial top view of a heat sink according to a fourth embodiment of the present invention. Please refer to FIG. 5. In this embodiment, the heat dissipating member 500 is similar to the heat dissipating member 300, and similar components are denoted by the same reference numerals, and have similar functions, and descriptions thereof are omitted. The main difference between the heat dissipating member 500 and the heat dissipating member 300 is that the heat dissipating body 510 of the heat dissipating member 500 has an annular protrusion 512, a plurality of first grooves 514, and an annular second groove 516, and the annular protrusion 512 is located at Between the first groove 514 and the second groove 516. The plurality of first grooves 514 are a plurality of arc-shaped grooves separated from each other, wherein the first grooves 514 are distributed corresponding to the openings 130a of the extension 130, and the arc-shaped length of the first grooves 514 is larger than that of the corresponding openings 130a. The maximum width. The annular protrusion 512 is located on the periphery of the heat dissipation body 510 and surrounds the first groove 514. In this way, even if the encapsulating gel after passing the annular protrusion 512 has different directions of flow, it can still be limited to the first groove 514.

In summary, the heat sink of the present invention has good manufacturing yield and good heat dissipation efficiency. In addition, the chip package having the heat sink of the present invention has good heat dissipation efficiency.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some modifications and retouching without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the attached patent application.

100, 300, 400, 500‧‧‧ heat sink

110, 310, 410, 510‧‧‧

110a, 110a1, 110a2, 310a, 410a, 510a‧‧‧

112, 312, 412, 512‧‧‧ annular protrusion

112a1‧‧‧First sidewall

112a2‧‧‧Second sidewall

114, 314, 414, 514‧‧‧ first groove

116, 316, 416, 516‧‧‧ second groove

114a, 116a

130‧‧‧ extension

130a‧‧‧ opening

132‧‧‧first slope

134‧‧‧First connection

136‧‧‧Second Inclined Section

138‧‧‧Second connection section

W1‧‧‧ length

W2‧‧‧Width

20, 20’‧‧‧ Chip Package

22‧‧‧line carrier board

24, 24'‧‧‧ Encapsulation

24a, 24a'‧‧‧ first package department

24b, 24b'‧‧‧Second package department

24c'‧‧‧Excessive Packaging Department

26‧‧‧Chip

26a‧‧‧Wire

26b‧‧‧ active face

28‧‧‧Conductive terminal

R1, R2, R3 ‧‧‧ area

FIG. 1A is a schematic top view of a heat sink according to a first embodiment of the present invention. FIG. 1B is an enlarged view of the R1 region in FIG. 1A. Fig. 1C is a schematic cross-sectional view taken along the line A-A 'in Fig. 1B. FIG. 2A is a schematic cross-sectional view of a chip package according to an embodiment of the present invention. FIG. 2B is an enlarged view of the R2 region in FIG. 2A. 2C is a schematic partial cross-sectional view of a chip package according to another embodiment of the present invention. FIG. 2D is an enlarged view of the R3 region in FIG. 2C. 3 is a schematic partial top view of a heat sink according to a second embodiment of the present invention. FIG. 4 is a schematic partial top view of a heat sink according to a third embodiment of the present invention. 5 is a schematic partial top view of a heat sink according to a fourth embodiment of the present invention.

100‧‧‧ heat sink

110‧‧‧cooling body

112‧‧‧ annular protrusion

114‧‧‧first groove

116‧‧‧Second groove

130‧‧‧ extension

130a‧‧‧ opening

132‧‧‧first slope

134‧‧‧First connection

136‧‧‧Second Inclined Section

138‧‧‧Second connection section

R1‧‧‧ area

Claims (10)

A heat-dissipating member includes a heat-dissipating body having a heat-dissipating surface, at least one first groove on the heat-dissipating surface, an annular protrusion on the heat-dissipating surface, and at least one second recess on the heat-dissipating surface. A groove, wherein the annular protrusion is located between the at least one first groove and the at least one second groove, and the annular protrusion surrounds the at least one first groove; and a plurality of extensions respectively from the An edge of the heat dissipation body extends outward, and each of the extension portions has an opening. The heat sink according to item 1 of the patent application scope, wherein the heat sink body comprises a circular plate-shaped body. According to the first aspect of the patent application, the at least one first groove includes a plurality of first arc-shaped grooves separated from each other, and the first arc-shaped grooves correspond to the openings. According to the third aspect of the patent application scope, the length of each of the first arc-shaped grooves is greater than the width of the corresponding opening. The heat sink according to item 1 of the patent application, wherein the at least one first groove includes at least one first annular groove. According to the first aspect of the patent application, the at least one second groove includes a plurality of second arc-shaped grooves separated from each other, and the second arc-shaped grooves correspond to the openings. As described in item 6 of the patent application scope, the length of each of the first arc-shaped grooves is greater than the width of the corresponding opening. The heat sink according to item 1 of the patent application, wherein the at least one second groove includes at least one second annular groove. A chip package includes: a circuit carrier board; a chip disposed on the circuit carrier board and electrically connected to the circuit carrier board; a heat sink according to claim 1, the heat sink being arranged on the circuit A carrier board so that the chip is located between the heat dissipating body and the circuit carrier board; and a packaging layer covering the circuit carrier board, the chip and the heat sink. The chip package according to item 9 of the scope of patent application, wherein the packaging layer includes: a first package portion located on the circuit carrier board to cover the chip, and the first package portion is covered by the heat sink; And a second packaging portion covering the extension portions, and the second packaging portion is connected to the first packaging portion through the openings.