TWI587550B - A heat sink and use the heat sink package - Google Patents

Description

Heat sink and package structure using the same

The present invention relates to a heat sink and a package structure using the same, and more particularly to a heat sink and package structure used in wafer packaging.

With the advancement of technology and the development of industry, today's electronic products are changing with each passing day. Under the demand of human beings to pursue science and technology, electronic products have already developed towards refined and thin-form production technology.

However, regardless of the refined or thinned electronic products, the internal electronic chip generates a large amount of heat during operation. Therefore, as the internal circuit integration of the IC chip continues to rise, how to heat efficiently and quickly The discharge has become an important issue in the IC chip packaging process, so metal heat sinks with high thermal conductivity characteristics are often used in the packaging process.

In addition, in recent years, smart phones and tablets have flourished, and the functions of mobile phones and tablets have become stronger and stronger, but the design of the body has become thinner and lighter. IC design companies must consider simplifying the chip in the early stage of mobile phone or tablet chip design. The configuration space, but even if the chip has been designed to reduce the height and save the configuration space, without the proper heat sink to match, it is actually unable to achieve the purpose of streamlining the space.

The reason is that the present inventors have felt that the heat-dissipating components of the wafers of the aforementioned electronic products are missing, and then intensively and actively researched and developed a heat sink which is required to meet the actual conditions.

In view of the above, it is an object of the present invention to provide a Heat sinks to meet the needs of wafers for thin and light electronic products.

The heat sink of the present invention comprises a central portion, a plurality of support bottoms, and a plurality of connecting portions, wherein the central portion has a first reference surface and a second reference surface opposite to the first reference surface, the first A thickness D is defined between a reference surface and the second reference surface, the plurality of support bottoms are located at an edge of the central portion and are concave with respect to the first reference surface, and each support bottom has a support bottom surface. A height H is defined between the bottom surface of the support and the first reference surface. The height H is greater than the thickness D. The plurality of connecting portions respectively connect the central portion and the supporting bottom portion corresponding to each other.

Another object of the present invention is to provide a package structure including a substrate, a flip chip, a heat sink, and an encapsulant, wherein the flip chip is disposed on the substrate, and the heat sink includes a central portion, a plurality of support bottoms, and a plurality of connecting portions, wherein the central portion has a first reference surface and a second reference surface opposite to the first reference surface, the first reference surface and the second portion A thickness D is defined between the reference surfaces, the plurality of support bottoms are located at an edge of the central portion and are concave with respect to the first reference surface, and each support bottom has a support bottom surface, the support bottom surface and the first A height H is defined between the reference planes, and the height H is greater than the thickness D. The plurality of connecting portions are respectively connected to the central portion and the supporting bottom portion corresponding to each other, and the encapsulant adheres to the flip chip and at least a portion thereof a substrate and at least a portion of the heat sink.

Yet another technical means of the present invention is that the number of the plurality of support bottoms is four, and is located symmetrically on four sides or four corners of the central portion.

According to still another aspect of the present invention, the heat sink further includes a plurality of end portions, each end portion being lifted by a corresponding support bottom toward the first reference surface.

Another technical means of the present invention is that the central portion has at least one opening.

According to still another aspect of the present invention, the second reference surface of the central portion and the support bottom surface of the plurality of support bottoms are both rough surfaces.

The beneficial effect of the invention is that a plurality of support bottoms are formed by the edge of the central portion, so that the proportion of the bottom of the support relative to the heat sink is minimized, and the central portion can generate a maximum range of heat dissipation utilization area. In order to effectively meet the needs of thin and light wafers, the goal of streamlining space is achieved.

10‧‧‧ Heat sink

12‧‧‧ Central Department

14‧‧‧Support bottom

16‧‧‧Connecting Department

18‧‧‧End

20‧‧‧ first datum

22‧‧‧second datum

24‧‧‧Support bottom

26‧‧‧ openings

28‧‧‧Substrate

30‧‧‧Flip chip

34‧‧‧Package colloid

1 is a top plan view showing a preferred embodiment of the heat sink of the present invention; FIG. 2 is a perspective view showing a three-dimensional view of the preferred embodiment; FIG. 3 is a side cross-sectional view, and FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Figure 4 is a partial side elevational cross-sectional view showing the state of a plurality of heat sink stacks; and Figure 5 is a side cross-sectional view showing a preferred embodiment of the package structure of the present invention.

The detailed description of the preferred embodiments of the present invention will be apparent from the detailed description of the preferred embodiments.

Referring to Figures 1, 2 and 3, a preferred embodiment of the heat sink 10 of the present invention comprises a central portion 12, a plurality of support bottoms 14, and a plurality of connecting portions 16, wherein the central portion 12 has a first reference surface 20 A thickness D is defined between the first reference surface 20 and the second reference surface 22 opposite to the second reference surface 22 of the first reference surface 20, and the plurality of support bottoms 14 are located at the central portion 12. Edge and relative to the first reference surface 20 Each of the support bottoms 14 has a support bottom surface 24, and a height H is defined between the support bottom surface 24 and the first reference surface 20, the height H is greater than the thickness D, and the plurality of connection portions 16 are respectively Connecting the central portion 12 to the supporting bottom portion 14 corresponding to each other, wherein the central portion 12 has at least one opening 26, and the second reference surface 22 of the central portion 12 and the supporting bottom surface 24 of the plurality of supporting bottom portions 14 are It is a rough surface, and the first reference surface 20 of the center portion 12 is a smooth surface.

In the present embodiment, the heat sink 10 adopts a square shape, and the number of the plurality of support bottoms 14 is four, and is located symmetrically on four sides or four corners of the center portion 12. Of course, in addition to being disposed at four or four corners, it may be disposed on two opposite sides or two opposite sides of the square. In this way, the central portion 12 can also be compared with the majority. The support bottoms 14 form an elevated state such that the wafer 30 or electronic components are hidden in the elevated space below the central portion 12, and since the plurality of support bottoms 14 are symmetrical with each other, The heat sink 10 can obtain a stable supporting effect.

In addition, the heat sink 10 further includes a plurality of end portions, each of which is lifted by the corresponding support bottom portion 14 toward the first reference surface 20, and thus, as shown in FIG. When the heat sinks 10 are manufactured and stacked on each other for storage or transportation, each of the heat sinks 10 will form a gap with the adjacent heat sink 10 at the end portion because each end portion is in a lifted state. First, when the line operator or the automated arm picks up the heat sink 10, it can be inserted from the slit, and the upper heat sink 10 can be taken separately, and it is not easy to get a plurality of stacked heat sinks 10 at a time. , can effectively save work hours.

Referring to FIG. 5, the present invention further provides a package structure using the heat sink 10, the package structure includes a substrate 28, a flip chip 30, and an encapsulant 34. The flip chip 30 is disposed on the substrate. At 28, the encapsulant 34 adheres the flip chip 30 and at least a portion of the substrate 28 to at least a portion of the heat sink 10.

The heat sink 10 includes a central portion 12, a plurality of support bottom portions 14, and a plurality of connecting portions 16, which are designed as shown in the foregoing FIGS. 1-3, and the detailed design of each portion will not be described herein.

The assembly process of the package structure is as follows: First, each connection point of the flip chip 30 is formed into a bump, and then the flip chip 30 is turned over to directly connect the bump to the substrate 28. Then, the heat sink 10 is attached to the substrate 28 and the flip chip 30 is accommodated, and then the package is assembled. The assembled state is as shown in FIG. 5, and the package adhesive 34 is adhered to the flip chip. 30 and at least a portion of the substrate 28 and at least a portion of the heat sink 10.

In the present embodiment, the central portion 12 has at least one opening 26. The purpose of the opening 26 is mainly for the orientation recognition and when the encapsulant 34 is adhered between the heat sink 10 and the flip chip 30, such as In the case where there is too much glue, it can overflow from the opening 26, instead of generating an overflow from the periphery of the flip chip 30, thereby controlling the overflow position and the amount of overflow.

In addition, since the heat sink 10 has a square shape and has no clear directivity, the opening 26 opened by the center portion 12 is eccentric rather than centered, and a clear directivity is generated. When the heat sink 10 is assembled, it can have a clear alignment, which is advantageous for assembly accuracy.

Moreover, the second reference surface 22 of the central portion 12 and the supporting bottom surface 24 of the plurality of supporting bottom portions 14 are rough surfaces, that is, the surface covering and contacting the encapsulant 34 is rough surface, so that The encapsulant 34 can be further dissolved into the fine gap of the rough surface to improve the adhesion strength of the encapsulant 34.

More importantly, since the heat sink 10 has a total area, the plurality of support bottoms 14 only occupy the four corners of the heat sink 10, and the other portions are reserved for the center portion 12, and therefore, the center portion 12 in addition to the basic square middle area, added four more The area of the protruding side strips can be installed correspondingly to the volume of the wafer, and the plurality of supporting bottoms 14 can also accommodate the wafer, which can minimize the volume and thus does not interfere with other parts, so the heat sink 10 can be The use of larger wafers can also be used to achieve a streamlined space.

In summary, the present invention utilizes the edge of the central portion 12 to be recessed to form a plurality of support bottom portions 14, such that the proportion of the support bottom portion 14 relative to the heat sink 10 is minimized, and the center portion 12 can produce the maximum range. The heat dissipation area is used to effectively meet the demand for thin and light wafers, thereby achieving the goal of streamlining space.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

12‧‧‧ Central Department

14‧‧‧Support bottom

16‧‧‧Connecting Department

18‧‧‧End

20‧‧‧ first datum

26‧‧‧ openings

Claims (6)

A heat sink comprising: a central portion having a first reference surface and a second reference surface opposite to the first reference surface, the first reference surface and the second reference surface defining a thickness D; A plurality of support bottoms are located at four corners of the central portion and are concave with respect to the first reference surface, each support bottom having a support bottom surface, and a height H is defined between the support bottom surface and the first reference surface The height H is greater than the thickness D, and the heat sink disposed at the bottom of the four supports may increase the area of the area where the wafer is pasted; a plurality of connecting portions respectively connecting the center portion and the supporting bottom portion corresponding to each other; and a plurality of ends And each end portion is lifted by a corresponding support bottom toward the first reference surface. The heat sink of claim 1, wherein the central portion has at least one opening. The heat sink according to claim 1, wherein the second reference surface of the central portion and the support bottom surface of the plurality of support bottoms are rough surfaces. A package structure comprising: a substrate; a flip chip; the flip chip is disposed on the substrate; a heat sink comprising a central portion, a plurality of support bottoms, a plurality of connecting portions, and a plurality of end portions, wherein The central portion has a first reference surface and a second reference surface opposite to the first reference surface, the first A thickness D is defined between a reference surface and the second reference surface, the plurality of support bottoms are at four corners of the central portion and are concave with respect to the first reference surface, and each support bottom has a support a bottom surface, a height H is defined between the bottom surface of the support and the first reference surface, and the height H is greater than the thickness D. The heat sink disposed on the bottom of the support base can add more area area of the adhesive wafer, and the plurality of connecting portions Connecting the central portion and the supporting bottom portions respectively corresponding to each other, each end portion being lifted by a corresponding supporting bottom toward the first reference surface; and an encapsulant colliding the flip chip, and at least Part of the substrate and at least a portion of the heat sink. The package structure of claim 4, wherein the central portion has at least one opening. The package structure according to claim 4, wherein the second reference surface of the central portion and the support bottom surface of the plurality of support bottoms are rough surfaces.