TWI776768B - Heat dissipating sheet and chip on film package structure - Google Patents

Abstract

A heat dissipating sheet and a chip on film package structure are provided. The heat dissipating sheet includes an insulating protective layer, a heat dissipating metal layer, a first adhesive layer and a second adhesive layer. The heat dissipating metal layer has a first side and a second side opposite to each other. The second side has a plurality of indentations, and the plurality of indentations is located on at least an edge of the second side. The first adhesive layer is disposed between the insulating protective layer and the first side of the heat dissipating metal layer. The heat dissipating metal layer is attached to the insulating protective layer by the first adhesive layer. The second adhesive layer is disposed on the second side of the heat dissipating metal layer.

Description

Thermal patch and thin film flip chip package structure

The present invention relates to a patch and a package structure, and particularly to a heat dissipation patch and a film-on-chip packaging structure using the heat dissipation patch.

In the current chip on film (COF) package, in order to improve the heat dissipation effect, a flexible thin heat dissipation patch is attached to the surface of the package structure, especially where the heat source (such as a chip) is located. Generally speaking, when the chip-on-film packaging structure with the heat dissipation chip attached is judged to be a defective product, in order to avoid the adhesive of the heat dissipation chip remaining on the tool during the punching process of the defective product, the tool loss will be caused , Generally, the heat dissipation patch needs to be torn off first, and then punched. However, since the current heat dissipation patch is a flexible thin layer structure and its attaching surface is a flat surface, the heat dissipation patch is usually adhered to the film-on-chip package structure, which is difficult and time-consuming to remove.

The present invention provides a heat-dissipating patch, which can improve the convenience of tearing off by a user, and can effectively shorten the operation time.

The present invention provides a film-on-chip packaging structure, including the above-mentioned heat dissipation patch, which can improve the convenience of a user when removing the heat dissipation patch, thereby effectively shortening the operation time.

The heat dissipation patch of the present invention includes an insulating protective layer, a heat dissipation metal layer, a first adhesive layer and a second adhesive layer. The heat dissipation metal layer has a first side surface and a second side surface opposite to each other. The second side surface has a plurality of concave grooves, and the concave grooves are located at at least one edge of the second side surface. The first adhesive layer is disposed between the insulating protection layer and the first side surface of the heat dissipation metal layer. The heat dissipation metal layer is attached to the insulating protection layer through the first adhesive layer. The second adhesive layer is disposed on the second side surface of the heat dissipation metal layer.

In an embodiment of the present invention, the depth of the above-mentioned concave grooves is less than 1/2 of the thickness of the heat dissipation metal layer.

In an embodiment of the present invention, the area occupied by the concave grooves is less than 1/3 of the total area of the heat dissipation metal layer.

In an embodiment of the present invention, the above-mentioned second adhesive layer exposes indentations.

In an embodiment of the present invention, the above-mentioned concave grooves are located at two edges connected to the second side surface of the heat dissipation metal layer.

The film-on-chip package structure of the present invention includes a flexible circuit carrier board, a chip and a heat dissipation patch. The flexible circuit carrier has a first surface and a second surface opposite to each other and a chip setting area defined on the first surface. The chip is arranged in the chip setting area and is electrically connected with the flexible circuit carrier board. The heat dissipation patch is disposed on the first surface or the second surface of the flexible circuit carrier and corresponds to the chip setting area. The heat dissipation patch includes an insulating protection layer, a heat dissipation metal layer, a first adhesive layer and a second adhesive layer. The heat dissipation metal layer has a first side surface and a second side surface opposite to each other. The second side surface has a plurality of concave grooves, and the concave grooves are located at at least one edge of the second side surface. The first adhesive layer is disposed between the insulating protection layer and the first side surface of the heat dissipation metal layer. The heat dissipation metal layer is attached to the insulating protection layer through the first adhesive layer. The second adhesive layer is disposed on the second side surface of the heat dissipation metal layer. The heat dissipation patch is attached to the first surface of the flexible circuit carrier and the chip or the second surface of the flexible circuit carrier through the second adhesive layer.

In an embodiment of the present invention, the depth of the above-mentioned concave grooves is less than 1/2 of the thickness of the heat dissipation metal layer.

In an embodiment of the present invention, the area occupied by the concave grooves is less than 1/3 of the total area of the heat dissipation metal layer.

In an embodiment of the present invention, the above-mentioned second adhesive layer exposes indentations.

In an embodiment of the present invention, the above-mentioned concave grooves are located at two edges connected to the second side surface of the heat dissipation metal layer.

Based on the above, since the indentations are located at at least one edge of the second side surface of the heat-dissipating metal layer, the heat-dissipating patch of the present invention forms a rough surface with a height difference at the edge, thereby, the film of the defective product can be punched In the step of peeling off the heat dissipation patch before the flip chip package structure, the convenience for the user to peel off can be improved, and the operation time can be effectively shortened. In addition, the present invention adopts the film-on-chip packaging structure of the heat dissipation patch, which can effectively improve the production efficiency.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are given and described in detail with the accompanying drawings as follows.

The present invention is more fully described with reference to the drawings of this embodiment. However, the present invention may be embodied in various forms and should not be limited to the embodiments described herein. The thickness, size or size of layers or regions in the drawings may be exaggerated for clarity.

It should be noted that the chip-on-film packaging structure in the following figures is operated in a tape-and-reel mode, although the heat sink in the figures below is only schematically shown applied to the tape and tape forming the chip-on-film packaging structure. However, the present invention is not limited to this, and the heat dissipation patches of the following figures can be applied to a plurality of device areas on the tape at the same time.

FIG. 1 is a schematic perspective view of a heat dissipation patch according to an embodiment of the present invention. FIG. 2A is a schematic cross-sectional view of an embodiment of a heat dissipation patch taken along the line A-A' of FIG. 1 . Fig. 2B is a schematic cross-sectional view of another embodiment of the heat dissipation patch taken along the line A-A' of Fig. 1 . For the sake of clarity, FIG. 1 omits to illustrate some components (eg, the first adhesive layer 130 and the second adhesive layer 140 ), and only schematically illustrates the insulating protection layer 110 , the heat-dissipating metal layer 120 and the plurality of indentations 124 .

Please refer to FIG. 1 and FIG. 2A simultaneously. In this embodiment, the heat dissipation patch 100 includes an insulating protection layer 110 , a heat dissipation metal layer 120 , a first adhesive layer 130 and a second adhesive layer 140 . The material of the insulating protection layer 110 is, for example, a flexible material such as polyimide (PI), which is used to protect the heat dissipation metal layer 120 to prevent the heat dissipation metal layer 120 from being scratched and damaged. The heat-dissipating metal layer 120 has a first side 121 and a second side 122 opposite to each other, wherein the material of the heat-dissipating metal layer 120 may include metal foil or graphite thin film, and the metal foil is, for example, aluminum foil or copper foil, but the present invention does not use this limited. The first adhesive layer 130 is disposed between the insulating protection layer 110 and the first side surface 121 of the heat dissipation metal layer 120 , and the heat dissipation metal layer 120 is attached to the insulating protection layer 110 through the first adhesive layer 130 . The second adhesive layer 140 is disposed on the second side surface 122 of the heat-dissipating metal layer 120 , which facilitates the subsequent attachment of the heat-dissipating metal layer 120 to the heating element (eg, a chip-on-film package).

In particular, in this embodiment, the second side surface 122 of the heat dissipation metal layer 120 has a plurality of concave grooves 124 , and the concave grooves 124 are located at at least one edge 123 of the second side surface 122 . For example, in this embodiment, the concave grooves 124 may be located at the two edges 123 a and 123 b connected to the second side surface 122 of the heat dissipation metal layer 120 , but the invention is not limited thereto. The indentations 124 may be, for example, three-dimensional embossing, but not limited thereto, as long as a pattern with a non-flat surface can be formed, it falls within the scope of the present invention.

It should be understood that the present embodiment merely illustrates the concave grooves 124 located at the two edges 123 a and 123 b connected to the second side surface 122 of the heat dissipation metal layer 120 , but is not intended to limit the present invention. In other not-shown embodiments, the concave grooves 124 may be disposed at any one or more edges of the second side surface 122 of the heat dissipation metal layer 120 according to actual requirements.

In one embodiment, the heat dissipation metal layer 120 has a thickness T1, and the grooves 124 on the second side surface 122 of the heat dissipation metal layer 120 have a depth T2. Preferably, the depth T2 of these concave grooves 124 is, for example, less than 1/2 of the thickness T1 of the heat dissipation metal layer 120 , but the invention is not limited to this. In other embodiments, the depth T2 of the grooves 124 can also be adjusted according to actual needs. Here, the thickness T1 of the heat dissipation metal layer 120 is, for example, 25 microns or 50 microns, but not limited thereto.

In one embodiment, the area occupied by the concave grooves 124 on the second side surface 122 of the heat dissipation metal layer 120 is, for example, less than 1/3 of the total area of the heat dissipation metal layer 120 , but the invention is not limited thereto. In other embodiments, the size of the area occupied by the concave grooves 124 can be adjusted according to actual needs, so as to facilitate the user to remove the heat dissipation patch 100 .

In addition, as shown in FIG. 1 and FIG. 2A , in this embodiment, the second adhesive layer 140 disposed on the second side surface 122 of the heat dissipation metal layer 120 can cover most of the second side surface 122 of the heat dissipation metal layer 120 but The dimples 124 are exposed, so that most of the sidewalls of the second adhesive layer 140 are flush with the edge of the heat dissipation metal layer 120 , but one of the sidewalls 140s is located outside the regions of the dimples 124 . That is to say, the concave grooves 124 are not covered by the second adhesive layer 140, so that the rough surfaces at the concave grooves 124 are exposed, but the invention is not limited thereto. In other embodiments, the dimples 124 may not be exposed by the second adhesive layer 140 . For example, referring to FIG. 2B , the sidewall of the second adhesive layer 140 is completely aligned with the edge of the heat dissipation metal layer 120 , that is, the second adhesive layer 140 completely covers the second side surface 122 of the heat dissipation metal layer 120 . In addition, the second adhesive layer 140 can be conformally disposed with the heat dissipation metal layer 120 at the concave grooves 124 , so that the surface 142 of the second adhesive layer 140 also has a non-flat surface similar to the concave grooves 124 .

In one embodiment, the size of the first adhesive layer 130 may be approximately equal to the size of the heat-dissipating metal layer 120 and located within the range of the heat-dissipating metal layer 120, so that the maximum bonding area between the heat-dissipating metal layer 120 and the insulating protection layer 110 is achieved, It can improve the bonding effect between the two. The thickness T3 of the first adhesive layer 130 is smaller than the thickness T4 of the second adhesive layer 140, wherein the thickness T3 of the first adhesive layer 130 is, for example, 20 microns, and the thickness T4 of the second adhesive layer 140 is, for example, 60 microns, but not the same limited.

In one embodiment, the size of the insulating protection layer 110 is larger than that of the heat dissipation metal layer 120 , and the insulating protection layer 110 completely covers the heat dissipation metal layer 120 to protect the heat dissipation metal layer 120 , but the invention is not limited thereto.

3 is a schematic perspective view of a heat dissipation patch according to another embodiment of the present invention. FIG. 4A is a schematic cross-sectional view of an embodiment of a heat dissipation patch taken along the line B-B' of FIG. 3 . FIG. 4B is a schematic cross-sectional view of another embodiment of the heat dissipation patch taken along the line B-B' of FIG. 3 . The perspective schematic diagram of FIG. 3 is substantially similar to the perspective schematic diagram of FIG. 1 , so the same components described in the two embodiments may refer to the foregoing content, and the same configurations in the two embodiments will not be repeated here.

Referring to FIG. 3 and FIG. 4A at the same time, in the heat dissipation patch 100 ′ of the present embodiment, the second side surface 122 of the heat dissipation metal layer 120 has a plurality of concave grooves 124 ′, and the concave grooves 124 ′ are located on the second side surface 122 at one of the edges 123a. For example, as shown in FIG. 3 , the concave grooves 124 ′ may be located at the center of a short side of the second side surface 122 of the heat dissipation metal layer 120 , but the present invention is not limited to this, and other implementations not shown For example, these concave grooves 124 ′ can be arranged anywhere on any edge according to actual requirements. In addition, in other not-shown embodiments, the concave grooves 124' can also be disposed at any positions of the plurality of edges on the second side surface 122 of the heat dissipation metal layer 120 according to actual requirements.

Please refer to FIG. 4A again. Similar to the schematic cross-sectional view of FIG. 2A , in this embodiment, the second adhesive layer 140 disposed on the second side surface 122 of the heat dissipation metal layer 120 can also cover the second side surface 122 of the heat dissipation metal layer 120 most of the indentations 124' are exposed. That is, these concave grooves 124' are not covered by the second adhesive layer 140. 3 and FIG. 4A , since these concave grooves 124 ′ are located at one edge 123 a of the second side surface 122 in this embodiment and the second adhesive layer 140 exposes these concave grooves 124 ′, they are disposed on the heat dissipation metal The local sidewalls 140s' of the second adhesive layer 140 on the second side surface 122 of the layer 120 may surround the grooves 124' to expose the rough surface of the grooves 124', but the invention is not limited thereto . In other embodiments, the second adhesive layer 140 may not expose these concave grooves 124'. For example, referring to FIG. 4B , the sidewall of the second adhesive layer 140 is completely aligned with the edge of the heat dissipation metal layer 120 , that is, the second adhesive layer 140 completely covers the second side 122 of the heat dissipation metal layer 120 . In addition, the second adhesive layer 140 may be conformally disposed with the heat dissipation metal layer 120 at the concave grooves 124', so that the surface 142' of the second adhesive layer 140 also has a non-flat surface similar to the concave grooves 124'.

Since the heat dissipation patches 100 , 100 ′ respectively have these indentations 124 , 124 ′ located at at least one edge 123 on the second side surface 122 of the heat dissipation metal layer 120 , the heat dissipation patches 100 , 100 ′ are formed at the edges with The rough surface with different heights is beneficial to the convenience of the user when tearing off, which can effectively shorten the operation time.

It must be noted here that the following embodiments use the element numbers and parts of the above-mentioned embodiments, wherein the same or similar numbers are used to represent the same or similar elements, and the description of the same technical content is omitted, and the description of the omitted part is omitted. Reference may be made to the foregoing embodiments, and detailed descriptions in the following embodiments will not be repeated.

FIG. 5 is a schematic top view of a chip on film package structure according to the embodiment shown in FIG. 1 according to the present invention. FIG. 6 is a schematic cross-sectional view of the chip on film package structure of FIG. 5 . For the sake of clarity, some components are omitted in FIG. 5 , and the omitted parts can be understood with reference to the schematic cross-sectional view in FIG. 6 .

Please refer to FIG. 1 , FIG. 5 and FIG. 6 at the same time, the chip on film package structure 10 of the present embodiment includes, for example, the heat dissipation patch 100 , the flexible circuit carrier 200 and the chip 300 as described above. The flexible circuit carrier 200 has a first surface 201 and a second surface 202 opposite to each other, and a chip placement area 201 a defined on the first surface 201 . The chip 300 may be disposed in the chip setting area 201 a in a flip-chip manner and electrically connected to the flexible circuit carrier board 200 . The heat dissipation patch 100 is disposed on the first surface 201 of the flexible circuit carrier 200 and corresponds to the chip setting area 201 a, wherein the heat dissipation patch 100 can be attached to the first surface of the flexible circuit carrier 200 through the second adhesive layer 140 . A surface 201 covers the wafer 300 .

It should be noted that, although the heat dissipation patch 100 is only disposed on the first surface 201 in this embodiment, the present invention does not limit the surface to which the heat dissipation patch 100 is attached, nor does it limit the attached surface and the number thereof . As long as the heat dissipation patch 100 is disposed on at least one of the first surface 201 and the second surface 202 , it belongs to the protection scope of the present invention. For example, in other embodiments, the heat dissipation patch 100 may also be disposed only on the second surface 202 or on both the first surface 201 and the second surface 202 . That is, in other embodiments, the heat dissipation patch 100 can also be disposed on the second surface 202 of the flexible circuit carrier 200 and correspond to the chip setting area 201 a, and the heat dissipation patch 100 can pass through the second adhesive layer 140 attached to the second surface 202 of the flexible circuit carrier 200; or, there may be two heat dissipation patches 100, which are respectively disposed on the first surface 201 and the second surface 202 of the flexible circuit carrier 200 , the above all belong to the scope of protection of the present invention.

Here, the flexible circuit carrier 200 may include a flexible substrate 210 , a plurality of pins 220 and a solder resist layer 230 . The material of the flexible substrate 210 is, for example, polyethylene terephthalate (PET), polyimide (PI), polyethersulfone (PES), carbonate (PC) or Other suitable flexible materials. The flexible substrate 210 has an upper surface 211 and a lower surface 212 opposite to each other, and the pins 220 are disposed on the upper surface 211 of the flexible substrate 210 . The solder mask layer 230 is disposed on the upper surface 211 of the flexible substrate 210 and is located outside the chip disposing area 201a and partially covers the plurality of pins 220 to prevent the pins 220 from being damaged or bridged and short-circuited by foreign objects. The exposed portions of the plurality of pins 220 by the solder mask layer 230 can be used for electrical connection with the chip 300 or external components. The material of the solder resist layer 230 is, for example, green paint, which is not limited herein.

In one embodiment, the chip on film package structure 10 further includes an adhesive filler layer 310 , wherein the adhesive filler layer 310 can be filled between the flexible substrate 210 and the chip 300 to prevent the intrusion of moisture or foreign matter to cause electrical contacts damage or electrical abnormalities. The material of the filling layer 310 is, for example, underfill, but not limited thereto.

Since the chip on film package structure 10 of the present embodiment includes the heat dissipation patch 100 , and the heat dissipation patch 100 has these indentations 124 on at least one edge 123 on the second side surface 122 of the heat dissipation metal layer 120 , the heat dissipation patch 100 can The sheet 100 can be easily torn off, thereby improving the production efficiency of the chip on film package structure 10 . It should be understood that although only an embodiment of the chip on film package structure 10 including the heat dissipation patch 100 is shown, it is not intended to limit the present invention. In other not-shown embodiments, the chip on film package structure may also include the aforementioned heat dissipation patch 100'.

To sum up, since the concave grooves are located at at least one edge of the second side surface of the heat dissipation metal layer, the heat dissipation patch of the present invention forms a rough surface with a height difference at the edge, thereby preventing the punching of defective products. In the step of peeling off the heat dissipation patch before the thin film-on-chip package structure, the convenience of the user's peeling can be improved, and the operation time can be effectively shortened. In addition, the present invention adopts the film-on-chip packaging structure of the heat dissipation patch, which can effectively improve the production efficiency.

Although the present invention has been disclosed above by the embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, The protection scope of the present invention shall be determined by the scope of the appended patent application.

10: Thin film flip chip packaging structure 100, 100': heat dissipation patch 110: Insulation protective layer 120: heat dissipation metal layer 121: The first side 122: Second side 123, 123a, 123b: Edge 124, 124': Indentation 130: The first adhesive layer 140: The second adhesive layer 140s, 140s’: sidewall 142, 142': surface 211: Upper surface 212: Lower Surface 200: Flexible circuit carrier board 201: First Surface 201a: Wafer setting area 202: Second Surface 210: Flexible Substrate 220: pin 230: Solder mask 300: Wafer 310: Filler layer T1, T3, T4: Thickness T2: Depth

FIG. 1 is a schematic perspective view of a heat dissipation patch according to an embodiment of the present invention. FIG. 2A is a schematic cross-sectional view of an embodiment of a heat dissipation patch taken along the line A-A' of FIG. 1 . Fig. 2B is a schematic cross-sectional view of another embodiment of the heat dissipation patch taken along the line A-A' of Fig. 1 . 3 is a schematic perspective view of a heat dissipation patch according to another embodiment of the present invention. FIG. 4A is a schematic cross-sectional view of an embodiment of a heat dissipation patch taken along the line B-B' of FIG. 3 . FIG. 4B is a schematic cross-sectional view of another embodiment of the heat dissipation patch taken along the line B-B' of FIG. 3 . FIG. 5 is a schematic top view of a chip on film package structure according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view of the chip on film package structure of FIG. 5 .

100: heat dissipation patch

110: Insulation protective layer

120: heat dissipation metal layer

123, 123a, 123b: Edge

124: Indentation

140s: Sidewalls

Claims (10)

A heat dissipation patch, comprising: an insulating protective layer; a heat-dissipating metal layer, which has a first side surface and a second side surface opposite to each other, the second side surface has a plurality of concave grooves, and the concave grooves are located at at least one edge of the second side surface; a first adhesive layer disposed between the insulating protective layer and the first side surface of the heat-dissipating metal layer, the heat-dissipating metal layer is attached to the insulating protective layer through the first adhesive layer; and A second adhesive layer is disposed on the second side surface of the heat dissipation metal layer. The heat dissipation patch according to claim 1, wherein the depth of the recesses is less than 1/2 of the thickness of the heat dissipation metal layer. The heat dissipation patch according to claim 1, wherein the area occupied by the concave grooves is less than 1/3 of the total area of the heat dissipation metal layer. The heat dissipation patch according to claim 1, wherein the second adhesive layer exposes the indentations. The heat dissipation patch of claim 1, wherein the concave grooves are located at two edges connected to the second side surface of the heat dissipation metal layer. A film-on-chip packaging structure, comprising: a flexible circuit carrier having a first surface and a second surface opposite to each other and a chip setting area defined on the first surface; a chip, disposed in the chip setting area and electrically connected with the flexible circuit carrier; and A heat dissipation patch, disposed on the first surface or the second surface of the flexible circuit carrier and corresponding to the chip setting area, the heat dissipation patch includes: an insulating protective layer; a heat-dissipating metal layer, which has a first side surface and a second side surface opposite to each other, the second side surface has a plurality of concave grooves, and the concave grooves are located at at least one edge of the second side surface; a first adhesive layer disposed between the insulating protective layer and the first side surface of the heat-dissipating metal layer, the heat-dissipating metal layer is attached to the insulating protective layer through the first adhesive layer; and a second adhesive layer disposed on the second side of the heat dissipation metal layer, wherein the heat dissipation patch is attached to the first surface of the flexible circuit carrier and the chip or through the second adhesive layer on the second surface of the flexible circuit carrier. The chip-on-film package structure of claim 6, wherein the depth of the recesses is less than 1/2 of the thickness of the heat dissipation metal layer. The chip on film package structure of claim 6, wherein the area occupied by the concave grooves is less than 1/3 of the total area of the heat dissipation metal layer. The chip-on-film packaging structure of claim 6, wherein the second adhesive layer exposes the concavities. The chip on film package structure of claim 6, wherein the concave grooves are located at two edges connected to the second side surface of the heat dissipation metal layer.

Images