Heat dissipation auxiliary fin and chip-on-film packaging structure with same

Abstract

The utility model relates to a heat dissipation auxiliary fin and a thin film flip chip packaging structure with the heat dissipation auxiliary fin, the heat dissipation auxiliary fin comprises an insulation protection layer, a first adhesive layer, a heat dissipation film material layer and a second adhesive layer which are sequentially arranged in a stacked mode from top to bottom, and the heat dissipation auxiliary fin is provided with a chip matching area corresponding to the position of a chip in the thin film flip chip packaging structure. The heat dissipation film material layer is provided with a first heat dissipation part corresponding to the chip matching area and a punching preset part which is arranged on the periphery of the first heat dissipation part, and the shearing strength of the punching preset part is smaller than that of the first heat dissipation part. Based on the specific structure of the heat dissipation auxiliary fin provided by the utility model, when the heat dissipation auxiliary fin is applied to the scene of a thin film flip chip packaging structure, the existing process of thin film flip chip packaging does not need to be changed, and when the thin film flip chip packaging structure needs to be punched, the resistance of a punching tool bit can be reduced through the arrangement of the punching preset part in the heat dissipation auxiliary fin, so that the heat dissipation efficiency is improved. And the punching success rate can be improved.

Description

Technical Field

[0001] The utility model relates to the field of chip-on-film packaging, in particular to a heat dissipation auxiliary sheet and a chip-on-film packaging structure having the same. Background Art

[0002] As the core component of display screens, the chip-on-film (COF) packaging structure has significantly increased the number of channels on its internal integrated circuit chips and flexible circuit boards with the rise of high-definition and high-refresh rate display screen technologies and the trend of chip miniaturization and functional integration. This has led to an increase in the power consumption of the integrated circuit during operation. In order to maintain a stable operating temperature, it is necessary to use heat dissipation auxiliary materials on the surface of the chip-on-film packaging structure to dissipate heat.

[0003] In the production process, whether it is the film flip chip packaging structure itself or the chip and flexible circuit materials therein, there may be defects, so punching is required. However, when the heat dissipation auxiliary material is applied to the film flip chip packaging structure, its punching success rate will be seriously affected by the thickness of the structure, especially when the heat dissipation auxiliary material is thicker, the success rate of tool punching will be reduced. In addition, the metal / graphite layer in the heat dissipation auxiliary material may produce debris during the punching process. Once these debris adhere to the good product, they may cause short circuit or open circuit problems, especially in the production process of the terminal product, these debris may also cause more serious debris problems. At the same time, the adhesive layer in the heat dissipation auxiliary material will leave adhesive residue on the tool during the punching process, which not only reduces the efficiency of the tool and shortens its service life, but also the residual adhesive on the film flip chip packaging structure after punching may overflow during winding and pressurization, thereby contaminating the good product.

[0004] In view of the above, the industry urgently needs an improved technical solution. Utility Model Content

[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. To achieve the above-mentioned purpose of the utility model, the utility model provides a heat dissipation auxiliary sheet, and its specific design method is as follows.

[0006] A heat dissipation auxiliary sheet is used to assist the heat dissipation of a thin film chip-on-chip packaging structure. The heat dissipation auxiliary sheet includes an insulating protection layer, a first adhesive layer, a heat dissipation film material layer and a second adhesive layer stacked in sequence from top to bottom. The heat dissipation auxiliary sheet has a chip matching area corresponding to the position of the chip in the thin film chip-on-chip packaging structure. The heat dissipation film material layer has a first heat dissipation portion corresponding to the chip matching area and a punching preset portion arranged around the first heat dissipation portion and having a shear strength less than the shear strength of the first heat dissipation portion.

[0007] Furthermore, the heat dissipation film material layer also has a second heat dissipation portion which is arranged around the punching pre-set portion and has a shear strength greater than the shear strength of the punching pre-set portion.

[0008] Furthermore, the punching pre-set portion is arranged in a closed shape around the first heat dissipation portion.

[0009] Furthermore, the thickness of the punched pre-set portion is smaller than the thickness of the first heat dissipation portion.

[0010] Furthermore, the punching preset portion is preset with a plurality of through holes or blind holes distributed at intervals.

[0011] Furthermore, the punching preset portion is preset with a cutting groove.

[0012] Furthermore, the heat dissipation film material layer is a metal layer and / or a graphite layer.

[0013] Further, at least one of the first adhesive layer and the second adhesive layer is configured as an adhesive-free area at a position corresponding to the punching preset portion.

[0014] Furthermore, the glue-free area extends outward to the edge of the heat dissipation auxiliary sheet.

[0015] The utility model also provides a film-on-chip packaging structure, which includes a chip and a flexible circuit board, wherein the flexible circuit board has a chip bonding area for electrically connecting the chip and a preset bad punching area defined around the chip bonding area; the film-on-chip packaging structure also has a heat dissipation auxiliary sheet as described above, which is arranged on at least one surface side of the flexible circuit board, and the punching preset portion of the heat dissipation auxiliary sheet corresponds to the position of the preset bad punching area.

[0016] The beneficial effects of the present invention are as follows: based on the specific structure of the heat dissipation auxiliary sheet provided by the present invention, when it is applied to a thin film flip chip packaging structure, there is no need to change the existing process of the thin film flip chip packaging, and when the thin film flip chip packaging structure needs to be punched, the setting of the punching pre-set portion in the heat dissipation auxiliary sheet can reduce the resistance of the punching head and improve the punching success rate; in addition, keeping the punching smooth can also reduce the generation of debris during the punching process to a certain extent, thereby improving the yield of the terminal product. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0018] Figure 1 The figure is a plan view of an implementation structure of the heat dissipation auxiliary sheet of the utility model;

[0019] Figure 2 Shown Figure 1 Schematic diagram of the cross section at the AA' position;

[0020] Figure 3 Shown Figure 2 The enlarged schematic diagram of part a in the middle;

[0021] Figure 4 The figure shows an implementation structure of the thin film chip packaging structure of the utility model;

[0022] Figure 5 Another embodiment of the thin film flip chip packaging structure of the utility model is shown.

[0023] Figure 6 Shown Figure 2 The schematic diagram of the second implementation structure of the middle a part;

[0024] Figure 7 Shown Figure 2 Schematic diagram of the third implementation structure of the middle a part

[0025] Figure 8 Shown Figure 2 The fourth implementation structure schematic diagram of the middle a part;

[0026] Fig. 9 Shown Figure 2 The fifth implementation structure schematic diagram of part a in the middle.

[0027] In the figure, 100-heat dissipation auxiliary sheet, 11-insulating protection layer, 12-first glue layer, 120-first glue-free area, 13-heat dissipation film material layer, 131-first heat dissipation part, 132-punching pre-set part, 133-second heat dissipation part, 14-second glue layer, 140-second glue-free area, 200-chip, 300-flexible circuit board, 31-flexible circuit substrate, 32-pin, 33-solder mask, 400-punching head. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] refer to Figure 1 , Figure 2 , Figure 3As shown in the figure, a specific implementation structure of the heat dissipation auxiliary sheet 100 of the utility model is shown. As shown in the figure, the heat dissipation auxiliary sheet 100 includes an insulating protective layer 11, a first adhesive layer 12, a heat dissipation film material layer 13 and a second adhesive layer 14 stacked in sequence from top to bottom. Figure 4 As shown, the heat dissipation auxiliary sheet 100 has a chip matching area (not marked in the figure) corresponding to the position of the chip 200 in the film flip chip packaging structure, and the heat dissipation film material layer 13 has a first heat dissipation portion 131 corresponding to the chip matching area and a punching pre-set portion 132 arranged around the first heat dissipation portion 131 and having a shear strength less than the shear strength of the first heat dissipation portion 131.

[0030] In order to better understand the content of the present invention, the present invention also provides an implementation method of a chip-on-film packaging structure, a specific implementation example of which is as follows: Figure 4 As shown, the film-on-chip packaging structure involved in this embodiment includes a chip 200 and a flexible circuit board 300, wherein the flexible circuit board 300 has a chip bonding area (i.e., an area corresponding to the position of the chip 200, not marked in the figure) for electrical connection of the chip 200 and a preset bad punching area (not marked in the figure) defined around the chip bonding area. The film-on-chip packaging structure also has a heat dissipation auxiliary sheet 100 disposed on at least one surface side of the flexible circuit board 300, wherein the punching preset portion 132 of the heat dissipation auxiliary sheet 100 corresponds to the position of the preset bad punching area.

[0031] It can be understood that the heat dissipation auxiliary sheet 100 involved in the utility model is adhered to the surface side of the flexible circuit board 300 through the second adhesive layer 14. During the specific implementation process, a roller (not shown) or other mechanism can be used for rolling to make the heat dissipation auxiliary sheet 100 adhere to the flexible circuit board 300; the heat dissipation auxiliary sheet 100 is used to assist the heat dissipation of the thin film flip chip packaging structure, thereby optimizing the function of the thin film flip chip packaging structure.

[0032] Further references Figure 4 As shown, the flexible circuit board 300 generally includes a flexible circuit substrate 31, pins 32 arranged on the flexible circuit substrate 31, and a solder mask 33 formed around the chip bonding area. The chip 200 is electrically connected to the pins 32 through bumps (not marked in the figure), and the solder mask 33 partially covers the pins 32. In the specific implementation process, the thin film chip package structure 10 may also include a filling layer (not marked in the figure), wherein the filling layer is arranged between the chip 200 and the flexible circuit board 300, and covers the bumps and at least part of the pins 32 to prevent moisture and contaminants from affecting the electrical connection between the bumps and the pins 32.

[0033] Based on the specific structure of the heat dissipation auxiliary sheet 100 provided by the utility model, when it is applied to the film flip chip packaging structure, there is no need to change the existing film flip chip packaging process. Figure 4 As shown in , the setting of the punching pre-set portion 132 in the heat dissipation auxiliary sheet 100 can reduce the resistance of the punching head 400 and improve the punching success rate; in addition, the smooth punching can also reduce the generation of debris during the punching process to a certain extent, thereby improving the yield of the terminal product.

[0034] In addition, reference Figure 4 As shown, in this embodiment, the thin film chip packaging structure is only provided with a heat dissipation auxiliary sheet 100 on one surface side of the flexible circuit board 300 on which the chip is provided; it can be understood that in other embodiments of the utility model, reference Figure 5 As shown, the chip-on-film packaging structure can also be provided with a heat dissipation auxiliary sheet 100 on both surfaces of the flexible circuit board 300, thereby further optimizing the heat dissipation effect of the chip-on-film packaging structure; in addition, in some embodiments not shown in the figure, the chip-on-film packaging structure can also be provided with a heat dissipation auxiliary sheet 100 on a surface side of the flexible circuit board 300 where the chip is not provided.

[0035] Combination Figure 1 , Figure 2 , Figure 3 As shown, in some embodiments of the present invention, the heat dissipation film layer 13 further has a second heat dissipation portion 133 disposed around the punching pre-set portion 132 and having a shear strength greater than the shear strength of the punching pre-set portion 132. The provision of the second heat dissipation portion 133 is equivalent to increasing the area of ​​the heat dissipation film layer 13, thereby ensuring that the heat dissipation film layer 13 has a better heat dissipation effect.

[0036] As a further preferred embodiment, in some embodiments of the present invention, the punching pre-set portion 132 is arranged in a closed shape around the first heat dissipation portion 131. Based on this arrangement, the resistance encountered by the punching head 400 during the punching process can be reduced to the greatest extent. As shown in Reference 1, in this embodiment, the punching pre-set portion 132 is in a closed rectangular frame shape.

[0037] In order to make the shear strength of the punching pre-set portion 132 smaller than the shear strength of the first heat dissipation portion 131 , the utility model provides the following specific implementation methods.

[0038] refer to Figure 3 As shown in , in some embodiments of the present invention, the thickness of the punching pre-set portion 132 is set to be smaller than the thickness of the first heat dissipation portion 131 , so that the shear strength of the punching pre-set portion 132 is smaller than the shear strength of the first heat dissipation portion 131 .

[0039] refer to Figure 6As shown in , in other embodiments of the present invention, a plurality of through holes or blind holes distributed at intervals are preset in the punching pre-set portion 132 , so that the shear strength of the punching pre-set portion 132 is smaller than the shear strength of the first heat dissipation portion 131 .

[0040] refer to Figure 7 As shown in , in some other embodiments of the present invention, a cutting groove is preset in the pre-punching portion 132 , so that the shear strength of the pre-punching portion 132 is smaller than the shear strength of the first heat dissipation portion 131 .

[0041] It can be understood that the various specific implementations listed above are mainly for a better understanding of the present invention rather than limiting it. In other embodiments of the present invention, other technical means can also be used to achieve the purpose of making the shear strength of the punching preset portion 132 less than the shear strength of the first heat dissipation portion 131.

[0042] In the present invention, in order to achieve a better heat dissipation effect, the heat dissipation film material layer 13 is preferably a metal layer and a graphite layer or a combination of the two. The metal layer involved can be an aluminum film, a copper film, etc.

[0043] In addition, the material of the insulating protection layer 110 in the present invention may be polyimide (PI).

[0044] As a further preferred embodiment of the present invention, at least one of the first adhesive layer 12 and the second adhesive layer 14 is provided as an adhesive-free area at a position corresponding to the punching pre-set portion 132. Figure 8 As shown, in this specific embodiment, the first adhesive layer 12 and the second adhesive layer 14 are respectively provided with a first adhesive-free area 120 and a second adhesive-free area 140 at positions corresponding to the punching pre-set portion 132. It can be understood that in other embodiments of the utility model, the adhesive-free area can also be provided only on one of the first adhesive layer 12 and the second adhesive layer 14. It is relatively easy to understand that the adhesive-free area refers to the area where there is no adhesive.

[0045] In this embodiment, due to the setting of the glue-free area, when the punching head 400 punches the heat dissipation auxiliary sheet 100, the punching head 400 can perform the punching action in the glue-free area, thereby avoiding the adhesive residue on the punching head 400 after punching. This not only improves the efficiency of the tool and extends its service life, but also eliminates the problem of adhesive contaminating good products in the prior art.

[0046] As a preferred implementation structure of the utility model, refer to Fig. 9 As shown, in this embodiment, the adhesive-free area extends outward to the edge of the heat dissipation auxiliary sheet 100. In this way, while ensuring that the heat dissipation auxiliary sheet 100 has a better heat dissipation effect, the amount of adhesive used can be reduced to the greatest extent, thereby reducing the production cost of the heat dissipation auxiliary sheet 100.

[0047] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0048] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the utility model. They are not intended to limit the protection scope of the utility model. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A heat dissipation auxiliary sheet for assisting the heat dissipation of a film flip chip packaging structure, characterized in that: The heat dissipation auxiliary sheet includes an insulating protection layer, a first adhesive layer, a heat dissipation film layer and a second adhesive layer which are stacked in sequence from top to bottom. The heat dissipation auxiliary sheet has a chip matching area corresponding to the position of the chip in the thin film chip-on-chip packaging structure. The heat dissipation film layer has a first heat dissipation portion corresponding to the chip matching area and a punching preset portion which is arranged around the first heat dissipation portion and has a shear strength less than the shear strength of the first heat dissipation portion.

2. The heat dissipation auxiliary sheet according to claim 1, characterized in that: The heat dissipation film material layer further comprises a second heat dissipation portion which is arranged around the punching pre-set portion and has a shear strength greater than the shear strength of the punching pre-set portion.

3. The heat dissipation auxiliary sheet according to claim 1, characterized in that: The punching pre-set portion is arranged in a closed shape around the first heat dissipation portion.

4. The heat dissipation auxiliary sheet according to any one of claims 1 to 3, characterized in that: The thickness of the punching pre-set portion is smaller than the thickness of the first heat dissipation portion.

5. The heat dissipation auxiliary sheet according to any one of claims 1 to 3, characterized in that: The punching preset portion is preset with a plurality of through holes or blind holes distributed at intervals.

6. The heat dissipation auxiliary sheet according to any one of claims 1 to 3, characterized in that: The punching preset portion is preset with a cutting groove.

7. The heat dissipation auxiliary sheet according to any one of claims 1 to 3, characterized in that: The heat dissipation film material layer is a metal layer and / or a graphite layer.

8. The heat dissipation auxiliary sheet according to any one of claims 1 to 3, characterized in that: At least one of the first adhesive layer and the second adhesive layer is provided as an adhesive-free area at a position corresponding to the punching preset portion.

9. The heat dissipation auxiliary sheet according to claim 8, characterized in that: The glue-free area extends outward to the edge of the heat dissipation auxiliary sheet.

10. A chip-on-film packaging structure, characterized in that: It includes a chip and a flexible circuit board, wherein the flexible circuit board has a chip bonding area for electrically connecting the chip and a preset bad punching area defined around the chip bonding area; the thin film chip-on-chip packaging structure also has a heat dissipation auxiliary sheet as described in any one of claims 1 to 9 arranged on at least one surface side of the flexible circuit board, and the punching preset portion of the heat dissipation auxiliary sheet corresponds to the position of the preset bad punching area.

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