Press-fit stack-up structure of flexible circuit board and printed circuit board thereof

Abstract

The utility model belongs to the technical field of flexible circuit boards, and particularly relates to a press-fit stack-up structure of a flexible circuit board and a printed circuit board of the press-fit stack-up structure. The utility model relates to a flexible circuit board press-fit stack structure. The press-fit stack structure is sequentially provided with a shielding layer, a flexible circuit board, a conductive supporting layer, a reinforcing layer and a heat conduction layer from top to bottom, a first isolation layer is arranged between the shielding layer and the flexible circuit board, and a second isolation layer is arranged between the conductive supporting layer and the reinforcing layer; the upper layer of the shielding layer is provided with an upper structure supporting layer, and the lower layer of the heat conduction layer is provided with a lower structure supporting layer; a buffer layer is arranged between the reinforcing layer and the heat conduction layer; the reinforcing layer is a steel plate.

Description

Technical Field

[0001] The utility model belongs to the technical field of printed circuit boards, and particularly relates to a lamination structure for pressing a flexible circuit board and a printed circuit board thereof. Background Art

[0002] With the development of modern electronic devices, especially in high-precision electronic products such as smart phones, higher requirements are put forward for the imaging quality of cameras. This includes key indicators such as high-quality photo taking, shallow depth of field, performance under low light conditions, and high zoom ability. To meet these requirements, the size of the photosensitive element is continuously increased, and the sizes of RFPC (rigid-flex printed circuit board) and FPC (flexible printed circuit board) used to support the photosensitive element are also increased accordingly.

[0003] However, with the increase in the sizes of RFPC and FPC, the problem of flatness becomes particularly prominent. The traditional pressing process is difficult to effectively solve the problem of suspension between the conductive adhesive and the steel sheet, which not only affects the overall flatness of RFPC and FPC, but also directly affects the pixel accuracy of the camera module, thereby leading to a decline in imaging quality. Summary of the Invention

[0004] The purpose of the utility model is to solve the above deficiencies and provide a lamination structure for pressing a flexible circuit board and a printed circuit board thereof.

[0005] In the first aspect, a lamination structure for pressing a flexible circuit board adopts the following technical scheme:

[0006] A lamination structure for pressing a flexible circuit board, the lamination structure is sequentially provided with a shielding layer, a flexible circuit board, a conductive support layer, a reinforcing layer, and a heat conduction layer from top to bottom; a first isolation layer is arranged between the shielding layer and the flexible circuit board, and a second isolation layer is arranged between the conductive support layer and the reinforcing layer; an upper structural support layer is arranged on the upper layer of the shielding layer, and a lower structural support layer is arranged on the lower layer of the heat conduction layer; a buffer layer is arranged between the reinforcing layer and the heat conduction layer; the reinforcing layer is a steel plate.

[0007] Further, the shielding layer is a tin-aluminum foil layer.

[0008] Further, the first isolation layer and the second isolation layer are release films.

[0009] Further, the buffer layer is a fiberglass cloth.

[0010] Further, the heat conduction layer is a sintered iron plate.

[0011] Further, the conductive support layer includes a stainless steel layer and a conductive adhesive layer, and the conductive adhesive layer is located between the stainless steel layer and the flexible circuit board.

[0012] Furthermore, the width of the hard-soft transition section between the stainless steel layer and the flexible circuit board is ≤ 0.3 mm and less than the thickness of the conductive adhesive layer.

[0013] Furthermore, for other lamination layers except the stainless steel layer and the flexible circuit board, the width of the hard-soft transition section is ≤ 0.2 mm and less than the thickness of the conductive adhesive layer.

[0014] In a second aspect, a printed circuit board adopts the following technical solution:

[0015] A printed circuit board includes the flexible circuit board lamination stack described above.

[0016] Advantages of the present utility model:

[0017] The present utility model provides a lamination stack for a flexible circuit board. By adopting a hard-to-hard lamination method, the problem of suspension between the conductive adhesive and the steel sheet is effectively solved. By adjusting the lamination stack, the conductive adhesive is evenly distributed during the lamination process, ensuring that it closely adheres to the RFPC / FPC and the steel sheet. This not only greatly improves the flatness of the product but also ensures the good electrical conductivity of the conductive adhesive, enhancing the overall electrical performance and mechanical strength of the product. Description of the Drawings

[0018] Figure 1 It is a schematic structural diagram of the lamination stack of the flexible circuit board for the embodiment;

[0019] Figure 2 It is a schematic structural diagram of the flexible circuit board - conductive support layer;

[0020] Figure 3 It is a schematic diagram of the hard-soft transition section of the flexible circuit board - conductive support layer;

[0021] Reference Numerals: 1. Lamination Stack; 10a. Upper Structural Support Layer; 10b. Lower Structural Support Layer; 20. Shielding Layer; 30. First Isolation Layer; 40. Flexible Circuit Board; 50. Conductive Support Layer; 51. Conductive Adhesive Layer; 52. Stainless Steel Layer; 53. Hard-Soft Transition Section; 60. Second Isolation Layer; 70. Reinforcement Layer; 80. Heat Conduction Layer; 90. Buffer Layer. Detailed Embodiments

[0022] The following combines embodiments to further specifically describe the lamination structure of the flexible circuit board and its printed circuit board according to the present utility model. For the sake of simplicity in description, this document cannot enumerate all alternative technical features and implementation schemes included in the present utility model. Therefore, those skilled in the art should be aware that any technical feature and implementation scheme within this embodiment do not limit the protection scope of the present utility model, and this protection scope includes any alternative technical features and implementation schemes that those skilled in the art can adopt without creative labor. Specifically, implementation schemes obtained by replacing any technical feature in the present utility model or combining any two or more technical features provided by the present utility model should be within the protection scope of the present utility model.

[0023] This embodiment provides a flexible circuit board lamination structure 1, as Figure 1 shown. The lamination structure 1 is sequentially arranged with a shielding layer 20, a flexible circuit board 40, a conductive support layer 50, a reinforcing layer 70, and a heat conduction layer 80 from top to bottom; a first isolation layer 30 is arranged between the shielding layer 20 and the flexible circuit board 40, and a second isolation layer 60 is arranged between the conductive support layer 50 and the reinforcing layer 70; an upper structural support layer 10a is arranged on the upper layer of the shielding layer 20, and a lower structural support layer 10b is arranged on the lower layer of the heat conduction layer 80; a buffer layer 90 is arranged between the reinforcing layer 70 and the heat conduction layer 80; the reinforcing layer 70 is a steel plate.

[0024] This lamination structure 1 sequentially includes multiple functional layers from top to bottom, including a shielding layer 20, a flexible circuit board 40, a conductive support layer 50, a reinforcing layer 70, and a heat conduction layer 80. In order to improve the mutual adaptability between layers, isolation layers and a buffer layer 90 are added to ensure that each layer can perform its expected function during the lamination process. An interlayer reinforcing layer 70 is provided and a steel plate is used, adopting a hard-to-hard lamination method, effectively solving the problem of suspension between the conductive adhesive and the steel sheet. By adjusting the lamination structure, it is ensured that the conductive adhesive is evenly distributed during the lamination process, making it closely adhere to the RFPC / FPC and the steel sheet. This not only greatly improves the flatness of the product but also ensures the good electrical conductivity of the conductive adhesive, enhancing the overall electrical performance and mechanical strength of the product.

[0025] In some embodiments, the shielding layer 20 is a tin-aluminum foil layer.

[0026] By setting the tin-aluminum foil as the shielding layer 20, electromagnetic interference (EMI) is effectively blocked, improving the electrical performance of the entire circuit board, especially providing effective protection against signal interference in high-precision applications such as camera modules.

[0027] In some embodiments, the first isolation layer 30 and the second isolation layer 60 are release films.

[0028] A first isolation layer 30 is provided between the shielding layer 20 and the flexible circuit board 40, and a second isolation layer 60 is provided between the conductive support layer 50 and the reinforcement layer 70. These two isolation films (release films) ensure that the functional layers will not adhere or slide due to material property differences during the lamination process, guaranteeing the independence and stability of each layer.

[0029] In some embodiments, the buffer layer 90 is a fiberglass cloth.

[0030] A buffer layer 90 (fiberglass cloth) is provided between the reinforcement layer 70 and the heat conduction layer 80. This buffer layer 90 can effectively absorb external pressure, prevent structural deformation, and improve the durability of the overall laminated structure at the same time.

[0031] In some embodiments, the heat conduction layer 80 is a baked iron plate.

[0032] In some embodiments, as Figure 1 、 2 shown. The conductive support layer 50 includes a stainless steel layer 52 and a conductive adhesive layer 51, and the conductive adhesive layer 51 is located between the stainless steel layer 52 and the flexible circuit board 40.

[0033] The conductive support layer 50 includes a stainless steel layer 52 and a conductive adhesive layer 51, where the conductive adhesive is located between the stainless steel and the flexible circuit board 40. This design ensures the stability of the conduction path, and the stainless steel layer 52 provides sufficient mechanical strength at the same time.

[0034] In some embodiments, the width of the soft-hard transition section 53 between the stainless steel layer 52 and the flexible circuit board 40 is ≤0.3 mm and less than the thickness of the conductive adhesive layer 51.

[0035] By restricting the width of the soft-hard transition section 53 (≤0.3 mm), the conductive adhesive layer 51 can be evenly distributed and the flexible connection in the edge area can be ensured to be stable.

[0036] In some embodiments, as Figure 3 shown. Except for the stainless steel layer 52 and the flexible circuit board 40, the width of the soft-hard transition section 53 of other laminated layers is ≤0.2 mm and less than the thickness of the conductive adhesive layer 51.

[0037] This embodiment provides a printed circuit board, including the above flexible circuit board lamination stack 1.

[0038] For those of ordinary skill in the art, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation manners here, and the obvious changes or modifications derived therefrom are still within the protection scope of the claims of this utility model.

Claims

1. A flexible circuit board lamination structure, characterized in that, The laminated structure is sequentially provided with a shielding layer, a flexible circuit board, a conductive support layer, a strengthening layer, and a heat conduction layer from top to bottom; a first isolation layer is arranged between the shielding layer and the flexible circuit board, and a second isolation layer is arranged between the conductive support layer and the strengthening layer; an upper structure support layer is arranged on the upper layer of the shielding layer, and a lower structure support layer is arranged on the lower layer of the heat conduction layer; a buffer layer is arranged between the strengthening layer and the heat conduction layer; the strengthening layer is a steel plate.

2. The flexible circuit board lamination structure according to claim 1, wherein The shielding layer is a tin-aluminum foil layer.

3. The flexible circuit board lamination structure according to claim 1, characterized in that The first isolation layer and the second isolation layer are release films.

4. A flexible circuit board lamination structure according to claim 1, wherein The buffer layer is a fiberglass cloth.

5. A flexible circuit board lamination structure according to claim 1, wherein, The heat conduction layer is a sintered iron plate.

6. The flexible circuit board lamination structure according to claim 1, characterized in that The conductive support layer includes a stainless steel layer and a conductive adhesive layer, and the conductive adhesive layer is located between the stainless steel layer and the flexible circuit board.

7. The flexible circuit board lamination structure according to claim 6, wherein The width of the soft-hard transition section between the stainless steel layer and the flexible circuit board is ≤ 0.3 mm and less than the thickness of the conductive adhesive layer.

8. A flexible circuit board lamination structure according to claim 7, wherein, Except for the stainless steel layer and the flexible circuit board, the width of the soft-hard transition section of other laminated layers is ≤ 0.2 mm and less than the thickness of the conductive adhesive layer.

9. A printed circuit board, characterized in that, It includes the flexible circuit board laminated structure according to any one of claims 1-8.

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