Flexible conformal shielding packaging structure

Abstract

The utility model relates to the technical field of electronic devices, and discloses a flexible conformal shielding packaging structure, which comprises a PCB (printed circuit board), a shielding film cover and a conductive connecting piece, and is characterized in that the PCB is provided with a grounding circuit and a chip radiator; the shielding film cover is arranged on the PCB and covers the chip radiator, the shielding film cover and the chip radiator are arranged in a conformal mode, the shielding film cover comprises an elastic insulation supporting layer and an electromagnetic shielding layer which are sequentially arranged in a stacked mode from bottom to top, the thickness of the elastic insulation supporting layer is 50-200 microns, and the thickness of the electromagnetic shielding layer is 50-200 microns. The thickness of the electromagnetic shielding layer is 0.5-10 [mu] m, and the electromagnetic shielding layer is electrically connected with the grounding circuit through the conductive connecting piece. According to the invention, miniaturization and light weight of equipment can be realized.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic devices, in particular to a flexible conformal shielding packaging structure. Background Art

[0002] At present, shielding in electronic systems has two main purposes: one is to comply with electromagnetic compatibility (EMC) regulations, and the other is to protect devices from external electromagnetic interference (EMI). The traditional solution is to install a metal shield on a printed circuit board (PCB).

[0003] With the rapid development of the semiconductor industry, electronic devices are moving towards thinness and high density. The traditional board-level electromagnetic shielding packaging process is to install a metal shield on the PCB board. The metal shield not only takes up a lot of three-dimensional space inside the device, but also has a relatively large weight for some applications (such as drones and wearable devices). Therefore, it has become a major difficulty that hinders the miniaturization and lightweighting of the device. Utility Model Content

[0004] The purpose of the utility model is to provide a flexible conformal shielding packaging structure to effectively reduce the occupation of three-dimensional space and realize the thinning and lightness of the equipment.

[0005] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0006] A flexible conformal shielding packaging structure comprises: a PCB board, a shielding film cover and a conductive connector, wherein the PCB board is provided with a grounding circuit and a chip radiator; the shielding film cover is arranged on the PCB board and covers the chip radiator, and the shielding film cover is arranged conformally with the chip radiator, the shielding film cover comprises an elastic insulating support layer and an electromagnetic shielding layer which are stacked in sequence from bottom to top, the thickness of the elastic insulating support layer is 50-200um, the thickness of the electromagnetic shielding layer is 0.5-10um, and the electromagnetic shielding layer is electrically connected to the grounding circuit through the conductive connector.

[0007] Preferably, the conductive connecting member is solder.

[0008] Preferably, the outer edge of the shielding film cover is bent upward to form a groove in the area of ​​the shielding film cover close to the outer edge, and the groove is provided with a plurality of welding holes along its circumference that pass through the upper and lower sides of the shielding film cover. One end of the solder material is welded in the groove, and the other end of the solder material passes through the welding hole and is welded to the grounding circuit.

[0009] Preferably, the groove is a wedge-shaped groove which is wider at the top and narrower at the bottom, and the welding hole is located at the bottom of the wedge-shaped groove.

[0010] Preferably, the width of the bottom of the wedge-shaped groove is not less than 0.5 mm.

[0011] Preferably, the outer edge of the shielding film cover is bent upward by no less than 0.5 mm.

[0012] Preferably, a temporary fixing adhesive film layer is further included, and the temporary fixing adhesive film layer is arranged between the shielding film cover and the PCB board to temporarily fix the shielding film cover on the PCB board.

[0013] Preferably, the temporary fixing adhesive film layer is made of EVA hot melt adhesive film, PES hot melt adhesive film or acrylic pressure sensitive adhesive.

[0014] Preferably, the elastic insulating support layer is made of PE I or PI.

[0015] Preferably, the electromagnetic shielding layer is formed by stacking Ni and one or more materials selected from Sn, Cu or Au, and the bottom layer of the electromagnetic shielding layer is made of Ni material.

[0016] Compared with the prior art, the flexible conformal shielding packaging structure of the embodiment of the utility model has the following beneficial effects:

[0017] In the present invention, a shielding film cover is installed on the PCB board and covers the chip radiator to prevent the chip radiator from being interfered by external electromagnetic waves. The shielding film cover is conformally arranged with the chip radiator, that is, the inner side of the shielding film cover is close to the chip radiator. At the same time, the shielding film cover includes an elastic insulating support layer and an electromagnetic shielding layer stacked from bottom to top. The thickness of the elastic insulating support layer is 50-200um, and the thickness of the electromagnetic shielding layer is 0.5-10um. Compared with the metal shielding cover of the prior art, the present application can effectively reduce the height of the packaging structure, reduce the occupation of the three-dimensional space, and is lighter in weight, thereby realizing the miniaturization and lightweight of the equipment. At the same time, it should be noted that the optimal thickness of the electromagnetic shielding layer is 0.5-10um. If the thickness of the electromagnetic shielding layer is less than 0.5um, it is difficult to ensure the shielding effect. If the thickness of the electromagnetic shielding layer is greater than 10um, it will increase the cost and easily cause cracking. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model;

[0019] Figure 2 It is a top view of the shielding film cover according to an embodiment of the utility model.

[0020] In the figure, 1, PCB board; 11, grounding circuit; 12, chip radiator; 2, shielding film cover; 21, elastic insulating support layer; 22, electromagnetic shielding layer; 23, groove; 24, welding hole; 3, conductive connector; 4, temporary fixing film layer. DETAILED DESCRIPTION

[0021] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0022] In the description of the present utility model, it should be understood that the wording "comprising" used in the present utility model specification refers to the presence of the features, integers, steps, operations, parts / components and / or assemblies, but does not exclude the presence or addition of one or more other features, integers, steps, operations, parts / components, assemblies and / or their groups. It should be understood that when we say that a part / component is "connected" to another part / component, it can be directly connected to the other part / component, or there can be intermediate parts / components. The wording "and / or" used here includes all or any unit and all combinations of one or more associated listed items.

[0023] like Figure 1 and Figure 2 As shown, the utility model relates to a flexible conformal shielding packaging structure, comprising: a PCB board 1, a shielding film cover 2 and a conductive connector 3, wherein the PCB board 1 is provided with a grounding circuit 11 and a chip radiator 12; the shielding film cover 2 is arranged on the PCB board 1, and covers the chip radiator 12, and the shielding film cover 2 is conformally arranged with the chip radiator 12, the shielding film cover 2 comprises an elastic insulating support layer 21 and an electromagnetic shielding layer 22 which are stacked in sequence from bottom to top, the thickness of the elastic insulating support layer 21 is 50-200um, the thickness of the electromagnetic shielding layer 22 is 0.5-10um, and the electromagnetic shielding layer 22 is electrically connected to the grounding circuit 11 through the conductive connector 3.

[0024] In the utility model, a shielding film cover 2 is installed on the PCB board 1 and covers the chip radiator 12 to prevent the chip radiator 12 from being interfered by external electromagnetic waves. The shielding film cover 2 is conformally arranged with the chip radiator 12, that is, the inner side of the shielding film cover 2 is close to the chip radiator 12. At the same time, the shielding film cover 2 includes an elastic insulating support layer 21 and an electromagnetic shielding layer 22 stacked in sequence from bottom to top. The thickness of the elastic insulating support layer 21 is 50-200um, and the thickness of the electromagnetic shielding layer 22 is 0.5-10um. Therefore, compared with the metal shielding cover in the prior art, the present application can effectively reduce the height of the packaging structure, reduce the occupation of the three-dimensional space, and is lighter in weight, thereby realizing the miniaturization and lightweight of the equipment. Meanwhile, it should be noted that the optimal thickness of the electromagnetic shielding layer 22 is 0.5-10um. If the thickness of the electromagnetic shielding layer 22 is less than 0.5um, it is difficult to ensure the shielding effect. If the thickness of the electromagnetic shielding layer 22 is greater than 10um, it will increase the cost and easily cause cracking.

[0025] In this embodiment, the conductive connector 3 is a solder material, so as to weld and fix the shielding film cover 2 on the PCB board 1. At the same time, one end of the solder material contacts the electromagnetic shielding layer 22, and the other end contacts the grounding circuit 11, so that the electromagnetic shielding layer 22 is electrically connected to the grounding circuit 11 to form a Faraday cage.

[0026] Preferably, the outer edge of the shielding film cover 2 is bent upward to form a groove 23 in the area near the outer edge of the shielding film cover 2, and the groove 23 is discretely opened along its circumference with a plurality of welding holes 24 that pass through the upper and lower sides of the shielding film cover 2. One end of the solder material is welded in the groove 23 and contacts the electromagnetic shielding layer 22, and the other end of the solder material passes through the welding hole 24 and is welded and fixed to the grounding circuit 11.

[0027] Specifically, the groove 23 is a wedge-shaped groove that is wide at the top and narrow at the bottom. The welding hole 24 is located at the bottom of the wedge-shaped groove. The width of the bottom of the wedge-shaped groove is not less than 0.5 mm. The outer edge of the shielding film cover 2 is bent upward by not less than 0.5 mm. The solder in the wedge-shaped groove is welded and fixed to the bottom and side surfaces of the electromagnetic shielding layer 22 in the wedge-shaped groove, thereby increasing the contact area between the solder and the electromagnetic shielding layer 22 to enhance the connection stability and ensure the stability of the shielding film cover 2 on the PCB board 1. At the same time, it also ensures the stability of the electrical connection between the electromagnetic shielding layer 22 and the grounding circuit 11.

[0028] In this embodiment, the present application performs laser solder ball welding or laser BGA solder ball implantation on the welding hole 24 to connect the electromagnetic shielding layer 22 and the grounding circuit 11 with the solder material. The welding method is simpler. Since the position of the solder material welding is located and captured according to the position of the welding hole 24 opened in advance, the positioning accuracy of the shielding film cover 2 and the opening accuracy of the welding hole 24 are relatively low, which is beneficial to improving the yield of the product.

[0029] In this embodiment, the flexible conformal shielding packaging structure also includes a temporary fixing film layer 4, which is arranged between the shielding film cover 2 and the PCB board 1 to temporarily fix the shielding film cover 2 on the PCB board 1, so that the shielding film cover 2 is pre-fixed on the PCB board 1 by the temporary fixing film layer 4, and then the shielding film cover 2 can be conveniently welded to the PCB board 1 by the solder material.

[0030] Specifically, the temporary fixing adhesive film layer 4 is made of EVA hot melt adhesive film, PES hot melt adhesive film or acrylic pressure-sensitive adhesive. Therefore, when pre-fixing the shielding film cover 2, if the temporary fixing adhesive film layer 4 is EVA hot melt adhesive film or PES hot melt adhesive film, the shielding film cover 2 and the PCB board 1 are bonded together by heating the EVA hot melt adhesive film or PES hot melt adhesive film. If the temporary fixing adhesive film layer 4 is acrylic pressure-sensitive adhesive, the shielding film cover 2 and the PCB board 1 are bonded together by pressing, so that the shielding film cover 2 can be pre-fixed on the PCB board 1, which is convenient for the subsequent welding of the shielding film cover 2 on the PCB board 1 through the solder material.

[0031] In this embodiment, the elastic insulating support layer 21 is made of PE I or PI. Preferably, the elastic insulating support layer 21 is made of PE I. The density of the PE I material is 1.27 g / m3, while the density of the tinplate of the metal shielding cover in the prior art is 7.8 g / m3. Therefore, the density of the elastic insulating support layer 21 of the present application is much lower than the density of the tinplate of the metal shielding cover in the prior art, which is conducive to lightweight. At the same time, the PE I material has high rigidity and high impact resistance, which can provide better protection for the chip radiator 12.

[0032] In this embodiment, the electromagnetic shielding layer 22 is formed by stacking Ni and one or more materials of Sn, Cu or Au, and the bottom layer of the electromagnetic shielding layer 22 is made of Ni material. Therefore, compared with the existing metal shielding cover, the electromagnetic shielding layer 22 contains less Ni and Fe magnetic elements, thereby reducing the interference of other magnetic sensitive devices.

[0033] In summary, compared with the prior art, the flexible conformal shielding packaging structure of the present invention has the following technical effects:

[0034] 1. The shielding film cover of the present application includes an elastic insulating support layer and an electromagnetic shielding layer stacked together, so that the shielding film cover has a certain elasticity, and a plurality of solder materials are discretely distributed and connect the shielding film cover and the PCB board, so that when the PCB board encounters vibration or thermal expansion deformation, the shielding film cover can adapt to a certain deformation, and thus can maintain good contact with the PCB board.

[0035] 2. The elastic insulating support layer is made of PE I material, which has good impact resistance and can protect the chip radiator. It also has low density, which is conducive to lightweighting of the device.

[0036] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A flexible conformal shielding packaging structure, characterized in that: include: A PCB board, a shielding film cover and a conductive connector, wherein the PCB board is provided with a grounding circuit and a chip radiator; the shielding film cover is arranged on the PCB board and covers the chip radiator, and the shielding film cover is conformally arranged with the chip radiator, the shielding film cover comprises an elastic insulating support layer and an electromagnetic shielding layer which are stacked in sequence from bottom to top, the thickness of the elastic insulating support layer is 50-200um, the thickness of the electromagnetic shielding layer is 0.5-10um, and the electromagnetic shielding layer is electrically connected to the grounding circuit through the conductive connector.

2. The flexible conformal shielding packaging structure according to claim 1, characterized in that: The conductive connecting member is solder material.

3. The flexible conformal shielding packaging structure according to claim 2, characterized in that: The outer edge of the shielding film cover is bent upward to form a groove in the area near the outer edge of the shielding film cover, and the groove is provided with a plurality of welding holes along its circumference that pass through the upper and lower sides of the shielding film cover. One end of the solder material is welded in the groove, and the other end of the solder material passes through the welding hole and is welded to the grounding circuit.

4. The flexible conformal shielding packaging structure according to claim 3, characterized in that: The groove is a wedge-shaped groove which is wide at the top and narrow at the bottom, and the welding hole is located at the bottom of the wedge-shaped groove.

5. The flexible conformal shielding packaging structure according to claim 4, characterized in that: The width of the bottom of the wedge-shaped groove is not less than 0.5 mm.

6. The flexible conformal shielding packaging structure according to claim 3, characterized in that: The outer edge of the shielding film cover is bent upward by no less than 0.5 mm.

7. The flexible conformal shielding packaging structure according to claim 1, characterized in that: It also includes a temporary fixing film layer, which is arranged between the shielding film cover and the PCB board to temporarily fix the shielding film cover on the PCB board.

8. The flexible conformal shielding packaging structure according to claim 7, characterized in that: The temporary fixing adhesive film layer is made of EVA hot melt adhesive film, PES hot melt adhesive film or acrylic pressure sensitive adhesive.

9. The flexible conformal shielding packaging structure according to claim 1, characterized in that: The elastic insulating support layer is made of PEI or PI.

10. The flexible conformal shielding packaging structure according to claim 1, characterized in that: The electromagnetic shielding layer is formed by stacking Ni and one or more materials selected from Sn, Cu or Au, and the bottom layer of the electromagnetic shielding layer is made of Ni material.

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