An electromagnetic shielding device and related method

Abstract

Embodiments of the present application disclose an electromagnetic shielding device and related methods. The electromagnetic shielding device includes: a wire arc structure, a wire column structure, and a metal shielding layer. Among them, the wire arc structure, the wire column structure, and the metal shielding layer are all metal conductors. One end of the wire column structure is connected to the endpoint of the wire arc structure, and the other end of the wire column structure is connected to the metal shielding layer. This electromagnetic shielding device is applied to cavity electromagnetic shielding, does not require an increase in device height, and reduces the volume of electronic components.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of electromagnetic shielding, and in particular, to an electromagnetic shielding device and related methods. Background Art

[0002] With the development of electronic devices, electronic components tend to be miniaturized and integrated. A large number of components inside consumer electronics such as mobile phones, watches, and earphones adopt (system in package, SIP) packaging integration to improve the high-density layout of products. Among them, the component units (such as radio frequency components) inside SIP need to use cavity electromagnetic shielding technology to solve the problem of mutual interference inside the SIP module.

[0003] The electromagnetic shielding device using the wire arc process can play a certain high-frequency shielding role and has advantages such as low cost and high efficiency. Refer to Figure 1 which is an existing electromagnetic shielding device using the wire arc process, forming a Faraday cage around the component unit to achieve the effect of cavity shielding.

[0004] However, the wire arc of the metal wire increases the height of the device, which is not conducive to high-density integrated layout. Summary of the Invention

[0005] A first aspect of embodiments of the present application provides an electromagnetic shielding device, including:

[0006] A wire arc structure, a wire column structure, and a metal shielding layer; wherein, the wire arc structure, the wire column structure, and the metal shielding layer are all metal conductors; one end of the wire column structure is connected to the endpoint of the wire arc structure, and the other end of the wire column structure is connected to the metal shielding layer.

[0007] Embodiments of the present application provide an electromagnetic shielding device that can be applied to cavity electromagnetic shielding, does not require increasing the height of the device, and reduces the volume of electronic components.

[0008] Based on the first aspect of embodiments of the present application, in the first implementation manner of the first aspect of embodiments of the present application, the wire arc structure includes two or more sub-wire arc structures, and the endpoints of each group of sub-wire arc structures are connected.

[0009] In embodiments of the present application, an implementation manner of forming a wire arc structure with multiple sub-wire arc structures is provided, improving the electromagnetic shielding effect.

[0010] Based on the first aspect or the first implementation manner of the first aspect of embodiments of the present application, in the second implementation manner of the first aspect of embodiments of the present application, a packaging system is provided. The packaging system includes an electromagnetic shielding structure, a substrate, and two or more component units, wherein the endpoint of the wire arc structure is connected to the substrate, and the component units are separated by the electromagnetic shielding structure.

[0011] In an embodiment of the present application, a packaging system is provided. This packaging system can package component units to achieve the effect of cavity separation and shielding.

[0012] Based on the second implementation manner of the first aspect of the embodiments of the present application, in the third implementation manner of the first aspect of the embodiments of the present application, the component unit is a chip.

[0013] The embodiments of the present application can be used for chip packaging.

[0014] Based on the second implementation manner or the third implementation manner of the first aspect of the embodiments of the present application, in the fourth implementation manner of the first aspect of the embodiments of the present application, the stud structure is perpendicular to the substrate and perpendicular to the top layer of the metal shielding layer.

[0015] The embodiments of the present application provide a deployment state of the stud structure, improving the feasibility of the solution.

[0016] Based on any one of the second to fourth implementation manners of the first aspect of the embodiments of the present application, in the fifth implementation manner of the first aspect of the embodiments of the present application, the substrate may include metal traces and pads, and the pads include ground pads.

[0017] Based on any one of the second to fifth implementation manners of the first aspect of the embodiments of the present application, in the sixth implementation manner of the first aspect of the embodiments of the present application, the wire arc structure, the stud structure, and the shielding layer are connected through a slot hole structure and / or a film adding structure.

[0018] In the embodiments of the present application, multiple connection methods are provided, improving the flexibility of the solution.

[0019] Based on any one of the second to sixth implementation manners of the first aspect of the embodiments of the present application, in the seventh implementation manner of the first aspect of the embodiments of the present application, the electromagnetic shielding device includes stainless steel, copper, nickel, and / or aluminum.

[0020] The second aspect of the embodiments of the present application provides a packaging method, including:

[0021] Mounting component units on a substrate, where the number of the component units is two or more, and packaging an electromagnetic shielding device for reducing electromagnetic interference between the component units, and the electromagnetic shielding device is the electromagnetic shielding device shown in any embodiment of the first aspect of the present application. Description of the Drawings

[0022] Figure 1 It is an electromagnetic shielding device in the embodiments of the present application;

[0023] Figure 2It is a packaging system for an electromagnetic shielding device in an embodiment of the present application;

[0024] Figure 3 It is another electromagnetic shielding device in an embodiment of the present application;

[0025] Figure 4 It is a packaging system for another electromagnetic shielding device in an embodiment of the present application;

[0026] Figure 5 It is another electromagnetic shielding device in an embodiment of the present application;

[0027] Figure 6 It is a schematic diagram showing the relationship between conductor density and shielding effectiveness in an embodiment of the present application;

[0028] Figure 7 It is another electromagnetic shielding device in an embodiment of the present application;

[0029] Figure 8 It is another electromagnetic shielding device in an embodiment of the present application;

[0030] Figure 9 It is another electromagnetic shielding device in an embodiment of the present application;

[0031] Figure 10 It is another electromagnetic shielding device in an embodiment of the present application;

[0032] Figure 11 It is another electromagnetic shielding device in an embodiment of the present application. Detailed implementation manners

[0033] An embodiment of the present application provides an electromagnetic shielding device, which can be applied to cavity electromagnetic shielding.

[0034] Refer to Figure 1 , an embodiment of the present application provides an electromagnetic shielding device, including:

[0035] A wire arc structure, a wire column structure and a metal shielding layer.

[0036] Refer to Figure 2 , for the packaging system based on the Figure 1 shown electromagnetic shielding device, the packaging system includes an electromagnetic shielding structure, a substrate and two or more component units.

[0037] The following is an explanation of the packaging method:

[0038] Prepare a substrate, which includes at least one layer of metal wiring layer, solder pads, and at least one ground solder pad in the solder pads.

[0039] Mount electronic components on the surface of the substrate. The electronic components include various active and passive devices, chips, isolated components or component packages.

[0040] In the design signal isolation area between two or more components, a first continuous wire arc that is multi-point coupled to the printed circuit board (PCB) pads is implanted using the wire bonding process. Wire bonding is a process that uses a thin metal wire and utilizes heat, pressure, and ultrasonic energy to tightly bond the metal lead to the substrate pad. In this embodiment, copper wire is preferably used. The diameter of the copper wire can be 30 micrometers (μm), the diameter of the pad at the bottom of the copper wire column is 70 μm, and the height of the wire arc is not higher than the height of the encapsulant of the entire system-level package. The possible height range is ≥0.1 millimeter (mm). It can be understood that other metal wires, such as aluminum, silver, etc., can also be used. The diameter of the metal wire is determined according to the specific actual scenario and is not limited in the embodiments of this application.

[0041] At the coupling points between the wire arc structure and the pads, metal wire columns are vertically stacked and implanted using the wire bonding process. In this embodiment, it is preferably coupled with the above-mentioned copper wire and copper column on the multi-point continuous wire arc to form a stacked structure, increasing the high-density layout and wire density. The height of the copper column is slightly lower than the height of the encapsulant, such as 50 - 300 μm lower.

[0042] This structure is encapsulated with an insulating material. The insulating material wraps the electronic components and the copper wire column structure. The insulating layer material can be epoxy resin, acrylic resin material, dielectric material, thermosetting material, thermoplastic material, rubber, or other insulating materials. Usually, the injection process is used to form the insulating layer in the molding tool.

[0043] In the copper wire arc and column areas, a structure of grooves or holes is etched using a laser. In this embodiment, laser cutting can be used. Laser cutting uses a focused high-power density laser beam to irradiate the workpiece, causing the irradiated material to quickly melt, vaporize, ablate, or reach the ignition point. At the same time, the molten material is blown away by a high-speed gas flow coaxial with the beam, thereby realizing cutting the workpiece. Based on the sensitivity of different materials to the absorption of laser energy of different wavelengths, selective grooving can be achieved. In this embodiment, it is possible to selectively remove only the insulating material while leaving the copper structure intact. The width of the groove can be 50 μm to 300 μm, the diameter of the hole can be 50 μm to 300 μm, and the size of the grooving or hole opening is based on exposing the upper surface part of the copper wire column.

[0044] A shielding layer is attached to the upper surface and side walls of the entire system-level package. Electrical conductivity between the copper wire column and the shielding layer is achieved. In this embodiment, the process that can be used is physical sputtering deposition. The main structure is a single-layer or multi-layer structure of a stainless steel layer and a copper layer. Other depositable metal materials are selected as copper, nickel, and aluminum. The metal shielding layer will be realized. Chemical vapor deposition of metals, electroplating, and other methods can also be used to realize the shielding layer structure.

[0045] The above is only a possible implementation of the encapsulation method. The electromagnetic shielding device can implant an arc structure that is multi-point coupled with the PCB pads in the sub-cavity area by wire bonding technology; and implant metal pillars at the coupling points between the arc structure and the PCB pads by the vertical stacking process of wire bonding.

[0046] See Figure 3 , it can be understood that other processes can also be used to implant the pillars, which are not limited here. For example, when encapsulating with an insulating material, a film can be added in the mold cavity to bury the arc structure in the film, and after plastic encapsulation, the end of the pillar is exposed. See Figure 4 for the corresponding encapsulation system.

[0047] It can be understood that the pillar structure can be perpendicular to the substrate (such as Figure 1 , Figure 3 ), or at other angles. See Figure 5 . In the embodiments of the present application, the vertical example is used for illustration.

[0048] In the embodiments of the present application, a multi-point coupled continuous arc structure is adopted. The number of grounding points of the arc increases, improving the ground conductivity. The continuous coupling eliminates the spacing between different arcs in the multi-arc process of the wire bonding technology, increasing the conductor density. Adding pillars can also increase the arc density. Figure 6 is a schematic diagram of the relationship between conductor density and shielding effectiveness. As the conductor density of WB1 - WB3 increases, the shielding effectiveness increases. NoWB is when there is no conductor.

[0049] See Figure 7 , the arc structure can include multiple groups of sub-arc structures. The second continuous arc is vertically stacked and implanted at the coupling point between the first continuous arc and the grounding pad by wire bonding technology; the height of the second arc is higher than that of the first arc, and metal pillars are vertically stacked and implanted at the coupling point between the second continuous arc and the first continuous arc by wire bonding technology; adopting multiple groups of sub-arc structures increases the conductor density, thereby increasing the shielding effectiveness.

[0050] See Figure 8 and Figure 9 , the embodiments of the present application provide an implementation manner where adjacent arcs are not connected. In the embodiments of the present application, multiple groups of sub-arc structures may not be completely symmetrical. See Figure 10 for a possible electromagnetic shielding structure.

[0051] It can be understood that in some cases, the pillar structure can be removed and multiple groups of sub-arc structures can be adopted. See Figure 11 .

[0052] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated here.

[0053] In several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling, direct coupling, or communication connection to each other can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be in electrical, mechanical, or other forms.

[0054] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0055] In addition, in each embodiment of the present application, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0056] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application. The foregoing storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROM, read-only memory), random access memories (RAM, random access memory), magnetic disks, or optical discs and other various media that can store program codes.

Claims

1. An electromagnetic shielding device, characterized in that, the electromagnetic shielding device is used for encapsulating a system, the encapsulating system includes a plurality of pads, and the electromagnetic shielding device includes: a wire arc structure, a wire column structure and a metal shielding layer; the wire arc structure, the wire column structure and the metal shielding layer are all metal conductors; one end of the wire column structure is connected to the end point of the wire arc structure, the wire arc structure is a continuous wire arc structure, the continuous wire arc structure is multi-point coupled with the plurality of pads, and the other end of the wire column structure is connected to the metal shielding layer.

2. The electromagnetic shielding device according to claim 1, characterized in that, the wire arc structure includes two or more sub-wire arc structures, and the end points of each group of sub-wire arc structures are connected.

3. The electromagnetic shielding device according to claim 1 or 2, characterized in that, the encapsulating system includes: a substrate and two or more component units; the end point of the wire arc structure is connected to the substrate; each of the component units is separated by the electromagnetic shielding device.

4. The electromagnetic shielding device according to claim 3, characterized in that, the component unit is a chip.

5. The electromagnetic shielding device according to claim 3, characterized in that, the wire column structure is perpendicular to the substrate and perpendicular to the top layer of the metal shielding layer.

6. The electromagnetic shielding device according to claim 3, characterized in that, the substrate includes metal traces and pads, and the pads include ground pads.

7. The electromagnetic shielding device according to claim 3, characterized in that, the wire arc structure, the wire column structure and the shielding layer are connected through a slot hole structure and / or a film adding structure.

8. The electromagnetic shielding device according to claim 3, characterized in that, the electromagnetic shielding device includes stainless steel, copper, nickel and / or aluminum.

9. A packaging method, characterized in that, comprising: mounting component units on a substrate, the number of the component units being two or more, and the substrate including a plurality of pads; encapsulating an electromagnetic shielding device, the electromagnetic shielding device being used for reducing electromagnetic interference between the component units; the electromagnetic shielding device includes a wire arc structure, a wire column structure and a metal shielding layer; the wire arc structure, the wire column structure and the metal shielding layer are all metal conductors; one end of the wire column structure is connected to the end point of the wire arc structure, the wire arc structure is a continuous wire arc structure, the continuous wire arc structure is multi-point coupled with the plurality of pads, and the other end of the wire column structure is connected to the metal shielding layer.

10. The method according to claim 9, characterized in that, the component unit is a chip.

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