Circuit board assembly, method of manufacturing the same, and electronic device

Abstract

This application provides a circuit board assembly and its manufacturing method, as well as an electronic device, relating to the field of electronic equipment technology. The circuit board assembly includes a circuit board and a heat dissipation shielding structure. Electronic components on the circuit board include a first component and a second component. The heat-generating area of ​​the first component is larger than that of the second component. The width-to-depth ratio of the first gap area is less than or equal to 1:2. The heat dissipation shielding structure includes an insulating film and a shielding film. The insulating film covers all areas in the first region except for the top surface of the first component, the ground terminal, and the first gap area. The insulating film is designed to vary in height according to the electronic components. The shielding film covers the top surface of the first component, the ground terminal, the first gap area, and the side of the insulating film facing away from the circuit board. The shape of the shielding film matches the shapes of the electronic components and the insulating film. The shielding film is electrically connected to the ground terminal. This provides better shielding and heat dissipation for the electronic components, resulting in better performance of the electronic device.

Description

Technical Field

[0001] This application relates to the field of electronic equipment technology, and in particular to a circuit board assembly and its manufacturing method, and an electronic device. Background Technology

[0002] As electronic devices become increasingly functional, the number of electronic components on their internal circuit boards also increases. During the operation of electronic devices, due to continuous and intermittent changes in operating voltage and current, some electronic components generate electromagnetic waves, which may cause electromagnetic interference (EMI) to other electronic components. At the same time, electromagnetic waves from the external environment of electronic devices can also easily generate EMI for electronic components. Therefore, electromagnetic shielding is necessary to reduce electromagnetic interference and radiation to the protected target.

[0003] Currently, various methods are being explored for electromagnetic wave shielding, such as using a metal casing as a shield to cover the target to meet electromagnetic wave shielding requirements.

[0004] However, electronic components generate heat during operation. Because the electronic components are completely covered by a shield, the heat accumulates inside the shield and cannot dissipate. As the operating time increases, more and more heat accumulates inside the shield. This heat damages the performance and lifespan of the electronic components, which in turn seriously affects the performance and lifespan of the electronic equipment. Summary of the Invention

[0005] This application provides a circuit board assembly and its manufacturing method, as well as an electronic device, which can achieve better shielding of electronic components on the circuit board assembly while also improving the heat dissipation effect of the electronic components, thereby improving the working stability and safety of the circuit board assembly.

[0006] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0007] In a first aspect, a circuit board assembly is provided, comprising a circuit board and a heat dissipation shielding structure. The circuit board has a mounting surface, which includes a first region. Various electronic components and the heat dissipation shielding structure are mounted in the first region. The electronic components include at least two adjacent first and second components. The heat dissipation range of the first component is greater than that of the second component. The first and second components are separate and spaced apart. The space between the first and second components includes a first spacer region, the width-to-depth ratio of which is less than or equal to 1:2. The heat dissipation shielding structure includes an insulating film and a shielding film. The insulating film covers all locations except for the top surface of the first component away from the mounting surface and at least a portion of its side surface connected to the top surface, a ground terminal, and the first spacer region. The insulating film is designed to vary in height according to the electronic components. The shielding film covers the top surface of the first component away from the mounting surface and at least a portion of its side surface connected to the top surface, a ground terminal, the first spacer region, and the side of the insulating film facing away from the circuit board. The shape of the shielding film matches the shapes of the electronic components and the insulating film. The shielding film is electrically connected to the ground terminal.

[0008] This application provides a circuit board assembly. By attaching an insulating film to the surface of the circuit board and some electronic components, insulation isolation between adjacent electronic components and the shielding film can be achieved. At the same time, since the shielding film is directly attached to the grounding terminal, the first gap area, part of the insulating film, and the surface of the high-heat-generating device, and the shielding film is connected to the grounding terminal of the circuit board, a Faraday cage is formed to provide good electromagnetic shielding for the electronic components and to provide good heat dissipation. Furthermore, since the insulating film and the shielding film can vary with the height of the electronic components, the heat from the high-heat-generating device can be quickly transferred to the shielding film, improving heat dissipation efficiency and reducing the thickness of the circuit board assembly. This results in miniaturization and thinning of the electronic device, and the electronic device has better performance.

[0009] In one possible implementation of the first aspect, the spacer between the first device and the second device further includes a second spacer, the width-to-depth ratio of the second spacer being greater than 1:2, and the insulating film also covers the second spacer.

[0010] In this implementation, the insulating film can effectively cover the area with a large aspect ratio between adjacent electronic components, achieving insulation isolation between the electronic components and reducing the risk of short circuits.

[0011] In one possible implementation of the first aspect, the first region is further provided with a partition, at least one partition is provided in the first interval region and / or the second interval region, the partition is not in contact with either the first device or the second device, the insulating film does not cover the top surface of the partition away from the mounting surface, the shielding film also covers at least part of the top surface of the partition, and the partition is electrically connected to the shielding film and the mounting surface respectively.

[0012] In this implementation, the electromagnetic shielding of two adjacent electronic components can be effectively achieved through the use of ribs.

[0013] In one possible implementation of the first aspect, a partition is provided in the spacer area between the first device and the second device, the insulating film covers at least the top surface of the second device away from the mounting surface and the side of the second device away from the partition, and the shielding film covers at least the top surface of the first device, the top surface of the partition and a portion of the side surface connected to the top surface, the surface of the insulating film away from the circuit board, and a portion of the mounting surface.

[0014] In this implementation, the partition is set in the first gap area between the first device and the second device. At this time, the partition and the shielding cover together isolate the first device and the second device into their respective flange cages. The partition and the shielding cover are connected to form vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device and the second device, resulting in better performance of the circuit board assembly.

[0015] In one possible implementation of the first aspect, a partition rib is provided in the spacer area between the first device and the second device, and an insulating film covers at least the side of the partition rib away from the first device, the top surface of the second device, and the side of the second device away from the partition rib. A shielding film covers at least the top surface of the first device away from the mounting surface, the top surface of the partition rib, the side of the insulating film away from the circuit board, and part of the mounting surface.

[0016] In this implementation, a partition is set in the first gap area between the first device and the second device. At this time, the partition and the shielding cover together isolate the first device and the second device into their respective flange cages. The partition and the shielding cover are connected to form vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device and the second device. In addition, the insulating film on the side of the partition is connected to the insulating film on the second device. The insulating film can not only provide good insulation and isolation between the first device and the second device, but also support the shielding film, reducing the risk of shielding film breakage. The performance of the circuit board assembly is better.

[0017] In one possible implementation of the first aspect, a partition rib is provided in the spacer area between the first device and the second device, the insulating film covers at least the surface of the second device except for the bottom surface connected to the mounting surface, and the shielding film covers at least the top surface of the first device, the top surface of the partition rib and a portion of the side surface connected to the top surface, the side of the insulating film away from the circuit board, and a portion of the mounting surface.

[0018] In this implementation, the partition is set in the first gap area between the first device and the second device. At this time, the partition and the shielding cover together isolate the first device and the second device into their respective flange cages. The partition and the shielding cover are connected to form vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device and the second device, resulting in better performance of the circuit board assembly.

[0019] In one possible implementation of the first aspect, the electronic component further includes a third component adjacent to the first component. The third component is disposed on the side of the first component away from the second component. The third component is separate from and spaced apart from the first component. The heat generation range of the third component is the same as that of the first component, but the heat generation of the third component is less than that of the first component. A partition rib is provided in the spacer area between the first component and the second component. A partition rib is provided in the spacer area between the first component and the third component. An insulating film covers at least the side of the partition rib between the first component and the second component away from the first component, the top surface of the second component away from the mounting surface, and the side of the second component away from the partition rib. A shielding film covers at least the top surface of the first component, the top surfaces of the two partition ribs, the side of the insulating film away from the partition rib, the side of the insulating film away from the circuit board, and part of the mounting surface.

[0020] In this implementation, partitions are provided between the first and second devices and between the first and third devices. The partitions and the shielding cover together isolate the first, second, and third devices into their respective flange cages. The partitions and the shielding cover are connected to form vertical electromagnetic shielding, which can provide good electromagnetic shielding and heat dissipation for the first, second, and third devices, resulting in good performance of the circuit board assembly.

[0021] In one possible implementation of the first aspect, the material of the rib is metal; or, the material of the rib includes carbon fiber and metal, with the metal wrapped around the surface of the carbon fiber; or, the material of the rib includes resin and metal, with the metal wrapped around the surface of the resin; or, the material of the rib includes copper-clad laminate and resin and copper layers disposed on symmetrical sides of the copper-clad laminate, with the resin layer located between two adjacent copper layers.

[0022] In this implementation method, conductivity can be achieved through the ribs and the shielding membrane, and it is simple and easy to implement.

[0023] In one possible implementation of the first aspect, the heat dissipation shielding structure further includes a base coating layer, which is disposed at least between the top surface of the first device and the shielding film, and the material of the base coating layer is different from the material of the shielding film.

[0024] In this implementation, by providing a base coating between at least one surface of the high-heat-generating device without an insulating film and the shielding film, the heat dissipation of the high-heat-generating device can be improved and the adhesion of the shielding film can be enhanced through the buffering, oxidation resistance, breakdown resistance and corrosion resistance properties of the base coating.

[0025] In one possible implementation of the first aspect, when the material of the primer coating is aluminum, the thickness of the primer coating perpendicular to the mounting surface is 0.02 μm to 1.5 μm; when the material of the primer coating is copper, the thickness of the primer coating perpendicular to the mounting surface is 0.05 μm to 5 μm; and when the material of the primer coating is a nickel-gold alloy or a nickel-palladium-gold alloy, the thickness of the primer coating perpendicular to the mounting surface is 0.02 μm to 1 μm.

[0026] In this implementation, the base coating is thinner, which can better improve the heat dissipation of high-heat-generating devices and enhance the adhesion of the shielding film.

[0027] In one possible implementation of the first aspect, the heat dissipation shielding structure further includes a graphite film covering the side of the shielding film away from the circuit board.

[0028] In this implementation, the heat dissipation effect of the graphite film allows heat dissipation surfaces to be formed on both the side of the graphite film away from the shielding film and the side surface of the graphite film. This allows the heat from the shielding film corresponding to the electronic components to be quickly dispersed to the surface of the graphite, thereby reducing the local temperature of the shielding film, avoiding the generation of hot and cold spots, improving the heat dissipation effect on the electronic components, reducing the generation of thermal stress, and preventing the shielding film from deforming.

[0029] In one possible implementation of the first aspect, the heat dissipation shielding structure further includes a thermally conductive gel disposed between at least a portion of the shielding film and the graphite film.

[0030] In this implementation, by setting a thermally conductive condenser between the shielding film and the graphite film, the thermal conductivity of the thermally conductive gel is greater than that of air, thereby improving the heat transfer efficiency and further enhancing the heat dissipation effect.

[0031] In one possible implementation of the first aspect, the first device is a packaged chip, and the first region is further provided with a first pad and a first solder ball. The first solder ball is disposed between the packaged chip and the first pad. The packaged chip is electrically connected to the mounting surface in sequence through the first solder ball and the first pad. The shielding film is insulated from the first solder ball and the first pad respectively.

[0032] This implementation method enables electromagnetic shielding and heat dissipation of the packaged chip, and prevents the packaged chip from failing due to electrical connection with the shielding film.

[0033] In one possible implementation of the first aspect, the mounting surface further includes a second region, the first region being located in the middle of the mounting surface and the second region being located at the edge of the mounting surface, the second region being provided with at least one electronic component, and the surface of the electronic component not being provided with a heat dissipation shielding structure.

[0034] In this implementation, the external components in the second area, such as springs, switches, board-to-board connectors, test terminals, and electronic components that need to be debugged, can be directly connected and used with other structures.

[0035] Secondly, embodiments of this application provide a circuit board assembly, which includes a circuit board and a heat dissipation shielding structure. The circuit board has a mounting surface, which includes a first region. The first region is equipped with various electronic components, the heat dissipation shielding structure, and at least one partition. The electronic components include at least an adjacent first device and a second device. The heat dissipation range of the first device is greater than that of the second device. The first device and the second device are separate and spaced apart. The partition is disposed on at least one side of the second device and is not in contact with the second device. The heat dissipation shielding structure includes a shielding film. The shielding film covers at least the top surface of the first device away from the mounting surface, the top surface of the partition away from the mounting surface, and part of the mounting surface. There is a space between the shielding film and the second device. The shielding film is electrically connected to the grounding terminal of the circuit board.

[0036] This application provides a circuit board assembly that supports the shielding film with ribs, forming a cavity between the shielding film and the second device. The second device is cooled by air, and the insulating film can be omitted. It can still achieve good electromagnetic shielding and heat dissipation while making the circuit board assembly thinner and smaller, and simplifying the process of preparing the insulating film.

[0037] In one possible implementation of the second aspect, the mounting surface of the circuit board is further provided with at least one reinforcing structure, the reinforcing structure being located on at least one side of each second device, and the height of the reinforcing structure along the direction perpendicular to the circuit board is less than or equal to the height of the second device along the direction perpendicular to the circuit board.

[0038] In this implementation, the welding strength between the second device and the circuit board can be enhanced by reinforcing the structure.

[0039] In one possible implementation of the second aspect, a rib is provided on the side of the second device away from the first device, and the shielding film covers at least the top surface of the first device, the top surface of the rib, and the side of the rib away from the second device.

[0040] In this implementation, the shielding film is supported by ribs to form a cavity between it and the second device. The second device can dissipate heat through air. At the same time, the shielding film is in contact with the first device, which can achieve good heat dissipation for the first device. In addition, the insulation film is omitted, which can achieve good electromagnetic shielding and heat dissipation effects. The circuit board assembly can be made thinner and smaller, and the process is simplified. This makes the electronic device thinner and smaller, and the performance of the electronic device is better.

[0041] In one possible implementation of the second aspect, a partition rib is provided on each side of the second device, and the shielding film covers at least the top surface of the first device, the top surface of the partition rib, and the side of the partition rib away from the second device.

[0042] This implementation reduces the clearance space between adjacent electronic components and eliminates the need for additional shielding around the second component, thus enabling the circuit board assembly to be made thinner and lighter.

[0043] Thirdly, an electronic device is provided, including a circuit board assembly as described in the first aspect or any possible implementation of the first aspect, and in the second aspect or any possible implementation of the second aspect.

[0044] This application provides an electronic device with good electromagnetic compatibility and heat dissipation, and the electronic device can also be miniaturized and made thinner.

[0045] Fourthly, embodiments of this application provide a method for manufacturing a circuit board assembly, the method comprising:

[0046] A circuit board is provided; wherein the circuit board has a mounting surface, the mounting surface including a first region;

[0047] At least a variety of electronic components are installed in the first area; wherein, the electronic components include at least an adjacent first device and a second device, the heat generation range of the first device is greater than the heat generation range of the second device, the first device and the second device are separate and spaced apart, the space between the first device and the second device includes a first spacer area, and the width-to-depth ratio of the first spacer area is less than or equal to 1:2.

[0048] Release layers are formed on the top surface of the first device on the side away from the mounting surface, at least a portion of the side surface connected to the top surface, the ground terminal of the circuit board, and the first gap area.

[0049] An insulating film is formed by covering the surface of the first device (excluding the bottom surface connected to the mounting surface), the grounding terminal, and a portion of the mounting surface in the first region with insulating material; wherein the insulating film is designed to vary in height according to the electronic component.

[0050] Remove the top surface and at least part of the side surfaces of the first device, the surface of the ground terminal, the insulating film and release layer of the first spacer region;

[0051] A shielding film is formed by covering the top surface and at least part of the sides, grounding terminal, first gap area, and the side of the insulating film away from the circuit board with shielding material; wherein the shape of the shielding film matches the shape of the electronic components and the insulating film, and the shielding film is electrically connected to the grounding terminal;

[0052] Forming a circuit board assembly.

[0053] This application provides a method for manufacturing a circuit board assembly. First, the required structure is formed on the circuit board using SMT technology. Then, a release layer is formed on certain surfaces of some structures. Next, an insulating film that conforms to the shape of each structure is covered. After processing the edge positions corresponding to the insulating film and the release layer, the insulating film at these positions is removed to minimize damage to each structure during the process of removing the insulating film. Then, a conforming shielding film is covered. At this point, the shielding film deposition has no sharp cuts, and the clearance between the shielding film and each structure does not need to be large, thus reducing the risk of electromagnetic wave leakage and effectively improving heat dissipation. In addition, this manufacturing method is simple and easy to implement, which is conducive to industrial production.

[0054] In one possible implementation of the fourth aspect, at least a variety of electronic components are installed in the first region, including:

[0055] At least one rib is also formed in the first region; wherein the rib is disposed on at least one side of the second device and the rib is not in contact with the second device;

[0056] Covering the surface of the first device (excluding the bottom surface connected to the mounting surface), the grounding terminal, and the portion of the mounting surface in the first region with insulating material to form an insulating film includes:

[0057] An insulating film is formed by covering at least the surface of the first device (excluding the bottom surface connected to the mounting surface), the grounding terminal, the portion of the mounting surface in the first region, and the surface of the partition (excluding the bottom surface connected to the mounting surface) with insulating material.

[0058] Removing the top surface and at least part of the side surfaces, the surface of the ground terminal, the insulating film and release layer of the first spacer region of the first device includes:

[0059] Remove the top surface and at least part of the side surface of the first device, the surface of the ground terminal, the insulating film and release layer of the first spacer area, and at least remove the insulating film of the top surface of the partition rib on the side away from the mounting surface;

[0060] Covering the top surface and at least part of the sides, ground terminal, first gap region, and the side of the insulating film away from the circuit board with shielding material to form a shielding film includes:

[0061] The shielding material covers at least the top surface and at least part of the sides of the first device, the grounding terminal, the first gap area, the side of the insulating film away from the circuit board, and part of the top surface of the partition rib to form a shielding film.

[0062] In this implementation method, setting up ribs can provide good electromagnetic shielding for two adjacent electronic components, and it is simple and easy to implement.

[0063] In one possible implementation of the fourth aspect, removing the top surface and at least part of the side surfaces of the first device, the surface of the ground terminal, the insulating film of the first spacer region, and the release layer includes:

[0064] The top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the edge of the insulating film and release layer of the first interval area are laser-etched around the perimeter using a laser engraving process, and then the top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the insulating film and release layer of the first interval area are peeled off.

[0065] In this implementation, the laser engraving process only removes the edges of the insulating film and release layer, which can shorten the laser engraving time and prevent the laser engraving temperature from becoming too high, thus protecting the performance of electronic components.

[0066] In one possible implementation of the fourth aspect, the mounting surface further includes a second region, the first region being located at the middle of the mounting surface and the second region being located at the edge of the mounting surface, and the second region having at least one second device mounted thereon.

[0067] A release layer is formed on the top surface of the first device away from the mounting surface, at least a portion of the side surface connected to the top surface, the ground terminal of the circuit board, and the first gap area, including:

[0068] A release layer is formed on the top surface and at least part of the sides, ground terminal, and first gap area of ​​the first device in at least the first region, and a protective cover is formed around the second device in the second region;

[0069] The circuit board assembly includes:

[0070] Remove the protective cover to form the circuit board assembly.

[0071] In this implementation, the required structure is first formed on the circuit board using SMT technology. Then, a protective cover is used to protect the electronic components in the second area, which does not require a heat dissipation shielding structure, so that the electronic components in the second area are not affected by the heat dissipation shielding structure formation process. At the same time, the clearance space is reduced. Furthermore, the laser engraving process for removing the insulating film and release film is simple, takes less time, and does not generate high temperatures that affect the performance of the electronic components.

[0072] In one possible implementation of the fourth aspect, after removing the top surface and at least part of the side surfaces of the first device, the surface of the ground terminal, the insulating film and release layer of the first spacing region, and before covering the top surface and at least part of the side surfaces of the first device, the ground terminal, the first spacing region and the side of the insulating film away from the circuit board with shielding material to form a shielding film, the preparation method further includes:

[0073] At least a primer coating is formed on the top surface of the first device;

[0074] Covering the top surface and at least part of the sides, ground terminal, first gap region, and the side of the insulating film away from the circuit board with shielding material to form a shielding film includes:

[0075] The shielding material is applied to the surfaces of the primer coating (excluding the surface in contact with the first device), the grounding terminal, the first gap area, and the surface of the insulating film away from the circuit board to form a shielding film.

[0076] In this implementation, a base coating is formed on the top surface of the high-heat-generating device without an insulating film. The heat dissipation of the high-heat-generating device can be improved and the adhesion of the shielding film can be enhanced by the buffering, oxidation resistance, breakdown resistance and corrosion resistance properties of the base coating.

[0077] This application provides a circuit board assembly and its manufacturing method, as well as an electronic device. The heat dissipation shielding structure in the circuit board assembly can provide good electromagnetic shielding and heat dissipation for various electronic components, grounding terminals, and the spacing between adjacent electronic components on the circuit board, thereby extending the service life of electronic components and improving the working stability of the circuit board assembly. When applied to electronic devices, the electronic devices have good electromagnetic compatibility and heat dissipation, and can achieve miniaturization and thinning, resulting in better performance. Attached Figure Description

[0078] Figure 1 A schematic diagram of the structure of an electronic device with a shielding cover, provided for related technologies;

[0079] Figure 2 A schematic diagram of another electronic device with a shielding cover provided for related technologies;

[0080] Figure 3 This is a schematic diagram of the overall structure of an electronic device provided in an embodiment of this application;

[0081] Figure 4 for Figure 3 A schematic diagram of the disassembled structure of electronic devices in China;

[0082] Figure 5 This is a schematic diagram of the structure of a first type of electronic device provided in an embodiment of this application;

[0083] Figure 6 This is a schematic diagram of the structure of a second electronic device provided in an embodiment of this application;

[0084] Figure 7 This is a schematic diagram of the structure of a third electronic device provided in an embodiment of this application;

[0085] Figure 8 This is a schematic diagram of the structure of the fourth electronic device provided in the embodiments of this application;

[0086] Figure 9 This is a schematic diagram of the structure of the fifth electronic device provided in the embodiments of this application;

[0087] Figure 10 This is a schematic diagram of the structure of the sixth electronic device provided in the embodiments of this application;

[0088] Figure 11 This is a schematic diagram of the structure of the seventh electronic device provided in the embodiments of this application;

[0089] Figure 12 This is a schematic diagram of the structure of the eighth electronic device provided in the embodiments of this application;

[0090] Figure 13 This is a schematic diagram of the structure of the ninth electronic device provided in the embodiments of this application;

[0091] Figure 14 This is a schematic diagram of the structure of the tenth electronic device provided in the embodiments of this application;

[0092] Figure 15 A schematic diagram of the structure of the eleventh electronic device provided in the embodiments of this application;

[0093] Figure 16 This is a schematic diagram of the structure of the twelfth type of electronic device provided in the embodiments of this application;

[0094] Figure 17 This is a schematic diagram of the structure of the thirteenth electronic device provided in the embodiments of this application;

[0095] Figure 18 This is a schematic diagram of the structure of the fourteenth electronic device provided in the embodiments of this application;

[0096] Figure 19 A process flow diagram for fabrication of a circuit board assembly is provided in an embodiment of this application;

[0097] Figure 20 A process flow diagram for the fabrication of another circuit board assembly provided in this application embodiment;

[0098] Figure 21 This is a process flow diagram for the fabrication of another circuit board assembly provided in an embodiment of this application. Detailed Implementation

[0099] The technical solutions in the embodiments of this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B; the word "and / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone.

[0100] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more. "At least one" means one or more.

[0101] First, some terms used in the embodiments of this application will be explained in detail to facilitate understanding by those skilled in the art.

[0102] 1. EMI

[0103] EMI refers to the phenomenon of interference caused by the interaction of electromagnetic waves with electronic components.

[0104] When electronic devices are operating, they should not be interfered with by external electromagnetic waves, nor should they radiate electromagnetic waves that interfere with the outside world. This requires electromagnetic shielding to block the propagation of electromagnetic waves. EMI includes electrostatic discharge (ESD), radio frequency interference (RFI), and any other type of electromagnetic radiation or influence.

[0105] 2. Physical vapor deposition (PVD)

[0106] PVD refers to the process of vaporizing the surface of a material source (solid or liquid) into gaseous atoms or molecules, or partially ionizing them into ions, under vacuum conditions using physical methods, and then depositing a thin film on the substrate surface through a low-pressure gas or plasma process.

[0107] 3. Chemical vapor deposition (CVD)

[0108] CVD refers to the process of introducing vapors of gaseous or liquid reactants containing elements constituting the thin film, along with other gases required for the reaction, into a reaction chamber to conduct a chemical reaction on the substrate surface, thereby generating a thin film and depositing it on the substrate surface.

[0109] 4. Chemical plating

[0110] Chemical immersion plating refers to a process in which metal ions are reduced to metals in a solution (also called plating bath) without the need for electricity or external current, and deposited on the surface of the substrate to form a dense coating, based on the principle of redox reaction.

[0111] 5. System-on-a-Chip (SOC)

[0112] SOC refers to a dedicated integrated circuit that contains a complete system and all embedded software.

[0113] 6. Double Data Rate (DDR) chip

[0114] DDR refers to memory that can transmit data twice within one clock cycle, that is, it can transmit data once during the rising phase and once during the falling phase of the clock.

[0115] 7. Printed circuit board (PCB)

[0116] A PCB is a support structure for electronic components and a provider of circuit connections for electronic components. It is manufactured using electronic printing technology.

[0117] 8. Surface Mount Technology (SMT)

[0118] SMT refers to surface-mount technology that mounts leadless or short-lead surface-mount electronic components onto the surface of a PCB or other substrate and then solders them using methods such as reflow soldering or dip soldering.

[0119] 9. Printed circuit board assembly (PCBA)

[0120] PCBA refers to the finished product of a PCB after it has undergone SMT or dual in-line package (DIP) insertion processing.

[0121] 10. Thermal interface materials (TIM)

[0122] TIM refers to materials that can reduce the thermal resistance of heat transfer when two materials are joined or in contact, thereby improving heat dissipation performance.

[0123] 11. Board-to-board (BTB) connector

[0124] BTB refers to a component used to connect different structures in electronic devices. It can provide a reliable electrical connection, allowing the transmission of signals, power, and data between one structure and another.

[0125] 12. Skin Depth

[0126] Skin depth is an important parameter describing the attenuation of electromagnetic waves in a conductor.

[0127] The above is a brief introduction to the terms involved in the embodiments of this application, and will not be repeated below.

[0128] Circuit boards, as a major component of electronic devices, serve functions such as circuit connection, signal transmission, power supply, control, and drive. The ability of circuit boards to perform these functions relies primarily on the various electronic components mounted on them. As the functions of electronic devices become increasingly sophisticated, the types and number of electronic components on circuit boards also gradually increase.

[0129] During operation, some electronic components on a circuit board generate and emit electromagnetic waves of various frequencies and intensities. These electromagnetic waves may cause interference between electronic components, resulting in electromagnetic interference (EMI), which can affect the normal function of the electronic components. Furthermore, EMI may also affect external electronic equipment and users. Simultaneously, most electronic components generate heat during operation. As usage time increases, the amount of heat generated by these components also increases. If this heat cannot be dissipated in time, the electronic components will experience problems such as overheating and accelerated aging, affecting their performance and, in severe cases, damaging them and shortening their lifespan.

[0130] Therefore, strict electromagnetic compatibility control and heat dissipation control are required for electronic equipment.

[0131] To achieve EMI shielding, a shielding structure can be set around the protected target on the circuit board to provide EMI shielding. Commonly used shielding structures include, but are not limited to, shielding covers. By placing the shielding cover over the protected target, such as electronic components, circuits, assemblies, and the entire circuit board, the shielding cover can block and isolate the electronic components and signals on the circuit board, thereby preventing the electronic components from being interfered with by external electromagnetic waves, or preventing the electromagnetic waves generated by the electronic components inside the shielding cover from affecting other devices.

[0132] For example, Figure 1 An electronic device 01 to which embodiments of this application are applicable is shown.

[0133] like Figure 1 As shown, electronic device 01 may include circuit board 1, electronic components 2, shielding cover 5, and middle frame 8.

[0134] The circuit board 1 may have a mounting surface 11 on which electronic components 2 are mounted and electrically connected. A shielding cover 5 is disposed around the electronic components 2 and electrically connected to the grounding terminal of the circuit board 1, or electrically connected to the grounding terminal of the electronic device 01. The shielding cover 5, based on the principles of electromagnetic wave reflection and absorption, is used to shield the electronic components 2 from electromagnetic waves, thus improving the anti-interference capability, signal integrity, and stability of the circuit board 1.

[0135] In addition, the middle frame 8 is located on the side of the shield 5 away from the circuit board 1, and the middle frame 8 can be used to support some structures in the electronic device 01.

[0136] Some electronic components exhibit high radiation, some high heat generation, and some combine both. Therefore, to improve heat dissipation within a shielded enclosure, reducing the enclosure's height could be considered, allowing at least some components to directly contact the enclosure.

[0137] Please refer to this again. Figure 1 The shielding cover 5 consists of a shielding frame 6 and a shielding cover 7. The electronic components 2 include a first component 3 and a second component 4. The following explanation uses an example where the first component 3 is a System-on-a-Chip (SOC) and the second component 4 is a DDR. Of course, the electronic components 2 include, but are not limited to, the first component 3 and the second component 4; the specific application will vary.

[0138] like Figure 1 As shown, the SOC is mounted on the mounting surface 11 of the circuit board 1, and the DDR is mounted on the side of the SOC away from the circuit board 1. A shielding frame 6 is disposed around the SOC and DDR, without contacting either the SOC or the DDR. One end of the shielding frame 6 is electrically connected to the mounting surface 11. A shielding cover 7 is disposed along the shielding frame 6 in a first direction (…). Figure 1 On the side away from SOC and DDR (in the ox direction), the shielding cover 7 partially contacts the shielding frame 6, and the shielding cover 7 is also disposed along the shielding frame 6 in the second direction ( Figure 1 The shielding cover 7 is located on the side away from the DDR (in the oz direction), and a portion of the shielding cover 7 contacts the DDR. The middle frame 8 is located on the side of the shielding cover 7 away from the circuit board 1.

[0139] It should be noted that, Figure 1The ox direction is parallel to circuit board 1, and the oz direction is perpendicular to the ox direction.

[0140] Since the shielding cover 5 has better thermal conductivity than air, the electronic components 2 can dissipate heat directly through the shielding cover 5, thus improving heat dissipation performance.

[0141] However, to achieve a shielding effect, the shielding cover 7 is usually quite thick along the oy direction, typically requiring a thickness of about 100μm-150μm. Furthermore, when the shielding cover 7 is fastened to the shielding frame 6, sufficient fastening width needs to be left at the edges of both to ensure the shielding cover 7 can be securely fastened to the shielding frame 6, minimizing electromagnetic wave leakage. All of these factors contribute to the relatively thick thickness of the shielding cover 5 formed by the shielding cover 7 and the shielding frame 6 along the oy direction.

[0142] and, Figure 1 The SOC is located on one side of the circuit board 1, and the DDR is stacked on the side of the SOC away from the circuit board 1. The DDR is partially connected to the shielding cover 7. Since the stacking height of the SOC and DDR is usually relatively high, the height of the shielding cover 5 along the oy direction also needs to be relatively high, which makes it difficult for the electronic device 01 to achieve a thinner and smaller design.

[0143] For example, Figure 2 Another electronic device 01 to which this application embodiment applies is shown.

[0144] To alleviate Figure 1 The weight, thickness, and height of the middle shield 5 are adjusted to further improve heat dissipation, such as... Figure 2 As shown, copper (Cu) foil 10 is used instead of... Figure 1 The thickness of the copper foil 10 along the oy direction in the shielding cover 7 is smaller than that of the shielding cover 7 along the oy direction. An opening is provided in the shielding frame 6 at the position corresponding to the higher DDR, and the copper foil 10 covers this opening, allowing the opening to be sealed with the copper foil 10 to ensure shielding effectiveness. Simultaneously, to connect the copper foil 10 to the shielding frame 6, a copper foil adhesive film 9 is provided between the copper foil 10 and the shielding frame 6, bonding the copper foil 10 to at least the surface of the shielding frame 6 away from the circuit board 1 through the copper foil adhesive film 9. Furthermore, the middle frame 8 is located on the side of the copper foil 10 away from the circuit board 1.

[0145] It should be noted that the copper foil adhesive film 9 can be a thermally conductive adhesive, etc., to transfer the heat of the electronic components 2 to the copper foil 10, thereby improving the thermal conductivity.

[0146] However, to achieve the shielding effect, the thickness of the copper foil 10 along the oy direction cannot be too thin, generally needing to reach approximately 20μm-45μm. Simultaneously, since the stacking height of SOCs and DDRs is typically high, the height of the shielding cover 5 along the oy direction also needs to be relatively high, resulting in less effective weight reduction and thinning of the shielding cover 5. Furthermore, the copper foil 10 itself cannot perfectly conform to the 3D surface, preventing the shielding cover 5 from fully conforming to the electronic component 2, leading to… Figure 2 The shielding cover 5 is limited in many application scenarios.

[0147] Please refer to this again. Figure 1 and Figure 2 The electronic components 2 on circuit board 1 are usually of varying heights, and this problem also exists for the electronic components 2 inside the shielding cover 5. The side of the shielding cover 5 opposite to the surface of circuit board 1 is parallel to the mounting surface 11 of circuit board 1, which makes the height of the shielding cover 5 constant, resulting in only the tallest electronic component 2 (…) being able to fit within it. Figure 1 and Figure 2 The DDR in the middle can directly contact the shielding cover 5, while the shorter electronic components 2 inside the shielding cover 5 can... Figure 1 and Figure 2 The SOC in the shield is still surrounded by air inside the shield 5, which does not provide good heat dissipation for the shorter electronic components 2.

[0148] In view of this, this application provides a circuit board assembly in which the heat dissipation shielding structure can effectively provide electromagnetic shielding and heat dissipation for various electronic components, grounding terminals and the spacing between adjacent electronic components on the circuit board, thereby extending the service life of electronic components and improving the working stability of the circuit board assembly.

[0149] This application does not limit the specific type of electronic device. In some embodiments, the electronic device may include mobile phone, tablet, notebook, wearable device (e.g., smart bracelet, smartwatch, and headphones), laptop, handheld computer, ultra-mobile personal computer (UMPC), cellular phone, personal digital assistant (PDA), augmented reality (AR) / virtual reality (VR) device and other Internet of Things (IoT) devices, in-vehicle electronic device, and may also be a television, large screen, printer, projector, etc.

[0150] This application does not limit the specific form of the above-mentioned electronic device. For ease of explanation, the following embodiments all use a mobile phone as an example for illustration.

[0151] Please refer to Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of the electronic device 01 to which some embodiments of this application are applicable. Figure 4 for Figure 3 The diagram shows a disassembled view of electronic device 01. Wherein, Figure 3 and Figure 4 The electronic device 01 shown is illustrated using a tablet phone as an example. In other embodiments, the electronic device may be other types of mobile phones, such as foldable phones.

[0152] exist Figure 3 and Figure 4 In the example, electronic device 01 may include a display screen 100, a mid-frame 101, a back cover 102, a circuit board assembly 103, and a battery 104, etc. It is understood that... Figure 3 and Figure 4 The accompanying drawings below only schematically show some components of electronic device 01. The actual shape, size, position, and structure of these components are not subject to change. Figure 3 and Figure 4 And the limitations of the figures below.

[0153] The specific structure of the electronic device to which the embodiments of this application apply will be further described below.

[0154] Please refer to this again. Figure 3 and Figure 4 The display screen 100 in the phone is located on one side of the mid-frame 101.

[0155] The display screen 100 can be used to display image information, etc. The display screen 100 can be any one of the following: liquid crystal display (LCD), organic light emitting diode (OLED) display, mini light emitting diode (Mini LED) display, micro light emitting diode (Micro LED) display, etc.

[0156] The back cover 102 of the mobile phone can be located on the side of the middle frame 101 away from the display screen 100. The back cover 102 and the middle frame 101 can form an internal storage space for the mobile phone, which can accommodate structures such as the circuit board assembly 103 and the battery 104.

[0157] Battery 104 can be used to provide power to components inside the mobile phone, such as display screen 100 and circuit board assembly 103.

[0158] The circuit board assembly 103 may include a circuit board 1 and electronic components 2, and its type may be PCBA, etc.

[0159] In the application, circuit board 1 can be used to carry electronic components 2 and to complete signal interaction with electronic components 2. Figure 4 The illustration is based on an example of a circuit board assembly 103 having two electronic components 2. Of course, the number of electronic components 2 is not limited to two; the specific number depends on the actual application.

[0160] Circuit board 1 can be a rigid circuit board, such as a PCB, a flexible printed circuit board (FPC), or a rigid-flex PCB. Circuit board 1 can use an FR-4 dielectric board, a Rogers dielectric board, or a hybrid dielectric board of FR-4 and Rogers, etc. It should be noted that FR-4 is a designation for a flame-retardant material grade, and the Rogers dielectric board is a high-frequency board.

[0161] Furthermore, circuit board 1 can be a single-sided board or a double-sided board. A single-sided board means that electronic components 2 are arranged on one side of circuit board 1, while a double-sided board means that electronic components 2 are arranged on both sides of circuit board 1. Circuit board 1 can be a radio frequency (RF) board or an application processor (AP) board. The RF board can be used to carry radio frequency integrated circuits (RF ICs), radio frequency power amplifiers (RF PAs), etc., while the application processor board can be used to carry SOCs, DDRs, main power management units (PMUs), auxiliary power management chips, etc.

[0162] In applications, electronic components 2 may include active components and passive components.

[0163] Active devices are devices that can actively input and output electrical energy or signals. They can amplify, control, and regulate current and voltage through specific semiconductor materials and design structures. Active devices can include NOR flash memory, System-on-a-Chip (SoC), codec IC, charger IC, Bluetooth chip, radio frequency chip, wireless fidelity (WiFi) chip, near field communication (NFC) chip, power system monitoring and management unit (PMU), central processing unit (CPU), graphics processing unit (GPU), and battery 104, etc. These active devices typically perform high-load computing, erasing and writing, energy conversion, communication, and display functions, and are therefore high-heat-generating devices.

[0164] Taking a System-on-a-Chip (SoC) as an example, the active device on circuit board 1 can include a processor and a memory. The memory is located on one side of the processor, which is connected to circuit board 1. The processor, as the main computing engine, can execute instructions and handle various tasks. The memory is electrically connected to the processor to store program code, data, and temporary variables. The memory can include random access memory (RAM) and read-only memory (ROM). Furthermore, the active device can also include external interfaces, such as universal serial bus (USB), Ethernet, and wireless communication (including but not limited to Bluetooth and WiFi).

[0165] Optionally, active devices may also include controllers, input / output interfaces, power management and other functional modules, which can be adjusted according to the actual functions of the active devices, and no specific limitations are made here.

[0166] Passive devices are electronic components that cannot actively input or output electrical energy or signals. Passive devices can include resistors, capacitors, sensors, diodes, photosensitive devices, and transistors, etc.

[0167] During the operation of circuit board assembly 103, active devices typically perform calculations, control, and energy conversion, resulting in higher power consumption. This leads to active devices generating more heat than passive devices. It can be seen that the heat generated by circuit board assembly 103 during operation primarily originates from the active devices. Therefore, when cooling circuit board assembly 103, the focus should first be on improving the heat dissipation effect on the active devices.

[0168] It should be noted that a circuit board 1 can be equipped with multiple active devices and multiple passive devices. The specific types and quantities of active and passive devices can be adjusted according to the actual function of the circuit board 1, and no specific limitations are made here.

[0169] Of course, the phone may also include other components such as a microphone, speaker, and camera. Only the aspects relevant to the invention are described here; the rest will not be discussed in detail.

[0170] Based on the above structure, the circuit board assembly provided in this application is applied to electronic devices, which effectively alleviates the electromagnetic compatibility problem of electronic devices, has good heat dissipation performance, and enables electronic devices to be miniaturized and made thinner, with better performance.

[0171] Please refer to the following: Figures 5 to 21 This application provides a detailed description of the heat dissipation shielding structure 02, the circuit board assembly and its preparation method, and the electronic device 01 provided in the embodiments of this application.

[0172] Example 1:

[0173] Figures 5 to 9 An electronic device 01 to which embodiments of this application are applicable is shown.

[0174] like Figure 5 and Figure 6 As shown, the circuit board assembly provided in this application embodiment includes a circuit board 1. The circuit board 1 has a mounting surface 11, which includes at least a first region z1. Various electronic components are mounted on the first region z1. The first region z1 also has at least one ground terminal D1. There is at least a first gap region G1 between two adjacent electronic components. The width-to-depth ratio of the first gap region G1 is less than or equal to 1:2. The electronic components include at least a first device 3 and a second device 4. The heat generation range of the first device 3 is greater than that of the second device 4.

[0175] In applications, mounting surface 11 can be used to mount various structures using SMT technology, and these structures can be used to realize the functions of circuit board 1.

[0176] The method of mounting the above structures on the mounting surface 11 is not specifically limited. For example, the structures can be mounted using at least one of the following: solder pads, solder balls, and solder pillars. Specifically, such as... Figure 5 and Figure 6As shown, nine first pads 16 and nine first solder balls 17 can be placed on the mounting surface 11 at the position corresponding to a first device 3. Each first solder ball 17 is located between each first pad 16 and the first device 3. Two second pads 15 are placed on the mounting surface 11 at the position corresponding to a second device 4. Then, the first pads 16, second pads 15 and first solder balls 17 are heated and melted. After cooling, the first pads 16 and first solder balls 17 form an electrical connection structure between the first device 3 and the mounting surface 11, and the second pads 15 form an electrical connection structure between the second device 4 and the mounting surface 11. These electrical connection structures can realize the fixation and electrical connection of the first device 3 and the second device 4 to the circuit board 1.

[0177] also, Figure 6 and Figure 5 The difference is: Figure 6 It also has a third device 14, which is electrically connected to the mounting surface 11 via four second solder balls 21 and four third solder pads 20.

[0178] In other embodiments, electronic components may also be inserted into the mounting surface 11, without specific limitations.

[0179] Figure 5 The illustration is given using an electronic component comprising one first component 3 and four second components 4 as an example. Figure 5 As shown, the first device 3 can be a high-heat-generating device, such as an active device, and the second device 4 can be a low-heat-generating device, such as a passive device. The heat generation range of the high-heat-generating device is much larger than that of the low-heat-generating device. For example, Figure 5 The first device 3 in the text can be a first packaged chip, for example, a first packaged chip encapsulated using molding compound. Figure 5 The second device 4 in the diagram can be a capacitor.

[0180] Figure 6 The illustration is given using an electronic component consisting of a first component 3, two second components 4, and a third component 14. Figure 6 The first device 3 and the second device 4 in the text can be referenced. Figure 5 This will not be elaborated upon here. Figure 6 The third device 14 can also be a high-heat-generating device. The heat generation range of the third device 14 is equal to that of the first device 3, but the heat generation of the third device 14 is less than that of the first device 3. For example, Figure 6 The third device 14 can be a second packaged chip, for example, a second packaged chip encapsulated using molding compound.

[0181] In application, Figure 5 and Figure 6The number of the first device 3, the second device 4 and the third device 14 can be one or more. The structure, volume and type of the first device 3, the second device 4 and the third device 14 can be obtained by referring to relevant technologies, and will not be elaborated here.

[0182] It should be understood that "mounting surface 11 includes at least the first region z1" means that: mounting surface 11 may only include the first region z1, and all structures are located in the first region z1; or, mounting surface 11 may include other regions besides the first region z1, such as a second region. In this case, the first region z1 may be located at the center of mounting surface 11, while the second region may be located at the edge of mounting surface 11. The second region may be connected to or not connected to the first region z1. Therefore, the second region may also have some structures installed. For example, the second region may have external components such as spring contacts, switches, BTB terminals, test terminals, and electronic components requiring debugging (e.g., capacitors). These external components need to be exposed for subsequent connection to other structures or for testing purposes, and therefore cannot be covered by other structures; that is, the second region will not have a heat dissipation shielding structure.

[0183] Please refer to this again. Figure 5 and Figure 6 The electronic device 01 also includes a heat dissipation shielding structure 02, which is disposed in the first region z1 of the mounting surface 11. The heat dissipation shielding structure 02 includes an insulating film 18 and a shielding film 19. The insulating film 18 covers the position except for the top surface of the first device 3 away from the mounting surface 11 and all the sides connected to the top surface, the top surface of the third device 14 away from the mounting surface 11 and all the sides connected to the top surface, the grounding terminal D1, and the first interval G1. The insulating film 18 is used to undulate with the different heights of the first device 3, the second device 4, and the third device 14. The shielding film 19 covers the outer surface of the insulating film 18, the top surface of the first device 3, all the sides of the first device 3, the top surface of the third device 14, all the sides of the third device 14, the grounding terminal D1, and the first interval G1. The shape of the shielding film 19 matches the shape of the insulating film 18, and the shielding film 19 is electrically connected to the grounding terminal D1.

[0184] It should be noted that, in Figure 5 and Figure 6 In the above, no heat dissipation shielding structure 02 is provided between adjacent first pads 16, adjacent second pads 15, adjacent first solder balls 17, adjacent third pads 20, and adjacent second solder balls 21.

[0185] In this embodiment, the insulating film 18 does not cover the grounding terminal D1, thereby allowing the shielding film 19 to be electrically connected to the grounding terminal D1, thus achieving grounding of the heat dissipation shielding structure 02. For example, as shown... Figure 5 and Figure 6 As shown, the grounding terminal D1 can be located between the first interval region G1 and the insulating film 18 on the side of the second device 4 away from the first device 3. Alternatively, it can be located in the second region, depending on the actual application. Since the heat dissipation shielding structure 02 generates current, creating a potential difference at different locations, and the impedance of the ground signal is low, by grounding the heat dissipation shielding structure 02, the current on the shielding film 19 can be directly conducted away through the grounding terminal D1, ensuring that electromagnetic interference does not leak out of the heat dissipation shielding structure 02.

[0186] There are no specific limitations on the grounding terminal D1. For example, the grounding terminal D1 can be a grounding pad, ground network (GND), etc.

[0187] The electrical connection method between the shielding film 19 and the grounding terminal D1 is not specifically limited. For example, the connection can be achieved by bonding, welding, or thermoforming. For example, the shielding film 19 can be welded to the grounding pad, which can improve the connection stability and reliability between the shielding film 19 and the grounding pad. At the same time, since no additional grounding structure is set, it is convenient to simplify the circuit board 1 and the heat dissipation shielding structure 02, and also facilitates the miniaturization of the circuit board assembly.

[0188] To facilitate the explanation of the positions of each structure in the heat dissipation shielding structure 02, the embodiments of this application establish a coordinate system based on the circuit board 1. For example... Figure 5 and Figure 6 As shown, the thickness direction of the circuit board 1 (i.e. the height direction of the electronic components) is set as the oz direction, which is also the stacking direction of the insulating film 18 and the shielding film 19. The length direction of the circuit board 1 is set as the ox direction, and the oz direction is perpendicular to the ox direction.

[0189] Therefore, the first device 3, the second device 4, and the third device 14 each have a side surface, a top surface, and a bottom surface. Let the side of the first device 3 facing and connected to the mounting surface 11 be the bottom surface. Then, along the oz-axis, the side opposite the bottom surface is the top surface, and the surface between the bottom and top surfaces is the side surface. For example, if the first device 3 is a cuboid structure, there is one top surface and one bottom surface, and the side surface is the four sides between the top and bottom surfaces; or, if the first device 3 is a cylindrical structure, there is one top surface and one bottom surface, and the side surface is a curved surface between the top and bottom surfaces. It should be noted that other electronic components can refer to the first device 3, and will not be elaborated further here.

[0190] Understandably, this is done to facilitate the explanation of the internal structure of circuit board 1 and heat dissipation shielding structure 02. Figure 5 and Figure 6 The structure provided is a schematic diagram of the circuit board 1 and the heat dissipation shielding structure 02 after being cut by a plane parallel to the xz plane.

[0191] In this embodiment, taking a plastic-encapsulated chip with a cuboid structure as an example, the insulating film 18 can cover zero, one, two, three, four, or five sides of the plastic-encapsulated chip, and the shielding film 19 can cover the top surface and five sides of the plastic-encapsulated chip. In addition, the insulating film 18 can also be disposed between the bottom surface of the first device 3 and the mounting surface 11 along the oz direction, and located between the structure composed of the second device 4, the first solder ball 17, and the first solder pad 16 along the ox direction. The insulating film 18 is in contact with the bottom surface of the first device 3 and the circuit board 1, respectively, and is not in contact with the first solder ball 17 and the first solder pad 16, respectively. Thus, the insulating film 18 can be used to isolate the first device 3 from the shielding film 19 to avoid short-circuit faults in the first device 3.

[0192] Of course, instead of providing an insulating film 18 between the bottom surface of the first device 3 and the mounting surface 11 along the oz direction and between the second device 4 and the structure composed of the first solder ball 17 and the first solder pad 16 along the ox direction, the exposed parts of the first solder pad 16 and the first solder ball 17 can be insulated from the shielding film 19. For example, the exposed surfaces of the first solder pad 16 and the first solder ball 17 can be covered with an insulating structure, so that the shielding film 19 will not contact the first solder pad 16 and the first solder ball 17 to achieve insulation isolation.

[0193] It should be noted that the isolation settings for the third device 14 can be referenced from those for the first device 3, which will not be elaborated here.

[0194] To ensure the heat dissipation shielding structure 02 can adhere to the surface of the electronic components, the insulating film 18 of the heat dissipation shielding structure 02 should be a flexible structure. Therefore, the insulating film 18 needs to vary in height according to the different electronic components. Specifically, the insulating film 18 can vary in height according to the second device 4 on the mounting surface 11, so that the insulating film 18 can cover the second device 4 in a conformal manner. At the same time, it can also avoid the insulating film 18 being too thick on the surface of the shorter second device 4, thus saving local oz-axis space, isolating the second device 4 from the shielding film 19, acting as a buffer when the second device 4 is impacted, and also improving the heat dissipation effect of the second device 4. With this setting, the gap between the insulating film 18 and the electronic components is small, and ideally it can completely adhere to the surface of the electronic components, thereby reducing the overall thickness of the circuit board 1 and thus achieving the thinning of the circuit board assembly.

[0195] The thickness of the insulating film 18 is not specifically limited. For example, the thickness of the insulating film 18 along the oz direction can be greater than or equal to 10 μm to cover and isolate electronic components, thereby avoiding short circuits.

[0196] The material of the insulating film 18 is not specifically limited. To facilitate heat dissipation from electronic components and considering the potential stretching of the film during the manufacturing process, the insulating film 18 can be made of a material with a thermal conductivity greater than air, such as silicone rubber or resin adhesive. The resin in the resin adhesive can include polyimide (PI), epoxy resin (EP), polyethylene naphthalate (PEN), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), and polyurethane (PU), etc. Therefore, the insulating film 18 can be used to improve the efficiency of heat dissipation from electronic components.

[0197] The thermal conductivity of the insulating film 18 is not specifically limited; for example, it can be 0.2 W / m·K to 10 W / m·K. Since the thermal conductivity of air is approximately 0.024 W / m·K, which is much lower than that of the insulating film 18, by placing the insulating film 18 between the shielding film 19 and the electronic components, and by having the insulating film 18 conformally cover individual electronic components, not only can isolation between different electronic components and the shielding film be achieved, but the insulating film 18 can also conduct heat to the electronic components it covers, improving the thermal conductivity between these electronic components and the shielding film 19.

[0198] Furthermore, by way of example, the surface resistance (1000V) of the insulating film 18 can be greater than or equal to 4kΩ; the Young's modulus (23°C) of the insulating film 18 can be greater than or equal to 10MPa; the elongation at break of the insulating film 18 can be greater than or equal to 100%; and the tensile strength of the insulating film 18 can be greater than or equal to 10MPa.

[0199] In addition, in this embodiment, in order for the heat dissipation shielding structure 02 to adhere to the surface of the electronic components, the shielding film 19 in the heat dissipation shielding structure 02 should also be a flexible structure. Specifically, the shielding film 19 covers the outer surface of the insulating film 18, and the shape of the shielding film 19 matches the shape of the insulating film 18 and the electronic components it covers. The shielding film 19 is also electrically connected to the ground terminal D1 and the first gap area G1 of the circuit board 1. Thus, the undulation trend of the shielding film 19 can match the undulation trend of the insulating film 18 and the electronic components it covers, and it adheres well to the surface of the insulating film 18 and the electronic components. This can save space in the oz direction locally, and can also shorten the path for electronic components of different heights to transfer heat to the shielding film 19, which facilitates heat dissipation for electronic components of different heights.

[0200] Since the shielding film 19 is conductive, it can provide good electromagnetic shielding. At the same time, the thermal conductivity of the shielding film 19 is usually greater than that of the insulating film 18. For example, the thermal conductivity of the shielding film 19 can be 2W / m·K to 380W / m·K, which is very good. Therefore, by placing the shielding film 19 in direct contact with the high-heat-generating device, the efficiency of the high-heat-generating device in transferring heat to the shielding film 19 can be improved, and the heat of the high-heat-generating device can be better transferred out through the shielding film 19, thereby improving the heat dissipation effect.

[0201] The material and thickness of the shielding film 19 are not specifically limited. The material of the shielding film 19 can be a mixture of metal, resin and metal particles, etc.

[0202] When the shielding film 19 is a metal film, the metal can be a single metal, such as copper, nickel, chromium, aluminum, silver, iron, and gold, or an alloy or composite. For example, the shielding film 19 is a copper film. Copper film is a conventional material in the art, readily available, and has a thermal conductivity of approximately 380 W / m·K, exhibiting good electrical conductivity and weldability, which facilitates a stable connection with the grounding terminal D1. Furthermore, the copper film possesses good flexibility, which is beneficial for the adhesion of the shielding film 19 to its covering structure.

[0203] The thickness of the metal thin film can range from 0.5 μm to 25 μm, which is relatively thin. When using a metal thin film as a shielding film 19, according to the skin depth formula and by obtaining metal thin films with different conductivity at different frequencies, a metal thin film of 0.5 μm to 5 μm can meet the requirements for good shielding and thermal conductivity.

[0204] When the shielding film 19 is a conductive paste composed of a mixture of resin and metal particles, the conductive paste can be silver paste, carbon paste, copper paste, gold paste, conductive adhesive, alloy thermally conductive paste, graphene thermally conductive paste, etc. For example, the shielding film 19 is a conductive silver paste film with a thermal conductivity of approximately 2.5 W / m·K and a thickness of 40 μm to 60 μm. To ensure good tensile strength of the conductive silver paste film, the filling ratio of metal particles in the conductive silver paste cannot be too high. Furthermore, to ensure good shielding and heat dissipation effects, the thickness of the conductive silver paste film needs to be slightly greater than the thickness of the metal film.

[0205] Understandably, the material of the shielding film 19 can be selected according to actual needs. The material of the shielding film 19 can be at the micron or nanometer level, and no specific limitation is made here.

[0206] Furthermore, when the material of the shielding film 19 is metal, for example, the resistivity of the shielding film 19 can be greater than or equal to 10. -4 Ω·m.

[0207] When the material of the shielding film 19 is a conductive paste, for example, the resistivity of the shielding film 19 can be greater than or equal to 10. -4 Ω·m; the Young's modulus of the shielding film 19 can be greater than or equal to 80 MPa; the elongation at break of the shielding film 19 can be greater than or equal to 30%; the tensile strength of the shielding film 19 can be greater than or equal to 10 MPa.

[0208] It should be noted that the electronic device 01 in this application embodiment is applicable to all frequency bands. At the same time, the thickness of the shielding film 19 needs to be adjusted according to different frequencies. For example, the higher the frequency, the thinner the shielding film 19.

[0209] In this embodiment, the first gap region G1 refers to the position between any two adjacent electronic components where the width-to-depth ratio is less than or equal to 1:2. This first gap region G1 is a very deep and narrow gap, meaning the distance between two adjacent electronic components along the ox direction is small, and the depth between two adjacent electronic components along the oz direction is large. For example, the distance between two adjacent electronic components along the ox direction is 0.3 mm, and the depth along the oz direction is 1.5 mm. Due to the material limitations of the insulating film 18, and based on current processes, silicone rubber and resin adhesives are difficult to completely fill the entire first gap region G1. Their elongation at break is high, making them extremely prone to breakage and unable to extend indefinitely. Consequently, the shielding film 19 covering the insulating film 18 cannot fill the entire first gap region G1. Increasing the width-to-depth ratio of the first gap region G1 to make it a second region would waste the area of ​​the circuit board 1, making it impossible to achieve miniaturization of the electronic device 01. Therefore, in this embodiment of the application, an insulating film 18 is not provided in the first interval region G1. In this way, based on the material and preparation process of the shielding film 19, for example, a liquid conductive paste can completely fill the first interval region G1, thereby forming a shielding film 19 covering the first region G1.

[0210] The circuit board assembly provided in this application embodiment, by attaching an insulating film to at least a portion of the surface of the circuit board and some electronic components, can achieve insulation isolation between the circuit board and electronic components and the shielding film. At the same time, since the shielding film is directly attached to the grounding terminal, the first gap area, part of the insulating film, the top surface of the high-heat-generating device, and at least a portion of the side surface of the high-heat-generating device, and the shielding film is electrically connected to the grounding terminal of the circuit board, a Faraday cage can be formed to provide good electromagnetic shielding for the electronic components and to provide good heat dissipation. Furthermore, since the insulating film and the shielding film can vary with the height of the electronic components, the heat from the high-heat-generating device can be quickly transferred to the shielding film, improving heat dissipation efficiency and reducing the thickness of the circuit board assembly, thereby achieving miniaturization and thinning of the electronic device, resulting in better performance of the electronic device.

[0211] Alternatively, as one possible approach, in Figure 5 On the basis of, such as Figure 7 As shown, the heat dissipation shielding structure 02 provided in this application embodiment also includes a base coating 22. The base coating 22 is at least disposed between the top surface of the first device 3 and the shielding film 19, and the base coating 22 is in contact with the top surface of the first device 3 and the shielding film 19 respectively.

[0212] Similarly, Figure 6 On the basis of, such as Figure 8 As shown, the heat dissipation shielding structure 02 provided in this application embodiment also includes a base coating 22, which is disposed at least between the top surface of the first device 3 and the shielding film 19, and between the top surface of the third device 14 and the shielding film 19.

[0213] It should be understood that the undercoating 22 being disposed at least between the top surface of the first device 3 and the shielding film 19 means that the undercoating 22 may be disposed only between the top surface of the first device 3 and the shielding film 19; or, in addition to being disposed between the top surface of the first device 3 and the shielding film 19, the undercoating 22 may also be disposed between the side surface of the first device 3 and the shielding film 19, in which case the undercoating 22 contacts the side surface of the first device 3 and the shielding film 19 respectively, without any specific limitation.

[0214] Taking the first device 3 as a cuboid plastic-encapsulated chip as an example, the base coating 22 can cover at least one of the five surfaces of the plastic-encapsulated chip other than the bottom surface.

[0215] It should be understood that the undercoating 22 being disposed at least between the top surfaces of the first device 3 and the third device 14 and the shielding film 19 means that: the undercoating 22 may be disposed only between the top surface of the first device 3 and the shielding film 19, and between the top surface of the third device 14 and the shielding film 19, in which case the undercoating 22 is in contact with the top surface of the third device 14 and the shielding film 19 respectively; or, in addition to being disposed between the top surface of the first device 3 and the shielding film 19, and the top surface of the third device 14 and the shielding film 19, the undercoating 22 may also be disposed between the side surface of the first device 3 and the shielding film 19, and between the side surface of the third device 14 and the shielding film 19, in which case the undercoating 22 is in contact with the side surface of the third device 14 and the shielding film 19 respectively, without specific limitation.

[0216] The material of the base coating 22 is not specifically limited. For example, the material of the base coating 22 can be a metal or a non-metal with high thermal conductivity, such as nickel, platinum, carbon, high-temperature resistant adhesive, etc.

[0217] It should be noted that when the material of the base coating 22 is the same as that of the shielding film 19, the boundary line between the base coating 22 and the shielding film 19 cannot be seen after the preparation is completed. The two are integrated, but they are formed independently. However, if the material of the base coating 22 is different from that of the shielding film 19, a clear boundary line can be seen.

[0218] The thickness of the base coating 22 is not specifically limited and can be at the nanometer level, depending on the materials and processes used. For example, if the base coating 22 is an aluminum metal layer, its thickness can be 0.02 μm to 1.5 μm; if it is a copper metal layer, its thickness can be 0.05 μm to 5 μm; and if it is a nickel-gold or nickel-palladium-gold layer, its thickness can be 0.02 μm to 1 μm. A thinner base coating can better improve heat dissipation for high-heat-generating devices and enhance the adhesion of the shielding film.

[0219] The coefficient of thermal expansion of the base coating 22 is not specifically limited. For example, the coefficient of thermal expansion of the base coating 22 can be greater than that of the first device 3 and less than that of the shielding film 19, so that the base coating 22 can effectively buffer stress under mechanical and thermal loads and reduce the failure risk of the first device 3.

[0220] The circuit board assembly provided in this application embodiment adds a base coating between at least one surface of a high-heat-generating device that is not provided with an insulating film and the shielding film. The base coating's properties such as buffering, oxidation resistance, breakdown resistance and corrosion resistance can improve the heat dissipation of the high-heat-generating device, reduce the failure risk of the high-heat-generating device, and enhance the adhesion effect of the shielding film.

[0221] Alternatively, as one possible approach, in Figure 5 On the basis of, such as Figure 9 As shown, in the electronic device 01 provided in this application embodiment, there is a second gap region G2 between the first device 3 and the second device 4 disposed on its left side. The width-to-depth ratio of the second gap region G2 is greater than 1:2, and the insulating film 18 can also cover the second gap region G2.

[0222] The circuit board assembly provided in this application embodiment can fill the second gap area with a large width-to-depth ratio between adjacent electronic components with silicone rubber and resin adhesive, thereby achieving coverage and isolation of electronic components and reducing the risk of short-circuit failure of electronic components.

[0223] Example 2:

[0224] Figures 10 to 16 Various electronic devices 01 to which Embodiment 2 of this application applies are shown.

[0225] like Figures 10 to 16 As shown, based on Embodiment 1, the circuit board assembly provided in this application embodiment further includes a partition 24. The partition 24 is disposed between two adjacent electronic components. The partition 24 does not contact any electronic component. The partition 24 is electrically connected to the shielding film 19 and the circuit board 1 respectively. At least a portion of the surface of the partition 24 is not provided with an insulating film 18.

[0226] In applications, a partition 24 can be placed between two adjacent electronic components. This partition 24 separates the two electronic components. Since the partition 24 is electrically connected to the shielding film 19, the partition 24 and the shielding film 19 effectively form two flange cages, with each electronic component housed within its respective flange cage. Of course, the number of partitions between two adjacent electronic components can be multiple, depending on the specific application.

[0227] In this embodiment, the partition 24 is disposed between two adjacent electronic components. The aspect ratio between the two adjacent electronic components is not specifically limited. For example, the aspect ratio between the two adjacent electronic components can be relatively large (greater than 1:2); or, the aspect ratio between the two adjacent electronic components can be relatively small (less than or equal to 1:2). It should be noted that when the partition 24 is disposed in an area with a small aspect ratio, the size of the partition 24 needs to be small, while when the partition 24 is disposed in an area with a large aspect ratio, the size of the partition 24 is not limited, depending on the actual application.

[0228] In applications, the ribs 24 can be formed together with electronic components on the mounting surface 11 of the circuit board 1 during the SMT stage.

[0229] The material and structure of the partition 24 are not specifically limited. For example, the partition 24 can be metal, such as nickel-plated stainless steel or nickel-plated stainless steel; or, the partition 24 can be metal wrapped with carbon fiber; or, the partition 24 can be metal wrapped with resin; or, the partition 24 can have the same structure as the circuit board 1. For example, the partition 24 can include a copper-clad laminate, and resin layers and copper layers disposed on both sides of the copper-clad laminate, with the resin layer located between two adjacent copper layers. In this case, the copper layer is a conductive layer, and the resin layer acts as an insulating layer. Thus, the partition 24 is conductive.

[0230] It should be noted that, if the partition 24 has the same structure as the circuit board 1, the partition 24 can be made separately and then installed on the mounting surface 11. Alternatively, the partition 24 can be made in a local area along the oz direction while the circuit board 1 is being made. That is, after the partition 24 is integrally formed with the circuit board 1, other structures can be installed. No specific limitation is made here.

[0231] The shape of the rib 24 is not specifically limited. For example, the shape of the rib 24 can be a cube, cuboid, cylinder, regular trapezoid, or inverted trapezoid.

[0232] It should be understood that the electrical connection of the partition 24 to the shielding film 19 and the circuit board 1 respectively means that at least a portion of the top surface of the partition 24 is electrically connected to the shielding film 19, and at least a portion of the bottom surface of the partition 24 is electrically connected to the mounting surface 11 of the circuit board 1. For example, as shown... Figures 10 to 16 As shown, the bottom surface of the rib 24 can be electrically connected to the mounting surface 11 via the fourth pad 25.

[0233] The circuit board assembly provided in this application embodiment provides excellent electromagnetic shielding for two adjacent electronic components through ribs, and improves the isolation by more than 50 dB.

[0234] Alternatively, as one possible approach, such as Figure 10As shown, the circuit board assembly provided in this embodiment includes a first device 3, a second device 4, a partition 24, five first solder pads 16, five first solder balls 17, two second solder pads 15, a fourth solder pad 25, a ground terminal D1, a primer coating 22, an insulating film 18, and a shielding film 19. A first gap region G1 exists between the first device 3 and the second device 4. The partition 24 is disposed in the first gap region G1 and does not contact either the first device 3 or the second device 4. The top surface and part of the side surface of the rib 24 are in direct contact with the shielding film 19. The bottom surface of the rib 24 is connected to the mounting surface 11 through the fourth pad 25. The primer coating 22 is set on the top surface of the first device 3 away from the circuit board 1. The insulating film 18 covers the top surface of the second device 4 and the side surface away from the rib 24. The shielding film 19 covers the top surface of the primer coating 22, the top surface of the rib 24, part of the side surface of the rib 24, the outer surface of the insulating film 18, and part of the mounting surface 11. The shielding film 19 is electrically connected to the grounding terminal D1.

[0235] In this embodiment, the shielding film 19 can be a film with stretchable properties, thereby enabling the shielding film 19 to directly cover the top surface of the primer coating 22, the top surface of the rib 24, part of the side surface of the rib 24, the top surface of the insulating film 18, and part of the mounting surface 11, and reducing the risk of the shielding film 19 breaking.

[0236] The circuit board assembly provided in this application embodiment has a partition rib disposed in the first interval area between the first device and the second device. At this time, the partition rib and the shielding cover together isolate the first device and the second device into their respective flange cages. The partition rib and the shielding cover are connected to form vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device and the second device, and the circuit board assembly has good performance.

[0237] Alternatively, as one possible approach, such as Figure 11 As shown, Figure 11 and Figure 10 The difference is that the insulating film 18 is filled between the side of the base coating 22 and the side of the rib 24, and is in contact with the base coating 22 and the rib 24 respectively. The insulating film 18 covers the part of the side of the rib 24 away from the first device 3, the top surface of the second device 4 and the side away from the rib 24. The shielding film 19 covers the top surface of the base coating 22, the top surface of the rib 24, the outer surface of the insulating film 18 and part of the mounting surface 11. The shielding film 19 is electrically connected to the grounding terminal D1.

[0238] The circuit board assembly provided in this application embodiment has a partition rib disposed in the first gap area between the first device and the second device. At this time, the partition rib and the shielding cover together isolate the first device and the second device into their respective flange cages. The partition rib and the shielding cover are connected to form a vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device and the second device. In addition, an insulating film is added between the partition rib and the base coating, and the insulating film on the side of the partition rib is connected to the insulating film on the second device. The insulating film can not only provide good insulation and isolation between the first device and the second device, but also support the shielding film and reduce the risk of shielding film breakage. The circuit board assembly has good performance.

[0239] Alternatively, as one possible approach, such as Figure 12 As shown, Figure 12 and Figure 10 The difference is that the insulating film 18 fills between the side of the base coating 22 and the side of the rib 24, and contacts the base coating 22 and the rib 24 respectively. The insulating film 18 covers the surface of the second device 4 except for the bottom surface. The shielding film 19 covers the top surface of the base coating 22, the top surface and part of the side of the rib 24, the outer surface of the insulating film 18, and part of the mounting surface 11. The shielding film 19 is electrically connected to the grounding terminal D1.

[0240] The circuit board assembly provided in this application embodiment has a partition rib disposed in the first interval area between the first device and the second device. At this time, the partition rib and the shielding cover together isolate the first device and the second device into their respective flange cages. The partition rib and the shielding cover are connected to form vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device and the second device, and the circuit board assembly has good performance.

[0241] Alternatively, as one possible approach, such as Figure 13 As shown, Figure 13 and Figure 11 The difference is that there is a second gap region G2 between the first device 3 and the second device 4, and the width-to-depth ratio of the second gap region G2 is greater than 1:2.

[0242] Since the distance between the first device 3 and the second device 4 is relatively large, the size of the partition 24 can be designed to be larger, which is beneficial for the manufacture and installation of the partition 24.

[0243] Furthermore, the spacing between the partition 24 and the first device along the ox direction can be set to be the same, which is beneficial for the installation of the partition 24.

[0244] It should be noted that, Figure 10 and Figure 12 The rib 24 is also applicable to the second interval zone G2, which will not be elaborated here.

[0245] The circuit board assembly provided in this application embodiment has a partition rib set in a second area with a large width-to-depth ratio between the first device and the second device. The size of the partition rib can be designed to be larger, which is beneficial for the fabrication and installation of the partition rib. The partition rib and the shielding cover together isolate the first device and the second device into their respective flange cages and conduct to form vertical electromagnetic shielding, thereby improving the shielding and heat dissipation effects and the performance of the circuit board assembly.

[0246] Alternatively, as one possible approach, such as Figure 14 As shown, the circuit board assembly provided in this embodiment includes a first device 3, a second device 4, a third device 14, two partitions 24, three first pads 16, three first solder balls 17, two second pads 15, two fourth pads 25, three third pads 20, three second solder balls 21, a ground terminal D1, two primer coatings 22, an insulating film 18, and a shielding film 19. A first gap G1 is formed between the first device 3 and the second device 4, and between the first device 3 and the third device 14. The two partitions 24 are respectively disposed in one of the first gaps G1. The first device 3, the second device 4, and the third device 14 are not in contact. The bottom surface of the partition 24 is connected to the mounting surface 11 through the fourth pad 25. A primer coating 22 is provided on the top surface of the first device 3 away from the circuit board 1, and a primer coating 22 is provided on the top surface of the third device 14 away from the circuit board 1. An insulating film 18 covers the part of the side of the partition 24 away from the first device 3, the top surface of the second device 4, and the side away from the partition 24. A shielding film 19 covers the top surface of the primer coating 22, the top surface of the partition 24, the outer surface of the insulating film 18, and part of the mounting surface 11. The shielding film 19 is electrically connected to the grounding terminal D1.

[0247] It should be noted that an insulating film 18 may also be provided on the surface of the rib 24 between the first device 3 and the third device 14, which will not be elaborated here.

[0248] The circuit board assembly provided in this application embodiment has partitions between the first device and the second device, and between the first device and the third device. The partitions and the shielding cover together isolate the first device, the second device and the third device into their respective flange cages. The partitions and the shielding cover are connected to form vertical electromagnetic shielding, thereby providing good electromagnetic shielding and heat dissipation for the first device, the second device and the third device, and the circuit board assembly has good performance.

[0249] Example 3:

[0250] Figures 15 to 11 Various electronic devices 01 to which Embodiment 3 of this application applies are shown.

[0251] like Figure 15 As shown, the circuit board assembly provided in this embodiment includes a first device 3, four second devices 4, two partitions 24, nine first pads 16, nine first solder balls 17, eight second pads 15, two fourth pads 25, two ground terminals D1, a primer coating 22, and a shielding film 19. The two second devices 4 are respectively disposed on the left and right sides of the first device 3. Each partition 24 is disposed on the side of the two second devices 4 away from the first device 3. The first device 3, the second devices, and the partitions 24 are not in contact. The bottom surface of each partition 24 is connected to the mounting surface 11 through the fourth pad 25. The primer coating 22 is disposed on the top surface of the first device 3 away from the circuit board 1. The shielding film 19 covers all surfaces and is electrically connected to the ground terminals D1.

[0252] In application, the interval between the first device 3 and the second device 4 can be either the first interval or the second interval; no specific limitation is made here.

[0253] It should be noted that, Figure 15 The shielding membrane 19 in the middle needs to have the property of being able to be supported by the ribs without collapsing.

[0254] The circuit board assembly provided in this application embodiment supports the shielding film with ribs, forming a cavity between it and the second device. The second device can dissipate heat through air. At the same time, the shielding film is in contact with the first device, which can achieve good heat dissipation for the first device. In addition, by omitting the insulating film, it can achieve good electromagnetic shielding and heat dissipation effects. The circuit board assembly can be made thinner and smaller, and the process is simplified, thereby enabling the electronic device to be thinner and smaller, and the electronic device has better performance.

[0255] Alternatively, as one possible approach, such as Figure 16 As shown, Figure 16 and Figure 15 The difference is that the mounting surface 11 of the circuit board 1 is also provided with at least one reinforcing structure 33, the reinforcing structure 33 is located on at least one side of each second device 4, and the height of the reinforcing structure 33 along the oz direction is less than or equal to the height of the second device 4 along the oz direction.

[0256] In applications, the reinforcing structure 33 can be made of resin. Specifically, the reinforcing structure 33 can be formed by dispensing resin onto at least one side of each second device 4 using a dispensing process.

[0257] The circuit board assembly provided in this application embodiment can enhance the welding strength between the second device and the circuit board through the reinforcement structure.

[0258] Alternatively, as one possible approach, such as Figure 17 As shown, Figure 17 and Figure 15 The difference is that a partition 24 is provided on each of the left and right sides of the second device 4.

[0259] It should be noted that, Figure 17 Only the second device 4 is shown in the figure, but there are actually other electronic components adjacent to the second device 4.

[0260] The circuit board assembly provided in this application embodiment can reduce the clearance space between adjacent electronic components and does not require additional shielding around the second device, thereby achieving a thinner and lighter circuit board assembly.

[0261] Example 4:

[0262] Figure 18 An electronic device 01 to which Embodiment 3 of this application applies is shown.

[0263] exist Figure 5 On the basis of, such as Figure 18 As shown, the heat dissipation shielding structure 02 provided in this application embodiment also includes a graphite film 27, which covers the outer surface of the shielding film 19.

[0264] In the application, the side of the graphite film 27 facing away from the shielding film 19 is flat, and along the ox axis, the size of the graphite film 27 is different at various positions along the oz direction, so that the graphite film 27 can cover various positions of the shielding film 19 and improve the heat dissipation effect.

[0265] The thickness of the graphite film 27 is not specifically limited. For example, the thickness of the graphite film 27 along the oz direction can be 30μm to 100μm. The thickness of the graphite film 27 can be different for electronic components of different heights.

[0266] The circuit board assembly provided in this application embodiment utilizes the heat dissipation effect of the graphite film to form heat dissipation surfaces on both the side of the graphite film away from the shielding film and the side surface of the graphite film. This allows the heat from the shielding film corresponding to the electronic components to be quickly dispersed to the surface of the graphite, thereby reducing the local temperature of the shielding film, avoiding the generation of hot and cold spots, improving the heat dissipation effect on the electronic components, reducing the generation of thermal stress, and preventing the shielding film from deforming.

[0267] Alternatively, as one possible approach, please refer to [further details]. Figure 18 The heat dissipation shielding structure 02 provided in this application embodiment also includes thermal conductive gel 28, which is disposed between at least a portion of the shielding film 19 and the graphite film 27.

[0268] Because the shielding film 19 and the insulating film 18 are conformal covers, significant undulations may occur in localized areas between adjacent electronic components, either due to gaps or height differences between them. When the graphite film 27 is placed over the shielding film 19, it may not completely fill the undulating areas, potentially creating air gaps between them and affecting heat transfer efficiency. Therefore, by placing a thermally conductive gel 28 between the shielding film 19 and the graphite film 27, the fluidity of the gel can fill the undulating areas, preventing air gaps.

[0269] The filling position of the thermal conductive gel 28 is not specifically limited. For example, the thermal conductive gel 28 can be provided at one position between the shielding film 19 and the graphite film 27; or, the thermal conductive gel 28 can be provided at multiple positions between the shielding film 19 and the graphite film 27.

[0270] It is understandable that the placement and area of ​​the thermal conductive gel 28 can be adjusted according to the actual situation, and no specific limitations are made here.

[0271] The circuit board assembly provided in this application embodiment can improve heat conduction efficiency by adding a thermally conductive condenser between the shielding film 19 and the graphite film 27. The thermal conductivity of the thermally conductive gel is greater than that of air, thereby further improving the heat dissipation effect.

[0272] Example 5:

[0273] Figures 19 to 21 Various methods for fabricating circuit board assemblies are shown.

[0274] Figure 19 This application illustrates a method for manufacturing a circuit board assembly applicable to an embodiment of the present application. It should be noted that, in the circuit board assembly of this embodiment, only the first region z1 of the mounting surface 11 of the circuit board 1 is involved, and the first region z1 is provided with a heat dissipation shielding structure 02.

[0275] like Figure 19 As shown, the method for manufacturing a circuit board assembly provided in this application includes the following steps:

[0276] S11. For example Figure 19 As shown in Figure (a), a circuit board 1 is provided.

[0277] The circuit board 1 has a mounting surface 11.

[0278] S12. For example Figure 19As shown in Figure (b), in the first region z1, a first device 3, six second devices 4, a third device 14, three ground terminals D1 and two partitions 24 are formed by SMT process.

[0279] Wherein, a first gap region G1 is provided between the first device 3 and the second device 4, and a first gap region G1 is provided between the second device 4 and the third device 14. Figure 19 (not shown in Figure b), a second gap region is provided between the second device 4 and the third device 14. Figure 19 (not shown in Figure (b)) Both the first and second interval zones are provided with ribs 24.

[0280] S13. For example Figure 19 As shown in Figure (c), release layers 29 are formed on the top surface and all sides of the first device 3, the top surface and all sides of the third device 14, the three grounding terminals D1, the top surface and at least part of the sides of the two partitions 24, and the first gap area G1.

[0281] It should be noted that when the rib 24 is made of metal, the release layer 29 may not be formed on the top surface of the rib 24.

[0282] In applications, the release layer 29 may include release paper, which may specifically be polycarbonate (PC), PI, and polyethylene terephthalate (PET), etc.

[0283] Furthermore, the release layer 29 may also include a release agent coated on one side of the release paper. The release agent may be silicone oil, which has properties such as low adhesion and easy peeling. In practical use, the release agent faces the structure to which the release layer needs to be attached and bonds the release paper to that structure.

[0284] Therefore, before applying the insulating film, pre-protection should be carried out on the area where the insulating film will be removed. For example, cover it with release paper or with a release paper containing easily peelable silicone oil, and then apply the insulating film. When removing the insulating film later, simply apply the release paper around the outer edge to peel off the release layer along with the insulating film. This can shorten the time required to remove the insulating film and minimize damage to the structure from which the insulating film needs to be removed.

[0285] It should be noted that when the release layer is peeled off along with the insulating film, the release paper in the release layer will be completely removed along with the insulating film. The release agent can be completely removed or some may remain. The remaining release agent has no adverse effect on the circuit board assembly.

[0286] S14. For example Figure 19As shown in Figure (d), insulating material is covered on the mounting surface 11 of the first region, the surface of the first device 3 other than the bottom surface connected to the mounting surface 11, the surface of the second device 4 other than the bottom surface connected to the mounting surface 11, the surface of the third device 14 other than the bottom surface connected to the mounting surface 11, the grounding terminal D1, and the surface of the partition 24 other than the bottom surface connected to the mounting surface 11 to form an insulating film 18.

[0287] In applications, insulating film 18 can be prepared by any of the following processes: spraying, vacuum lamination, hot pressing, etc.

[0288] In one implementation, the insulating material can be a thin film. After obtaining the circuit board 1 with the electronic components installed, a high-temperature environment (e.g., 120°C to 150°C) can be provided to heat the film to soften it. Then, using a soft-surface pressing structure combined with vacuum pressing technology, the softened film is pressed onto the position where it needs to be coated. At the same time, a vacuum is drawn on the side of the circuit board 1 so that the softened film can cover and fill the required position.

[0289] Optionally, before heating the film, the thickness of the film can be slightly larger than the thickness of the final insulating film 18. This can prevent the film from being torn during subsequent pressing and vacuuming processes, thereby achieving continuous coverage of the insulating film 18.

[0290] In another implementation, the insulating material can be insulating adhesive. After obtaining the circuit board 1 with the electronic components installed, the insulating adhesive can be sprayed onto the areas requiring coating using a spraying method, and then cured to form an insulating film 18. Since the spraying process does not exert any pulling force on the insulating adhesive, but only allows it to adhere to various locations, the insulating adhesive can be sprayed more effectively, especially for the first gap area G1 with a small aspect ratio. Specifically, direct spraying or oblique spraying can be used for spraying.

[0291] For example, insulating adhesive can be vacuum hot-pressed at approximately 180°C and 2 MPa for a period of time to form an insulating film 18. It should be noted that the insulating film does not have adhesive properties; it only acquires adhesive properties at high temperatures (e.g., 180°C). At the same time, the pressure (e.g., 2 MPa) is to make the insulating film 18 conform to the location where it needs to be coated.

[0292] Optionally, the minimum thickness of the insulating film 18 should be no less than 10 μm to avoid damage to the insulating film 18 during subsequent operations, thereby affecting the insulation performance.

[0293] S15. Figure 19As shown in Figure (e), the insulating film 18 and at least part of the release layer 29 on the top surface and all sides of the first device 3, the top surface and all sides of the third device 14, the surface of the ground terminal D1, the first spacer area G1, the top surface and at least part of the surface of the rib 24 are removed.

[0294] In this application, laser engraving can be used to remove the insulating film 18 and at least part of the release layer 29. The laser engraving diameter can be approximately 40 μm, offering high precision. It can accurately remove the insulating film 18 and at least part of the release layer 29 at specific locations without easily damaging or causing excessive damage to the desired structure. The process is relatively simple, easy to operate, and fast, thus improving efficiency. It should be noted that the laser engraving temperature must not be too high to prevent damage to electronic components.

[0295] Of course, other methods can also be used, such as physical removal of the insulating film 18 and at least part of the release layer 29. For example, a blade can be used to cut the insulating film 18 and at least part of the release layer 29, etc. Those skilled in the art can choose flexibly according to the actual situation, and there is no limitation thereto.

[0296] Optionally, such as Figure 19 As shown in Figure (e), in this embodiment of the application, a laser engraving source can be used above the location where the release layer 29 is located. Based on the previously drawn circuit diagram, laser engraving (LD) is performed on the positions of the insulating film 18 corresponding to the perimeter of the release layer 29. Subsequently, the insulating film 18 at these positions, along with the release layer 29, can be removed together. Laser engraving along the perimeter of the release layer 29 significantly reduces the time required compared to laser engraving the entire release layer 29 and its insulating film 18. Furthermore, given the easy-to-peel nature of the release layer 29, only the perimeter needs to be laser engraved and then peeled off to remove the release layer 29 and its insulating film 18. Reducing the laser engraving time lowers the risk of excessive laser temperature, thus benefiting the performance protection of electronic components.

[0297] Therefore, after laser-etching away part of the insulating film 18, these locations are easy to form a shielding film 19. At the same time, the insulating film 18 can also insulate and isolate the covered areas, and the improved thermal conductivity of the insulating film 18 can be utilized. In addition, the insulating film 18 can generally vary in height according to the electronic components, covering each electronic component in a conformal manner, so as to reduce the space occupied by the insulating film 18 in the oz direction, which facilitates the miniaturization design of the circuit board assembly.

[0298] S16. For example Figure 19As shown in Figure (f), a shielding film 19 is formed by covering the top surface and all sides of the first device 3, the top surface and all sides of the third device 14, the grounding terminal D1, the first gap area G1, the top surface and at least part of the sides of the partition 24, and the insulating film 18 away from the outer surface of the circuit board 1 with shielding material, so that the shape of the shielding film 19 matches the shape of the insulating film 18, and the shielding film 19 is electrically connected to the grounding terminal D1.

[0299] In applications, the shielding film 19 can be formed through high-temperature vacuum pressing, spraying, sputtering, or other methods, without specific limitations.

[0300] In one implementation, if the shielding material is a thin film before forming the shielding film 19, it can be covered by a high-temperature vacuum pressing process on the top surface of the first device 3, the top surface of the third device 14, the grounding terminal D1, the first interval area G1, the top surface of the partition 24, and the outer surface of the insulating film 18 away from the circuit board 1 to form the shielding film 19.

[0301] In another implementation, if the shielding material is metal particles before forming the shielding film 19, the metal can be melted by high temperature and then covered at the above-mentioned position by spraying, sputtering or spin coating. After the metal solidifies, the shielding film 19 is formed, and the thickness of the shielding film 19 is greater than or equal to the skin depth.

[0302] In another implementation, if the shielding material is a liquid conductive paste before forming the shielding film 19, it can be applied to the above-mentioned position by spraying or sputtering. After the conductive paste solidifies, the shielding film 19 is formed.

[0303] The shape of the shielding film 19 generally matches the above-mentioned positions, so that the shielding film 19 can cover these positions in a conformal manner. At the same time, the conformal coverage of the insulating film 18 can make the distance between electronic components of different heights and the shielding film 19 similar, so as to reduce the occurrence of taller components being close to the shielding film 19 and shorter components being far away from the shielding film 19, and minimize the distance difference between each electronic component and the shielding film 19 as much as possible.

[0304] It should be noted that the circuit board 1 in the embodiments of this application can be a single circuit board 1. However, in actual production, a single circuit board 1 is usually not processed separately. Instead, the materials are assembled from the supplied boards. For example, multiple circuit boards 1 are formed on a large frame board, and then cutting is performed between adjacent circuit boards 1 and the excess frame board is cut off to form a single circuit board 1 for use, that is, slitting the finished product.

[0305] S17. For example Figure 19 As shown in Figure (g), a circuit board assembly is formed.

[0306] The circuit board assembly fabrication method provided in this application first forms the required structure on the circuit board using SMT technology, then forms a release layer on certain surfaces of some structures, and then covers it with an insulating film that conforms to the shape of each structure. After processing the edge positions corresponding to the insulating film and the release layer, the insulating film at these positions is removed, ensuring that the process of removing the insulating film causes as little damage as possible to each structure. Then, a conforming shielding film is covered. At this time, the shielding film deposition has no sharp cuts, and the clearance between the shielding film and each structure does not need to be large, which reduces the risk of electromagnetic wave leakage and effectively improves the heat dissipation effect. In addition, this fabrication method is simple and easy to implement, which is conducive to industrial production.

[0307] Figure 20 This paper illustrates a method for manufacturing a circuit board assembly applicable to embodiments of this application. It should be noted that the circuit board assembly in this embodiment involves a first region z1 and a second region z2 on the mounting surface 11 of the circuit board 1. The first region z1 is provided with a heat dissipation shielding structure 02 and is located in the middle of the mounting surface 11. The second region z2 is located at the edge of the mounting surface 11, and the first region z1 and the second region z2 are connected. The second region z2 is provided with external components such as spring contacts, switches, BTB terminals, test terminals, and electronic components requiring debugging.

[0308] like Figure 20 As shown, the method for manufacturing a circuit board assembly provided in this application includes the following steps:

[0309] S21. As Figure 20 As shown in Figure (a), a circuit board 1 is provided.

[0310] The circuit board 1 has a mounting surface 11.

[0311] S22. For example Figure 19 As shown in Figure (b), in the first region z1, a first device 3, seven second devices 4, three ground terminals D1 and two partitions 24 are formed by SMT process, and in the second region z2, a second device 4 is formed by SMT process.

[0312] Wherein, the first device 3 and the second device 4 are separated by a first gap region G1, and the second device 4 is separated by a first gap region (G1). Figure 20 (not shown in Figure b), a second spacing region is provided between the second devices 4. Figure 20 (not shown in Figure (b)) Both the first and second interval zones are provided with ribs 24.

[0313] S23. For example Figure 20As shown in Figure (c), in the first region z1, release layers 29 are formed on the top surface and all sides of the first device 3, the grounding terminal D1, the top surface of the partition 24, and the first interval region G1. In the second region z2, a protective cover 30 is provided around the second device 4.

[0314] In application, the material of the protective cover 30 can be metal or non-metal, as long as it ensures that the second device 4 in the second region z2 does not come into contact with the heat dissipation shielding structure formed subsequently.

[0315] S24. For example Figure 20 As shown in Figure (d), insulating material is applied to the mounting surface 11 of the first region, the surface of the first device 3 other than the bottom surface connected to the mounting surface 11, the surface of the second device 4 other than the bottom surface connected to the mounting surface 11, the grounding terminal D1, and the surface of the partition 24 other than the bottom surface connected to the mounting surface 11 to form an insulating film 18.

[0316] It should be noted that the second region z2 does not need to form an insulating film 18.

[0317] S25. For example Figure 20 As shown in Figure (e), the top surface and all sides of the first device 3, the surface of the ground terminal D1, the first spacer region G1, the insulating film 18 on the top surface of the partition 24, and at least part of the release layer 29 are removed from the first region z1.

[0318] S26. For example Figure 20 As shown in Figure (f), in the first region z1, the top surface and all sides of the first device 3, the ground terminal D1, the first interval region G1, the top surface of the partition 24, and the insulating film 18 are away from the outer surface of the circuit board 1 to form a shielding film 19.

[0319] In the application, it can be Figure 20 The structure shown in Figure (e) is placed in the reaction chamber 31 and a shielding film 19 is formed through processes such as PVD, CVD, laser metal circuit (LMC), and chemical immersion plating. The process temperature can be less than 150°C, which can form a shielding film 19 of sufficient thickness while reducing damage to electronic components due to high temperature.

[0320] It should be noted that, especially for the shielding film coating process in the area near the insulating film, the temperature must not be too high; for example, the temperature needs to be less than 150°C.

[0321] Among them, PVD: the pressure can be greater than 400V, and the temperature can be 90℃~150℃.

[0322] LMC: Low-temperature coating, with a maximum temperature of less than or equal to 90℃.

[0323] CVD: The temperature can be 90℃~150℃.

[0324] Chemical immersion plating: Metal ion solution or liquid conductive paste is directly applied to the top surface and all surfaces of the first device 3, the grounding terminal D1, the first interval area G1, the top surface of the partition 24, and the outer surface of the insulating film 18 away from the circuit board 1 by spin coating or spraying. Then, a metal element layer is obtained through displacement reaction or chemical precipitation reaction to remove impurities and form a shielding film 19.

[0325] S27. For example Figure 20 As shown in Figure (g), the protective cover 30 is removed to form a circuit board assembly.

[0326] The protective cover 30 protects external components such as contact springs, switches, BTB terminals, test terminals, and electronic components requiring debugging in advance, preventing damage to these components during subsequent processes. Furthermore, since there's no concern about damage to external components, excessive spacing between the structures in the first region z1 and the second region z2 is unnecessary. The protective cover is not applied during laser engraving but removed only at the end, maximizing space utilization, minimizing obstacle avoidance, and eliminating concerns about accidental contact or obstruction of electronic components in the second region z2. This effectively achieves miniaturization of the circuit board assembly.

[0327] The circuit board assembly fabrication method provided in this application first forms the required structure on the circuit board using SMT technology, and then protects the electronic components in the second region (excluding the first region) that do not require a heat dissipation shielding structure with a protective cover. This prevents the electronic components in the second region from being affected by the heat dissipation shielding structure formation process, while reducing the clearance space. At the same time, a shielding film is formed by methods such as physical vapor deposition, chemical vapor deposition, and chemical impregnation to protect the electronic components in the first region from the heat dissipation shielding structure formation process as much as possible, resulting in better performance of the circuit board assembly. In addition, this fabrication method is simple and easy to implement, which is conducive to industrial production.

[0328] Figure 21 This application illustrates a method for manufacturing a circuit board assembly to which this invention applies. Figure 21 and Figure 20 The difference is:

[0329] S35. For example Figure 21 As shown in Figure (e), after removing the insulating film 18 and at least part of the release layer 29 from the top surface and all sides of the first device 3 in the first region z1, the surface of the ground terminal D1, the first spacer region G1, and the top surface of the rib 24, a primer coating 22 is also formed on the top surface of the first device 3.

[0330] S36. For example Figure 21As shown in Figure (f), a shielding film 19 is formed in the first region z1, on the outer surface of the base coating 22, the grounding terminal D1, the first interval region G1, the top surface of the partition 24, and the insulating film 18 away from the outer surface of the circuit board 1.

[0331] In applications, the material of the primer coating 22 can be at least one of high melting point metals (e.g., tungsten, molybdenum, nickel and platinum), high temperature resistant adhesives, composite powders with exothermic properties (e.g., nickel-aluminum powder), carbon, etc.

[0332] The thickness of the base coating 22 can be at the nanometer level.

[0333] The primer coating 22 can be prepared by processes such as spraying, plating, chemical plating, and PVD. The primer coating 22 has a short formation time and causes less damage to the structure it covers.

[0334] It should be noted that in PVD, CVD and LMC processes, the primer coating 22 can provide heat dissipation protection, that is, protect high-heat-generating devices from damage caused by high temperatures during long-term processing in the later stages, so as to maintain the performance of high-heat-generating devices.

[0335] In the chemical immersion plating process, the primer coating 22 can provide acid and alkali protection, that is, protect the high-heat-generating device from the damage caused by the acid and alkali of the subsequent long-term processing, so that the performance of the high-heat-generating device can be maintained well.

[0336] The circuit board assembly preparation method provided in this application involves spraying a primer coating onto the top surface of a high-heat-generating device after forming an insulating film and before forming a shielding film. The primer coating material undergoes a chemical reaction with the material of the first device at high temperature, forming a micro-metallurgical bond, which enhances the bonding strength between the primer coating and the first device. At the same time, the surface of the primer coating is rougher than the surface of the first device. This irregularity increases the mechanical interlocking between the primer coating and the first device, improves the bonding strength, and the rough surface can suppress and control shrinkage stress, reduce the risk of primer coating peeling, and improve the heat dissipation, breakdown resistance, and corrosion resistance of the first device. In addition, it also strengthens the adhesion of the subsequent shielding film.

[0337] The above only introduces some content related to the inventive point. Other content can be obtained by referring to relevant technologies, and will not be described in detail here.

[0338] It should be understood that the above description is merely to help those skilled in the art better understand the embodiments of this application, and is not intended to limit the scope of the embodiments of this application. Based on the examples given above, those skilled in the art can obviously make various equivalent modifications or changes. For example, some steps in various embodiments of the method may be optional, or new steps may be added; or any combination of two or more of the above embodiments. Such modifications, changes, or combinations also fall within the scope of the embodiments of this application.

[0339] It should also be understood that the above description of the embodiments of this application focuses on highlighting the differences between the various embodiments. Any similarities or differences not mentioned can be referred to each other. For the sake of brevity, they will not be repeated here.

[0340] It should also be understood that the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0341] It should also be understood that the methods, situations, categories, and classifications of embodiments in this application are for the convenience of description only and should not constitute a special limitation. Various methods, categories, situations, and features in embodiments can be combined without contradiction.

[0342] It should also be understood that, in the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced by each other, and the technical features in different embodiments can be combined to form new embodiments according to their inherent logical relationships.

[0343] Finally, it should be noted that the above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A circuit board assembly, characterized in that, The circuit board assembly includes a circuit board and a heat dissipation shielding structure. The circuit board has a mounting surface, which includes a first area. The first area is on which various electronic components and the heat dissipation shielding structure are mounted. The electronic components include at least an adjacent first device and a second device. The heat dissipation range of the first device is greater than that of the second device. The first device and the second device are separate and spaced apart. The space between the first device and the second device includes a first spacer area. The width-to-depth ratio of the first spacer area is less than or equal to 1:

2. The heat dissipation shielding structure includes: An insulating film covers all locations except for the top surface of the first device away from the mounting surface and at least a portion of the side surface connected to the top surface, the grounding terminal, and the first spacing area. The insulating film is designed to vary in height according to the electronic component. A shielding film covers the top surface of the first device away from the mounting surface and at least a portion of its side surface connected to the top surface, the grounding terminal, the first gap area, and the side of the insulating film facing away from the circuit board. The shape of the shielding film matches the shape of the electronic components and the insulating film, and the shielding film is electrically connected to the grounding terminal.

2. The circuit board assembly according to claim 1, characterized in that, The spacer between the first device and the second device further includes a second spacer, the width-to-depth ratio of which is greater than 1:2, and the insulating film also covers the second spacer.

3. The circuit board assembly according to claim 1 or 2, characterized in that, The first region is also provided with a partition, at least one of the partitions is provided in the first interval area and / or the second interval area, the partition is not in contact with the first device and the second device, the insulating film does not cover the top surface of the partition away from the mounting surface, the shielding film covers at least part of the top surface of the partition, and the partition is electrically connected to the shielding film and the mounting surface respectively.

4. The circuit board assembly according to claim 3, characterized in that, A rib is provided in the gap area between the first device and the second device. The insulating film covers at least the top surface of the second device away from the mounting surface and the side of the second device away from the rib. The shielding film covers at least the top surface of the first device, the top surface of the rib and a portion of the side surface connected to the top surface, the surface of the insulating film away from the circuit board, and a portion of the mounting surface.

5. The circuit board assembly according to claim 3, characterized in that, A rib is provided in the gap area between the first device and the second device. The insulating film covers at least the side of the rib away from the first device, the top surface of the second device away from the mounting surface, and the side of the second device away from the rib. The shielding film covers at least the top surface of the first device, the top surface of the rib, the side of the insulating film away from the circuit board, and part of the mounting surface.

6. The circuit board assembly according to claim 3, characterized in that, A rib is provided in the gap area between the first device and the second device. The insulating film covers at least the surface of the second device except for the bottom surface connected to the mounting surface. The shielding film covers at least the top surface of the first device, the top surface of the rib and a portion of the side surface connected to the top surface, the side of the insulating film away from the circuit board, and a portion of the mounting surface.

7. The circuit board assembly according to claim 3, characterized in that, The electronic component also includes a third component adjacent to the first component. The third component is disposed on the side of the first component away from the second component. The third component is separate from and spaced apart from the first component. The heat generation range of the third component is the same as that of the first component, but the heat generation of the third component is less than that of the first component. A rib is provided in the gap area between the first device and the second device, and a rib is provided in the gap area between the first device and the third device. The insulating film covers at least the side of the rib between the first device and the second device away from the first device, the top surface of the second device away from the mounting surface, and the side of the second device away from the rib. The shielding film covers at least the top surface of the first device, the top surfaces of the two ribs, the side of the insulating film away from the rib, the side of the insulating film away from the circuit board, and part of the mounting surface.

8. A circuit board assembly, characterized in that, The circuit board assembly includes a circuit board and a heat dissipation shielding structure. The circuit board has a mounting surface, which includes a first area. The first area is on which various electronic components, the heat dissipation shielding structure, and at least one partition are mounted. The electronic components include at least an adjacent first device and a second device. The heat dissipation range of the first device is greater than that of the second device. The first device and the second device are separate and spaced apart. The partition is located on at least one side of the second device and is not in contact with the second device. The heat dissipation shielding structure includes a shielding film that covers at least the top surface of the first device away from the mounting surface, the top surface of the rib away from the mounting surface, and part of the mounting surface. There is a space between the shielding film and the second device, and the shielding film is electrically connected to the grounding terminal of the circuit board.

9. The circuit board assembly according to claim 8, characterized in that, The second device has a rib on the side away from the first device, and the shielding film covers at least the top surface of the first device, the top surface of the rib, and the side of the rib away from the second device.

10. The circuit board assembly according to claim 8, characterized in that, The second device has a rib on each side, and the shielding film covers at least the top surface of the first device, the top surface of the rib, and the side of the rib away from the second device.

11. The circuit board assembly according to any one of claims 3 to 10, characterized in that, The material of the rib is metal; Alternatively, the material of the reinforcing bar includes carbon fiber and metal, with the metal wrapped around the surface of the carbon fiber; Alternatively, the material of the rib may include resin and metal, with the metal wrapped around the surface of the resin; Alternatively, the material of the reinforcing rib may include a copper-clad laminate, and a resin layer and a copper layer disposed on symmetrical sides of the copper-clad laminate, wherein the resin layer is located between two adjacent copper layers.

12. The circuit board assembly according to any one of claims 1 to 11, characterized in that, The heat dissipation shielding structure also includes a base coating, which is disposed at least between the top surface of the first device and the shielding film, and the material of the base coating is different from the material of the shielding film.

13. The circuit board assembly according to claim 12, characterized in that, When the material of the base coating is aluminum, the thickness of the base coating perpendicular to the mounting surface is 0.02 μm to 1.5 μm; When the material of the base coating is copper, the thickness of the base coating perpendicular to the mounting surface is 0.05μm to 5μm; When the material of the base coating is a nickel-gold alloy or a nickel-palladium-gold alloy, the thickness of the base coating perpendicular to the mounting surface is 0.02 μm to 1 μm.

14. The circuit board assembly according to any one of claims 1 to 13, characterized in that, The heat dissipation shielding structure also includes a graphite film, which covers the side of the shielding film away from the circuit board.

15. The circuit board assembly according to claim 14, characterized in that, The heat dissipation shielding structure also includes a thermally conductive gel, which is disposed between at least a portion of the shielding film and the graphite film.

16. The circuit board assembly according to any one of claims 1 to 15, characterized in that, The first device is a packaged chip, and the first region is further provided with a first pad and a first solder ball. The first solder ball is disposed between the packaged chip and the first pad. The packaged chip is electrically connected to the mounting surface in sequence through the first solder ball and the first pad. The shielding film is insulated from the first solder ball and the first pad respectively.

17. The circuit board assembly according to any one of claims 1 to 16, characterized in that, The mounting surface further includes a second region. The first region is located in the middle of the mounting surface, and the second region is located at the edge of the mounting surface. The second region is provided with at least one electronic component, and the surface of the electronic component is not provided with the heat dissipation shielding structure.

18. An electronic device, characterized in that, The electronic device includes a circuit board assembly as described in any one of claims 1 to 17.

19. A method for manufacturing a circuit board assembly, characterized in that, include: A circuit board is provided; wherein the circuit board has a mounting surface, the mounting surface including a first region; At least a variety of electronic components are installed in the first area; wherein, the electronic components include at least an adjacent first device and a second device, the heat generation range of the first device is greater than the heat generation range of the second device, the first device and the second device are separate and spaced apart, the space between the first device and the second device includes a first spacer area, and the width-to-depth ratio of the first spacer area is less than or equal to 1:

2. Release layers are formed on the top surface of the first device on the side away from the mounting surface and at least a portion of the side surface connected to the top surface, the ground terminal of the circuit board, and the first gap area. An insulating film is formed by covering the surface of the first device (excluding the bottom surface connected to the mounting surface), the grounding terminal, and the portion of the mounting surface in the first region with insulating material; wherein the insulating film is designed to vary in height according to the electronic component. Remove the top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the insulating film and release layer of the first spacing region; A shielding film is formed by covering the top surface and at least part of the side surface of the first device, the grounding terminal, the first gap area, and the side of the insulating film away from the circuit board with a shielding material; wherein the shape of the shielding film matches the shape of the electronic component and the insulating film, and the shielding film is electrically connected to the grounding terminal; The circuit board assembly is formed.

20. The method for manufacturing a circuit board assembly according to claim 19, characterized in that, The installation of at least a variety of electronic components in the first region includes: At least one partition rib is also formed in the first region; wherein the partition rib is disposed on at least one side of the second device and the partition rib is not in contact with the second device; The step of covering the surface of the first device (excluding the bottom surface connected to the mounting surface), the grounding terminal, and the portion of the mounting surface in the first region with insulating material to form an insulating film includes: The insulating material is applied to the surface of the first device (excluding the bottom surface connected to the mounting surface), the grounding terminal, the portion of the mounting surface in the first region, and the surface of the partition (excluding the bottom surface connected to the mounting surface) to form the insulating film. The removal of the top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the insulating film and release layer of the first gap region includes: Remove the top surface and at least part of the side surface of the first device, the surface of the grounding terminal, the insulating film and release layer of the first spacing area, and at least remove the insulating film of the top surface of the partition rib on the side away from the mounting surface; The step of covering the top surface and at least part of the sides of the first device, the grounding terminal, the first gap region, and the side of the insulating film away from the circuit board with shielding material to form a shielding film includes: The shielding material is applied to at least the top surface and at least a portion of the sides of the first device, the grounding terminal, the first gap area, the side of the insulating film away from the circuit board, and a portion of the top surface of the rib to form the shielding film.

21. The method for manufacturing a circuit board assembly according to claim 19 or 20, characterized in that, The removal of the top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the insulating film and release layer of the first gap region includes: The top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the edge of the insulating film and the release layer of the first interval area are laser-etched around the perimeter using a laser engraving process. Then, the top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the insulating film and the release layer of the first interval area are peeled off.

22. The method for manufacturing a circuit board assembly according to claim 19 or 20, characterized in that, The mounting surface further includes a second region, wherein the first region is located at the middle of the mounting surface, the second region is located at the edge of the mounting surface, and at least a second device is mounted in the second region; The formation of a release layer on the top surface of the first device away from the mounting surface and at least a portion of the side surface connected to the top surface, the ground terminal of the circuit board, and the first gap area includes: The release layer is formed on the top surface and at least part of the side surface of the first device, the ground terminal, and the first gap area in the first region, and a protective cover is formed around the second device in the second region; The circuit board assembly includes: Remove the protective cover to form the circuit board assembly.

23. The method for manufacturing a circuit board assembly according to claim 19 or 20, characterized in that, After removing the top surface and at least part of the side surfaces of the first device, the surface of the grounding terminal, the insulating film and release layer of the first spacing region, and before covering the top surface and at least part of the side surfaces of the first device, the grounding terminal, the first spacing region and the insulating film away from the circuit board with shielding material to form a shielding film, the preparation method further includes: At least a primer coating is formed on the top surface of the first device; The step of covering the top surface and at least part of the sides of the first device, the grounding terminal, the first gap region, and the side of the insulating film away from the circuit board with shielding material to form a shielding film includes: The shielding material is applied to the surfaces of the base coating (excluding the surface in contact with the first device), the grounding terminal, the first gap area, and the surface of the insulating film away from the circuit board to form the shielding film.

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