Embedded component circuit board and processing method thereof

Abstract

The invention discloses a circuit board with embedded components and a processing method thereof. The embedded component circuit board comprises a multi-layer core board, a plurality of prepregs, a plurality of heating components and a heat dissipation medium block, the heating components comprise chips, the prepregs are fixedly connected between the core boards, the heating components are embedded in the prepregs, and the heat dissipation medium block is fixedly connected between the prepregs. The prepreg is provided with a first metalized via hole which is connected with the circuit layer of the core plate and the welding surface of the heating component; the circuit board is provided with a heat dissipation medium block and a prepreg, the prepreg is provided with a heat dissipation groove, the heat dissipation medium block is arranged in the heat dissipation groove, one end of the heat dissipation medium block abuts against the heating component, the other end of the heat dissipation medium block is provided with an extension part, the extension part is exposed out of at least one board edge of the circuit board, and the board edge comprises an outer board edge and / or a hollow board edge. According to the circuit board embedded with the components, heat in the circuit board can be quickly dissipated out of the circuit board through the heat dissipation medium block, so that the heat dissipation efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of circuit board processing technology, and in particular to a circuit board with embedded components and its processing method. Background Technology

[0002] Embedded component circuit boards (PCBs) embed electronic components within the PCB itself, rather than mounting them on the surface or sides. They achieve circuit integration and miniaturization by embedding components such as resistors, chips, or transistors within a multilayer substrate. However, the significant heat generated by the heat-generating components within these PCBs cannot be dissipated through airflow or external heat sinks. Instead, they rely solely on the thermal conductivity of the PCB material, impacting their lifespan and reliability.

[0003] Currently, related technologies improve the heat dissipation efficiency of circuit boards by increasing copper thickness, optimizing material selection, adopting three-dimensional heat dissipation architectures, or adding heat dissipation vias. However, methods such as increasing copper thickness and optimizing material selection are limited by the thermal conductivity of the circuit board materials themselves and cannot significantly improve heat dissipation efficiency. On the other hand, methods such as adopting three-dimensional heat dissipation architectures and adding heat dissipation vias are limited by the space of the circuit board, and these methods often need to span multiple core boards. The thermal conductivity of the dielectric layer between the core boards directly limits the overall heat dissipation in the vertical direction. Summary of the Invention

[0004] This application provides a circuit board with embedded components and its processing method to solve the technical problem of low heat dissipation efficiency in existing circuit boards with embedded components due to the limited thermal conductivity of their own materials.

[0005] In a first aspect, this application provides a circuit board for embedded components, including a multilayer core board, a plurality of prepregs, a plurality of heat-generating components and a heat dissipation medium block. The heat-generating components include chips. The prepregs are fixedly connected between the core boards. The heat-generating components are embedded in the prepregs. The prepregs are provided with a first metallized via that connects the circuit layer of the core board to the welding surface of the heat-generating components. The prepreg has a heat dissipation groove, the heat dissipation medium block is disposed in the heat dissipation groove, one end of the heat dissipation medium block abuts against the heat-generating component, and the other end of the heat dissipation medium block has an extension, the extension being exposed at least one edge of the circuit board, the edge including an outer edge and / or a hollowed-out edge.

[0006] The embedded component circuit board provided in this application, during operation, has its core board's circuit layer electrically connected to the soldering surface of the heat-generating component via a first metallized via, ensuring the heat-generating component is in a powered-on state. As the heat-generating component's operating time increases, it continuously generates a large amount of heat. Since one end of the heat dissipation medium block abuts against the heat-generating component, and the other end of the heat dissipation medium block has an extension exposed at least one edge of the circuit board, the heat from the heat-generating component can be quickly conducted to the heat dissipation medium block and then rapidly dissipated to the outside of the circuit board. This rapidly reduces the operating temperature of the heat-generating component, improving its reliability and lifespan. By embedding the heat-generating component within a prepreg and connecting it using a heat dissipation medium block, both efficient heat dissipation and stable fixation of the heat-generating component are achieved.

[0007] The soldering surface of the heat-generating component is electrically connected to the circuit layer of the core board through a first metallized via, thereby improving the integration and electrical connection reliability of the embedded component circuit board, reducing external leads, and lowering signal transmission loss and electromagnetic interference. Since the board edge includes an outer board edge and / or a hollowed-out board edge, the extension at the other end of the heat dissipation medium block can be exposed on the outer board edge of the circuit board when there is sufficient external space, or on the hollowed-out board edge when the circuit board uses a hollow design, thus fully utilizing the internal space of the circuit board. The embedded component circuit board of this application overcomes the problem of low heat dissipation efficiency in traditional heat dissipation technologies due to the heat dissipation medium block being limited by the thermal conductivity of the circuit board material itself, achieving a significant improvement in the heat dissipation efficiency of the embedded component circuit board.

[0008] In some embodiments of the first aspect, the prepreg includes a first prepreg layer, a second prepreg layer and a third prepreg layer stacked sequentially, the first metallized via is disposed in the third prepreg layer, the heating element is disposed in the second prepreg layer, the heat dissipation groove is disposed in the first prepreg layer or between the first prepreg layer and the target core board, and the target core board is a core board fixedly connected to the first prepreg layer.

[0009] In some embodiments of the first aspect, the extension of the heat dissipation medium block is bent toward the side closer to the circuit board; and / or, the extension of the heat dissipation medium block is provided with an auxiliary heat dissipation component.

[0010] In some embodiments of the first aspect, a first plane on the heat dissipation medium block that contacts the heat-generating element covers a second plane on the heat-generating element that contacts the heat dissipation medium block; and / or, the length of the extension of the heat dissipation medium block is not less than a preset length.

[0011] In some embodiments of the first aspect, the core board is provided with a second metallized via, the second metallized via connecting the upper circuit layer and the lower circuit layer of the core board.

[0012] Secondly, this application provides a method for processing the aforementioned embedded component circuit board, comprising: Based on preset milling parameters, the prepreg is milled to create embedded grooves corresponding to the heat-generating components and heat dissipation grooves corresponding to the heat dissipation medium block. Based on the preset stacking structure parameters of the embedded component circuit board, the prepreg, multilayer core board, heat-generating components and heat dissipation medium block are stacked to obtain a pre-stacked board, wherein the heat-generating components are embedded in the embedding groove and the heat dissipation medium block is placed in the heat dissipation groove. The pre-stacked boards are pressed and post-processed to obtain a circuit board with embedded components.

[0013] The processing method provided in this application produces embedded component circuit boards with high heat dissipation efficiency, flexible design, and no impact on the original circuit layout. It overcomes the problem of low heat dissipation efficiency in traditional heat dissipation technologies, where the heat dissipation efficiency of the heat dissipation medium is limited by the thermal conductivity of the circuit board material itself, thus significantly improving the heat dissipation efficiency of embedded component circuit boards. This processing method is highly flexible and customizable, adapting to the heat dissipation requirements of embedded component circuit boards of different sizes, power ratings, and layouts. By adjusting the material, size, and position of the heat dissipation medium, precise matching of the heating characteristics of different embedded components can be achieved, further improving heat dissipation efficiency. Furthermore, the manufacturing process is simple and can be implemented on existing circuit board production lines without introducing new equipment or processes, which helps reduce production costs and promotes widespread application.

[0014] In some embodiments of the second aspect, the step of milling grooves on the prepreg based on preset milling parameters to mill grooves corresponding to the embedded grooves of the heat-generating components and the heat dissipation grooves corresponding to the heat dissipation medium blocks includes: Based on the preset milling parameters, embedding grooves corresponding to the heat-generating components are milled in the second semi-cured layer of the prepreg, and heat dissipation grooves corresponding to the heat dissipation medium block are milled in the first semi-cured layer of the prepreg; the preset milling parameters include first milling parameters corresponding to the actual size parameters of the heat-generating components, and second milling parameters corresponding to the actual size parameters of the heat dissipation medium block.

[0015] In some embodiments of the second aspect, the pre-stacked board is obtained by stacking the prepreg, multilayer core board, heat-generating components, and heat dissipation medium block based on the preset stacking structure parameters of the embedded component circuit board to obtain a pre-stacked board, including: Based on the high-temperature sintering process of nano-silver or the high thermal conductivity adhesive molding process, the connecting surface of the heat-generating element is fixedly connected to one end of the heat dissipation medium block. One end of the heat dissipation medium block, on which the heat-generating component is fixed, is placed in the heat dissipation groove of the prepreg, and the extension of the heat dissipation medium block is placed outside the groove opening of the heat dissipation groove. The core board is stacked on both sides of the prepreg to obtain the pre-stacked board.

[0016] In some embodiments of the second aspect, before stacking the prepreg, multilayer core board, heat-generating components, and heat dissipation medium block, the method further includes: The heat dissipation medium is processed into a heat dissipation medium material that meets the target size parameter requirements, and the protection area of ​​the heat dissipation medium material is marked. The protection area of ​​the heat dissipation medium material is then protected by high-temperature adhesive to obtain the heat dissipation medium block. The target size parameter requirements are determined based on a preset correspondence between the actual size parameters of the heat-generating component and the target size parameter requirements. The protection area is located in the extension of the heat dissipation medium block. The post-processing includes: laser peeling off the high-temperature adhesive on the extension of the heat dissipation medium block.

[0017] In some embodiments of the second aspect, the pressing and post-processing of the pre-stacked plates includes: The pre-stacked plates are pressed together to obtain a pressed plate; Based on a preset drilling file, the press plate is drilled and metallized to create a first metallized through hole and a second metallized through hole; and / or, the extension of the heat dissipation medium block is bent toward the side closer to the press plate. Attached Figure Description

[0018] Figure 1 This is a side view of the embedded component circuit board shown in an embodiment of this application; Figure 2 This is a top view of the embedded component circuit board shown in an embodiment of this application; Figure 3 This is a schematic diagram illustrating the structure of an embedded component circuit board in which the extension of the heat dissipation medium block is exposed on the edge of the outer board. Figure 4 This is a schematic diagram illustrating the structure of an embedded component circuit board in which the extension of the heat dissipation medium block is exposed on the edge of the cutout board. Figure 5 This is a schematic diagram of the layered structure of the heat dissipation medium block in the embedded component circuit board, as shown in an embodiment of this application. Figure 6This is a schematic diagram of the layered structure of the prepreg in a circuit board with embedded components, as shown in an embodiment of this application. Figure 7 This is a schematic diagram of the bent structure of the heat dissipation medium block extension in a circuit board with embedded components, as shown in an embodiment of this application. Figure 8 This is a schematic flowchart illustrating the manufacturing method of a circuit board with embedded components according to an embodiment of this application; Figure 9 This is a schematic diagram showing the application position of high-temperature adhesive in the manufacturing method of an embedded component circuit board according to an embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] refer to Figure 1 As shown, the embedded component circuit board disclosed in this application includes a multilayer core board, a plurality of prepregs, a plurality of heat-generating components, and a heat dissipation medium block. The heat-generating components include chips. The prepregs are fixedly connected between the core boards. The heat-generating components are embedded in the prepregs. The prepregs are provided with a first metallized via connecting the circuit layer of the core board and the soldering surface of the heat-generating components. The prepregs are provided with heat dissipation grooves. The heat dissipation medium block is disposed in the heat dissipation grooves. One end of the heat dissipation medium block abuts against the heat-generating components. The other end of the heat dissipation medium block is provided with an extension. The extension is exposed on at least one edge of the circuit board. The edge includes an outer edge and / or a hollowed-out edge.

[0021] In this embodiment, as Figure 2 As shown, multiple extensions can be exposed on the same outer panel edge; such as Figure 3 As shown, the extension can be exposed at multiple outer panel edges; such as Figure 4 As shown, the extension can be exposed on the edge of the cutout board. The heat dissipation medium block enables heat to be efficiently conducted from the inside of the circuit board to the external environment, reducing the operating temperature of heat-generating components while maintaining the compactness of the circuit board. This not only solves the problem that embedded components in the prior art cannot achieve auxiliary heat dissipation through contact with air or external heat sinks, but also improves the overall heat dissipation efficiency of the circuit board, as well as the reliability and durability of the product.

[0022] During circuit board operation, the circuit layer of the core board is electrically connected to the soldering surface of the heat-generating component through the first metallized via, putting the heat-generating component into a powered-on state. As the operating time of the heat-generating component increases, it continuously generates a large amount of heat. Because one end of the heat dissipation medium block abuts against the heat-generating component, and the extension of the other end of the heat dissipation medium block is exposed at least one edge of the circuit board, the heat from the heat-generating component can be quickly conducted to the heat dissipation medium block and then quickly dissipated to the outside of the circuit board. This rapidly reduces the operating temperature of the heat-generating component, improving its reliability and lifespan. By embedding the heat-generating component within the prepreg and connecting it using the heat dissipation medium block, efficient heat dissipation and stable fixation of the heat-generating component are achieved simultaneously.

[0023] The soldering surface of the heat-generating component is electrically connected to the circuit layer of the core board through the first metallized via, which improves the integration and electrical connection reliability of the embedded component circuit board, reduces external leads, and lowers signal transmission loss and electromagnetic interference. The extension at the other end of the heat dissipation medium block can be exposed on the outer edge of the circuit board when there is sufficient external space, or on the cutout edge of the circuit board when the circuit board adopts a cutout design, thereby making full use of the internal space of the circuit board.

[0024] Optionally, the heat dissipation medium block can be made entirely of conductive materials, entirely of non-conductive materials, or a combination of conductive and non-conductive materials. For example, such as... Figure 5 As shown, the heat dissipation medium block includes a first conductive layer, a second conductive layer, and an insulating layer, with the insulating layer disposed between the first and second conductive layers. The conductive layer can be a metal or a high-conductivity resin, such as copper or conductive polyaniline; the insulating layer can be a thermally conductive insulating resin, such as highly thermally conductive epoxy resin. The multi-layered structure of the heat dissipation medium block not only provides a good heat conduction path to enhance heat dissipation efficiency but also provides electrical isolation through the insulating layer to prevent short circuits, and enables circuit connection functions through the first and second conductive layers. This layered structure allows the heat dissipation medium block to possess both heat dissipation and circuit connection functions, improving the overall performance and safety of the embedded component circuit board.

[0025] In one embodiment, such as Figure 6 As shown, the prepreg includes a first prepreg layer, a second prepreg layer, and a third prepreg layer stacked sequentially. A first metallized via is disposed in the third prepreg layer, a heat-generating component is disposed in the second prepreg layer, and a heat dissipation groove is disposed in the first prepreg layer or between the first prepreg layer and the target core board. The target core board is a core board fixedly connected to the first prepreg layer. It should be noted that... Figure 6 The extension of the heat dissipation medium block is exposed on the outer edge of the circuit board. Figure 6The view direction is the view direction directly facing the extension.

[0026] In this embodiment, the second semi-cured layer may have embedded grooves for mounting heat-generating components. The target core board may have limiting grooves for mounting heat dissipation medium blocks. The limiting grooves of the target core board can limit and fix the heat dissipation medium blocks, making the connection between the heat dissipation medium blocks and the target core board more secure.

[0027] By separately setting a first semi-cured layer, a second semi-cured layer, and a third semi-cured layer, the production process of this embedded component circuit board is made more efficient. Since the heat dissipation groove is located between the first semi-cured layer or between the first semi-cured layer and the target core board, and the second semi-cured layer has embedded grooves for heat-generating components, the heat dissipation medium block and heat-generating components can be better accommodated during the lamination process of this embedded component circuit board. This reduces interlayer stress, improves the alignment accuracy and mechanical stability of the embedded component circuit board structure, and helps prevent displacement or damage of heat-generating components and heat dissipation medium blocks during lamination, thereby improving the yield and durability of the circuit board.

[0028] In one embodiment, such as Figure 7 As shown, the extension of the heat dissipation medium block is bent toward the side closer to the circuit board; and / or, the extension of the heat dissipation medium block is provided with an auxiliary heat dissipation component.

[0029] In this embodiment, the extension of the heat dissipation medium block is bent towards the side closer to the circuit board. This ensures that the extension does not occupy too much external space and effectively reduces the volume of the circuit board with embedded components. Bending the extension towards the circuit board makes the external heat dissipation portion more compact, reducing space occupation and avoiding interference with other components. This embodiment optimizes the circuit board layout through bending design, improves mechanical strength, and ensures the continuity of the heat dissipation path, thereby enhancing overall heat dissipation efficiency and reliability. By providing auxiliary heat dissipation components in the extension of the heat dissipation medium block, the heat dissipation rate of the extension can be further accelerated, thereby optimizing the heat dissipation effect of the circuit board with embedded components.

[0030] In one embodiment, the first plane on the heat dissipation medium block that contacts the heat-generating component covers the second plane on the heat-generating component that contacts the heat dissipation medium block; the length of the extension of the heat dissipation medium block is not less than a preset length.

[0031] In this embodiment, the first plane on the heat dissipation medium block that contacts the heat-generating component covers the second plane on the heat-generating component that contacts the heat dissipation medium block, increasing the heat conduction area. This allows the heat generated by the heat-generating component to be directly conducted to the heat dissipation medium block to the maximum extent, and the high thermal conductivity of the heat dissipation medium block is used to quickly conduct the heat to the outside of the circuit board. The longer the exposed length of the extension, the larger the heat dissipation area and the higher the heat dissipation efficiency. In this embodiment, the length of the extension is set to be no less than a preset length to ensure heat dissipation efficiency; the preset length can be set according to actual needs, for example, 2mm.

[0032] In one embodiment, the core board is provided with a second metallized via, which connects the upper and lower circuit layers of the core board. By providing the second metallized via, electrical connections can be smoothly achieved between different circuit layers of the embedded component circuit board; at the same time, the metallized via can assist heat transfer and improve heat dissipation efficiency; and the second metallized via can also enhance the structural strength of the circuit board and prevent delamination or breakage caused by external forces.

[0033] To obtain the embedded component circuit board corresponding to the above embodiments, this application also provides a processing method for the embedded component circuit board. For example... Figure 8 As shown, the processing method of the embedded component circuit board in this embodiment includes steps S1 to S3, which are described in detail below: Step S1: Based on preset milling parameters, mill grooves are made on the prepreg to create embedded grooves corresponding to the heat-generating components and heat dissipation grooves corresponding to the heat dissipation medium block.

[0034] In this step, the preset milling parameters are determined based on the dimensions of the heat-generating components and the heat dissipation medium block. For example, the preset milling parameters for the embedded groove are the same as the dimensions of the heat-generating components, and the preset milling parameters for the heat dissipation groove are the same as the dimensions of the heat dissipation medium block. The milling operation of the prepreg can be achieved using CNC milling or laser milling.

[0035] In one embodiment, step S1 includes: Based on preset milling parameters, embedding grooves corresponding to heat-generating components are milled in the second semi-cured layer of the prepreg, and heat dissipation grooves corresponding to heat dissipation media blocks are milled in the first semi-cured layer of the prepreg. The preset milling parameters include first milling parameters corresponding to the actual size parameters of the heat-generating components and second milling parameters corresponding to the actual size parameters of the heat dissipation media blocks.

[0036] In this embodiment, the prepreg is milled in layers to facilitate the standardized layout of the circuit board, improve the rationality of the layout, meet the processing requirements of the heat-generating components and heat dissipation medium block in the subsequent lamination process, reduce the thermal or mechanical stress during the lamination process of the circuit board, and improve the reliability and service life of the circuit board.

[0037] In one embodiment, prior to step S1, the prepreg can be pre-processed, including cutting and drilling positioning holes. In the cutting step, the first, second, and third prepregs are cut according to the laminated structure and the dimensions and quantity requirements of the Engineering MI (Manufacturing Components). In the drilling positioning holes step, positioning holes are drilled for the first, second, and third prepregs according to the drilling parameters specified in the Engineering MI drilling file. After step S1, the prepregs can be inspected. In the inspection step, precision instruments such as calipers and a two-dimensional measuring instrument are used to measure the slot dimensions to confirm that the slot dimensions are qualified and free of burrs and residual adhesive.

[0038] Step S2: Based on the preset stacking structure parameters of the embedded component circuit board, the prepreg, multilayer core board, heat-generating components and heat dissipation medium block are stacked to obtain a pre-stacked board, wherein the heat-generating components are embedded in the embedding groove and the heat dissipation medium block is placed in the heat dissipation groove.

[0039] In this step, a pre-stacked board is obtained by stacking the prepreg, multilayer core board, heat-generating components, and heat dissipation medium block. The heat-generating components are embedded in the embedding grooves in the pre-stacked board, and the heat dissipation medium block is placed in the heat dissipation grooves. At the same time, one end of the heat dissipation medium block abuts against the heat-generating components, realizing the pre-contact between the heat dissipation medium block and the heat-generating components, and providing a heat conduction path for the heat-generating components in the circuit board to conduct heat to the heat dissipation medium block.

[0040] Optionally, during the pre-stacked board processing, a first semi-cured layer is first stacked on the bottom core board so that the heat dissipation medium block passes through the heat dissipation groove; then a second semi-cured layer is stacked on the first semi-cured layer so that the heat-generating components pass through the embedded groove; then a third semi-cured layer is stacked on the second semi-cured layer, and finally the top core board is stacked on the third semi-cured layer.

[0041] In one embodiment, step S2 includes: fixing the connecting surface of the heat-generating component to one end of the heat dissipation medium block based on a nano-silver high-temperature sintering process or a high thermal conductivity adhesive molding process; placing one end of the heat dissipation medium block with the heat-generating component fixed thereon in the heat dissipation groove of the prepreg, with the extension of the heat dissipation medium block placed outside the groove opening of the heat dissipation groove; and stacking the core board on both sides of the prepreg to obtain the pre-stacked board.

[0042] In this embodiment, for the high-temperature sintering process of nano-silver, under high temperature (200℃-300℃) and high pressure (5MPa-20MPa) conditions, the connecting surface of the heating element and the heat dissipation medium block are solid-state sintered together using nano-silver sintering paste to permanently bond them together. The thermal conductivity of this method (240W / MK) is much higher than that of tin solder (60W / MK) and conductive adhesive (20 W / MK).

[0043] For high thermal conductivity encapsulation processes, liquid or paste-like high thermal conductivity encapsulating adhesives are used to encapsulate heat-generating components and heat dissipation media through dispensing, potting, or other methods. The encapsulated material is then heated and cured. The adhesive acts as a binder and a thermally conductive bridge between the heat-generating components and the heat dissipation media. This method is relatively simple, convenient, and low-cost.

[0044] In one embodiment, before step S2, the method may further include: obtaining the dimensional parameters of the heat-generating component; determining the dimensional parameters of the heat dissipation medium block based on the dimensional parameters of the heat-generating component and a preset dimensional conversion function; and processing the heat dissipation medium block according to the dimensional parameters of the heat dissipation medium block.

[0045] In this embodiment, by customizing the size of the heat dissipation medium block according to the size parameters of the heat-generating components, a perfect match between the heat dissipation medium block and the heat-generating components is ensured, thereby optimizing the heat dissipation effect and structural adaptability.

[0046] Optionally, the manufacturing process of the heat dissipation medium block includes material cutting, drilling positioning holes, printing character frames or solder mask frames, milling the heat dissipation medium block, browning, and inspection. In the material cutting step, material cutting is performed according to the quantity requirements of the Engineering MI (Manufacturing Components). In the positioning hole drilling step, positioning holes are drilled according to the drilling parameters specified in the Engineering MI drilling file. In the character frame or solder mask printing step, characters are printed or solder mask is printed according to the Engineering MI requirements. On both sides of the heat dissipation medium block that need to extend to the outside of the circuit board, the positions for applying high-temperature adhesive are clearly marked to facilitate precise high-temperature adhesive application. In the heat dissipation medium block milling step, CNC milling or laser milling is performed according to the quantity and size requirements of the Engineering MI to ensure the heat dissipation medium block meets the size specifications. In the browning step, the heat dissipation medium block is fully browned to improve the bonding force between the heat dissipation medium block and the prepreg during the lamination process. In the inspection step, the dimensions and surface quality of the heat dissipation medium block are comprehensively inspected to ensure that the heat dissipation medium block meets the design requirements.

[0047] Optionally, the core board manufacturing process includes inner layer pretreatment, inner layer circuit fabrication, inner layer etching, inner layer stripping, and automated optical inspection. In the inner layer pretreatment step, an inner layer roughening method is used to roughen and clean the copper surface. In the inner layer circuit fabrication step, dry film is applied to both sides of the board, and the pattern is transferred using direct laser imaging according to the engineering MI inner layer circuit file. After development, the inner layer circuit pattern is obtained. In the inner layer etching step, matching parameters are selected based on the inner layer copper thickness in the engineering MI to etch away the copper surface without dry film protection. In the inner layer stripping step, the dry film on the board surface is removed using a horizontal stripping machine. In the automated optical inspection step, an automated optical inspection machine is used to inspect the etched and stripped inner circuits.

[0048] Step S3: Press and post-process the pre-stacked board to obtain the embedded component circuit board.

[0049] In this step, the pre-stacked boards can be pressed according to the engineering MI processing requirements to ensure that the surface of the pressed board is free of quality defects such as wrinkles and dents. Through the cooperation of the first, second, and third semi-cured layers, the heat dissipation medium block and heat-generating components can be better accommodated during the pressing process, reducing interlayer stress and thus improving the structural alignment accuracy and mechanical stability of the pressed board. The third semi-cured layer can ensure the filling of the gaps around the heat-generating components and heat dissipation medium block, and separate the heat-generating components from the copper layer of the top core board, preventing the pressure applied during pressing from acting directly on the heat-generating components. It also facilitates the connection of the solder pads on the heat-generating components to the circuit copper layer of the top core board through laser drilling and hole metallization, forming an electrical connection.

[0050] In one embodiment, step S3 includes: pressing the pre-stacked plates together to obtain a pressed plate; drilling and metallizing the pressed plate based on a preset drilling file to process a first metallized through hole and a second metallized through hole; and / or bending the extension of the heat dissipation medium block toward the side closer to the pressed plate.

[0051] In this embodiment, when processing the first metallized via, the drilling position of the laminating plate is determined, and a hole is drilled at the drilling position of the laminating plate to process the initial via. The depth of the initial via is equal to the distance between the solder surface of the heating element in the laminating plate and the drilling surface of the laminating plate. The drilling operation can be performed according to the engineering MI drilling file, using the specified board drilling parameters. The two ends of the initial via are respectively connected to the solder surface of the heating element and the circuit layer of the drilling surface of the laminating plate. Before the initial via is metallized, the solder pads of the heating element and the circuit layer of the drilling surface of the laminating plate cannot be electrically connected. After the initial via is metallized, the first metallized via can conduct the circuit layer of the solder surface of the heating element and the drilling surface of the laminating plate, thereby connecting the heating element to the circuit of the drilling surface of the laminating plate. The copper thickness range of the metallized via can be set according to actual needs, for example, the copper thickness range of the metallized via is 25μm-30μm.

[0052] When determining the drilling positions of the laminating plate, the process first involves acquiring images of the laminating plate and the drill tape file. Then, the image coordinates of the positioning holes in the laminating plate corresponding to the acquired images and the theoretical coordinates in the corresponding drill tape file are determined. A coordinate transformation function is then determined based on the image coordinates and theoretical coordinates of the positioning holes. Finally, the drilling positions of the laminating plate are determined based on the coordinate transformation function and the theoretical coordinates of the drilling positions in the drill tape file. By combining image acquisition and drill tape file processing with a coordinate transformation function, the drilling positions are accurately determined, reducing errors caused by traditional alignment methods and improving drilling accuracy and the alignment of metallized vias. This helps ensure reliable connections between the pads of heat-generating components and the circuit layers, improving the electrical performance and yield of the circuit board, and is suitable for the processing of high-density interconnect circuit boards.

[0053] In one embodiment, such as Figure 9 As shown, before step S2, the process further includes: processing the heat dissipation medium material into a heat dissipation medium material that meets the target size parameter requirements, marking the protective area of ​​the heat dissipation medium material, and applying high-temperature adhesive to protect the protective area of ​​the heat dissipation medium material to obtain the heat dissipation medium block. The target size parameter requirements are determined based on a preset correspondence between the actual size parameters of the heat-generating component and the target size parameter requirements. The protective area is located in the extension of the heat dissipation medium block. The post-processing in step S3 includes laser peeling off the high-temperature adhesive on the extension of the heat dissipation medium block.

[0054] In this embodiment, during laser peeling, as required by the engineering MI document, a laser device is used to irradiate the high-temperature adhesive covering the heat sink block, completely exposing the protected area without any residual adhesive or other defects, facilitating subsequent heat dissipation or bending operations. By applying high-temperature adhesive to the protected area, the adhesive protects the heat sink block, preventing the prepreg in the protected area from adhering to it. The heat sink block is a stretchable thermally conductive material, and its extension can be bent to reduce the overall length of the circuit board or to install a heat dissipation device to accelerate heat dissipation. Furthermore, depending on space and the required extension length of the heat sink block, the extension can be bent using a bending machine or manually. The bending angle and length must be precisely controlled according to specific design requirements to ensure the heat sink block does not affect the overall spatial structure. After bending, the bent portion must be inspected for appearance and dimensions to ensure it meets design requirements.

[0055] The embedded component circuit board processing method provided in this application produces circuit boards with high heat dissipation efficiency, flexible design, and no impact on the original circuit layout. This innovative design overcomes the limitations of traditional heat dissipation technologies, where direct contact between the heat dissipation medium block and the embedded heat-generating components is restricted by circuit design or prepreg, resulting in inefficient heat dissipation. This significantly improves the heat dissipation efficiency of embedded component circuit boards. The processing method for this embedded component circuit board is highly flexible and customizable, adapting to the heat dissipation requirements of embedded component circuit boards of different sizes, power ratings, and layouts. By adjusting the material, size, and position of the heat dissipation medium block, precise matching of the heat generation characteristics of different embedded components can be achieved, further improving heat dissipation efficiency. The manufacturing process is relatively simple and can be implemented on existing circuit board processing lines without introducing new equipment or processes, which helps reduce processing costs and promotes widespread application.

[0056] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit the scope of protection of this application. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application for those skilled in the art.

Claims

1. A circuit board for embedded components, characterized in that, It includes a multilayer core board, several prepregs, several heating elements and a heat dissipation medium block. The heating elements include chips. The prepregs are fixedly connected between the core boards. The heating elements are embedded in the prepregs. The prepregs are provided with a first metallized via connecting the circuit layer of the core board and the welding surface of the heating elements. The prepreg has a heat dissipation groove, the heat dissipation medium block is disposed in the heat dissipation groove, one end of the heat dissipation medium block abuts against the heat-generating component, and the other end of the heat dissipation medium block has an extension, the extension being exposed at least one edge of the circuit board, the edge including an outer edge and / or a hollowed-out edge.

2. The embedded component circuit board as described in claim 1, characterized in that, The prepreg includes a first prepreg layer, a second prepreg layer, and a third prepreg layer stacked sequentially. The first metallized via is disposed in the third prepreg layer. The heating element is disposed in the second prepreg layer. The heat dissipation groove is disposed in the first prepreg layer or between the first prepreg layer and the target core board. The target core board is a core board that is fixedly connected to the first prepreg layer.

3. The embedded component circuit board as described in claim 1, characterized in that, The extension of the heat dissipation medium block is bent toward the side closer to the circuit board; and / or, the extension of the heat dissipation medium block is provided with an auxiliary heat dissipation component.

4. The embedded component circuit board as described in claim 1, characterized in that, The first plane on the heat dissipation medium block that contacts the heat-generating component covers the second plane on the heat-generating component that contacts the heat dissipation medium block; and / or, the length of the extension of the heat dissipation medium block is not less than a preset length.

5. The embedded component circuit board as described in claim 1, characterized in that, The core board is provided with a second metallized via, which connects the upper circuit layer and the lower circuit layer of the core board.

6. A method for processing a circuit board with embedded components as described in any one of claims 1 to 5, characterized in that, include: Based on preset milling parameters, the prepreg is milled to create embedded grooves corresponding to the heat-generating components and heat dissipation grooves corresponding to the heat dissipation medium block. Based on the preset stacking structure parameters of the embedded component circuit board, the prepreg, multilayer core board, heat-generating components and heat dissipation medium block are stacked to obtain a pre-stacked board, wherein the heat-generating components are embedded in the embedding groove and the heat dissipation medium block is placed in the heat dissipation groove. The pre-stacked boards are pressed and post-processed to obtain a circuit board with embedded components.

7. The processing method for a circuit board with embedded components as described in claim 6, characterized in that, The step of milling grooves on the prepreg based on preset milling parameters to create embedded grooves corresponding to the heat-generating components and heat dissipation grooves corresponding to the heat dissipation medium block includes: Based on the preset milling parameters, embedding grooves corresponding to the heat-generating components are milled in the second semi-cured layer of the prepreg, and heat dissipation grooves corresponding to the heat dissipation medium block are milled in the first semi-cured layer of the prepreg; the preset milling parameters include first milling parameters corresponding to the actual size parameters of the heat-generating components, and second milling parameters corresponding to the actual size parameters of the heat dissipation medium block.

8. The processing method of the circuit board with embedded components as described in claim 6, characterized in that, The pre-stacked board is obtained by stacking the prepreg, multilayer core board, heat-generating components, and heat dissipation medium block based on the preset stacking structure parameters of the embedded component circuit board, including: Based on the high-temperature sintering process of nano-silver or the high thermal conductivity adhesive molding process, the connecting surface of the heat-generating element is fixedly connected to one end of the heat dissipation medium block. One end of the heat dissipation medium block, on which the heat-generating component is fixed, is placed in the heat dissipation groove of the prepreg, and the extension of the heat dissipation medium block is placed outside the groove opening of the heat dissipation groove. The core board is stacked on both sides of the prepreg to obtain the pre-stacked board.

9. The processing method of the circuit board with embedded components as described in claim 6, characterized in that, Before stacking the prepreg, multilayer core board, heat-generating components, and heat dissipation medium block, the following steps are also included: The heat dissipation medium is processed into a heat dissipation medium material that meets the target size parameter requirements, and the protection area of ​​the heat dissipation medium material is marked. The protection area of ​​the heat dissipation medium material is then protected by high-temperature adhesive to obtain the heat dissipation medium block. The target size parameter requirements are determined based on a preset correspondence between the actual size parameters of the heat-generating component and the target size parameter requirements. The protection area is located in the extension of the heat dissipation medium block. The post-processing includes: laser peeling off the high-temperature adhesive on the extension of the heat dissipation medium block.

10. The processing method of the circuit board with embedded components as described in claim 6, characterized in that, The pressing and post-processing of the pre-stacked plates includes: The pre-stacked plates are pressed together to obtain a pressed plate; Based on a preset drilling file, the press plate is drilled and metallized to create a first metallized through hole and a second metallized through hole; and / or, the extension of the heat dissipation medium block is bent toward the side closer to the press plate.

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