Embedded copper block circuit board with vertical interconnect structure

Abstract

The utility model relates to a kind of embedded copper block circuit board with vertical interconnection structure, including first circuit layer, second circuit layer, third circuit layer and fourth circuit layer being sequentially stacked from top to bottom, and embedded copper block being set between second circuit layer and third circuit layer, the embedded copper block includes the base portion being horizontally arranged and the first vertical conductive column being extended upwards from the base portion and electrically connected to the first circuit layer, and / or the second vertical conductive column being extended downwards from the base portion and electrically connected to the fourth circuit layer;The first vertical conductive column and second vertical conductive column are all solid conductive column body.The utility model provides a kind of embedded copper block circuit board with vertical interconnection structure, to improve the heat dissipation efficiency and electrical interconnection performance of circuit board in thickness direction.

Description

Technical Field

[0001] This utility model relates to the field of printed circuit board manufacturing technology, and specifically to an embedded copper block circuit board with a vertical interconnect structure. Background Technology

[0002] In the manufacture of electronic devices, especially high-power circuit components, embedded copper structures are often used to enhance heat dissipation and current transmission capabilities. A common implementation involves horizontally embedding the copper block into the inner layer structure of the circuit board. This type of structure primarily relies on the copper block for heat diffusion and conductivity in the planar direction, while in the direction perpendicular to the circuit board, heat and current transfer often requires multiple layers of different materials or additional interconnect structures.

[0003] This heat and electrical conduction path, which relies on interlayer transitions, easily introduces additional contact thermal resistance and interface impedance, thus limiting overall heat dissipation efficiency and current transmission capacity. Furthermore, the process of embedding copper blocks after creating windows in already laminated circuit boards also faces challenges in controlling positioning accuracy and ensuring reliable interface bonding. Therefore, the industry desires a buried copper solution that can achieve vertical thermal management and electrical interconnection more directly and efficiently in terms of structure. Utility Model Content

[0004] In view of this, the present invention provides an embedded copper block circuit board with a vertical interconnect structure, which aims to improve the heat dissipation efficiency and electrical interconnect performance of the circuit board in the thickness direction.

[0005] The objective of this utility model is achieved through the following technical solution: An embedded copper block circuit board with a vertical interconnect structure includes a first circuit layer, a second circuit layer, a third circuit layer, and a fourth circuit layer stacked sequentially from top to bottom, and an embedded copper block disposed between the second circuit layer and the third circuit layer. The embedded copper block includes a horizontally disposed base portion and a first vertical conductive post extending upward from the base portion and electrically connected to the first circuit layer, and / or a second vertical conductive post extending downward from the base portion and electrically connected to the fourth circuit layer; both the first vertical conductive post and the second vertical conductive post are solid conductive posts.

[0006] By integrating vertically extending solid conductive pillars onto a horizontal substrate, a three-dimensional interconnect network extending throughout the thickness of the circuit board is constructed. The horizontal substrate is primarily responsible for heat dissipation and high-current conduction in the planar direction, while the vertical conductive pillars establish a direct, low-resistance path from the core of the circuit board to the surface and even the bottom layer. This three-dimensional structure significantly shortens the distance from the heat source to the heat dissipation endpoint, reduces overall thermal resistance, and allows heat accumulated at the embedded copper block to be quickly and efficiently conducted to the outer surface of the circuit board, and dissipated into the environment through possible additional heat dissipation components, thereby effectively controlling the operating temperature of high-power devices. In terms of electrical performance, this structure provides extremely low DC impedance and minimal loop inductance, meeting the requirements of high-current transmission and improving the return path of high-frequency signals, thus enhancing signal integrity. Compared to traditional circuit boards with only horizontal embedded copper structures, this three-dimensional interconnect method solves the problems of interlayer thermal isolation and poor electrical connection, achieving a synergistic improvement in heat dissipation and current carrying capacity. Furthermore, this structure integrates the main vertical interconnect functions into the embedded copper block body without taking up too much additional wiring space, which is conducive to achieving high-density integration and miniaturization of electronic devices. At the same time, its structural form has good compatibility with existing mature circuit board manufacturing processes, such as electroplating and via filling, making it easy to implement and promote.

[0007] Preferably, the upper end face of the first vertical conductive post is directly electrically and thermally connected to the lower surface of the first circuit layer.

[0008] The first vertical conductive post and the first circuit layer employ a direct physical contact. This direct electrical and thermal connection interface avoids the additional thermal resistance and contact resistance that might be introduced by using intermediate adhesive materials, creating a highly efficient channel for heat transfer from the vertical conductive post to the first circuit layer and for current flow. It ensures that the performance of thermal management and electrical connection is not compromised by the limitations of the interface material, resulting in more direct and significant heat dissipation and conductivity. Simultaneously, this direct electrical and thermal connection structure simplifies alignment and connection steps in the manufacturing process, helping to improve production yield and reduce process complexity, structurally guaranteeing the reliability and consistency of the interconnection.

[0009] Preferably, the lower end face of the second vertical conductive post is directly electrically and thermally connected to the upper surface of the fourth circuit layer.

[0010] By establishing direct electrical and thermal connections between the second vertical conductive pillar and the fourth circuit layer, an efficient heat and current outlet is created at the bottom of the circuit board. This design allows heat from the embedded copper block to be transferred not only upwards to the first circuit layer but also simultaneously downwards to the fourth circuit layer, achieving a bidirectional heat dissipation path and enhancing the redundancy and overall heat dissipation capacity of the cooling system. In terms of electrical connectivity, it provides another low-impedance vertical interconnect channel, helping to further reduce the impedance of the entire power distribution network and providing more optional, high-quality return paths for signals, thereby improving the stability and reliability of the circuit board under complex operating conditions. The bidirectional vertical interconnect structure results in a more balanced heat management and current distribution.

[0011] Preferably, the first vertical conductive post extends upward to the upper surface of the first circuit layer and forms an exposed heat dissipation pad.

[0012] Extending the first vertical conductive post directly to the outermost layer of the circuit board and forming an exposed pad effectively integrates a dedicated, high-performance thermal interface on the circuit board surface. This pad provides an ideal platform for direct mounting of external heat sinks or other cooling devices, achieving a near-integrated heat dissipation path from the chip to the embedded copper block, and then directly to the external heat sink via the vertical conductive post, significantly reducing interface thermal resistance. This structure eliminates the need for multiple thermal interface material layers and complex thermal conductive structures that might be required in traditional methods, simplifying system-level thermal design. Simultaneously, the exposed pad facilitates direct probing during the testing phase, providing convenience for performance verification.

[0013] Preferably, the solid conductive column is a solid copper column formed by an electroplating hole-filling process.

[0014] It was clarified that the solid conductive pillars are manufactured using an electroplating via-filling process to form a solid structure. Solid copper pillars possess higher mechanical strength and better structural integrity, enabling them to withstand more severe thermal cycling stresses without easily being damaged. In terms of thermal conductivity, the solid structure eliminates the thermal resistance associated with hollow or non-metallic fillings, fully utilizing its cross-sectional area and maximizing thermal conductivity. Regarding electrical conductivity, solid copper pillars provide a larger current-carrying cross-sectional area and more uniform current density, which helps reduce resistance and current congestion effects. Electroplating via-filling is a mature technology in modern printed circuit board manufacturing, enabling high aspect ratio microvia filling, ensuring the formed copper pillars are dense and defect-free, and forming a strong bond with the surrounding insulating medium and horizontal substrate, guaranteeing long-term interconnect reliability.

[0015] Preferably, the base portion is made of copper material with a thickness of not less than 0.3 mm.

[0016] This necessitates the use of a thicker copper substrate. Sufficient thickness provides the substrate with greater heat capacity, enabling it to absorb and temporarily store more instantaneous heat, acting as a thermal buffer to prevent a rapid temperature spike in the device. Electrically, the thicker copper provides a larger lateral current-carrying cross-section, significantly improving its ability to conduct large currents in the planar direction and reducing voltage drop. Structurally, the thicker substrate exhibits higher mechanical rigidity, better resisting deformation and stress during subsequent processing and use, maintaining the stability and flatness of the embedded copper block structure, and providing a robust support platform for the components above.

[0017] Preferably, the upper and / or lower surfaces of the base portion of the embedded copper block are provided with positioning grooves, and the ends of the first vertical conductive post and / or the second vertical conductive post are embedded in the positioning grooves and fixedly connected by welding or conductive adhesive.

[0018] By incorporating a positioning groove structure, a mechanical interlocking effect is provided for the connection between the vertical conductive post and the horizontal base. This interlocking structure significantly increases the contact area between the two, reducing not only contact thermal resistance and contact resistance but also enhancing the mechanical strength of the bond through mechanical interlocking. This allows the connection to better withstand the shear stress generated by thermal expansion and contraction, improving the structure's durability in harsh environments. The use of welding or conductive adhesives for fixing further ensures the tightness of the interface and the continuity of electrical and thermal conductivity from both material and process perspectives. This design provides a feasible solution for manufacturing the base and vertical conductive posts separately and then assembling them, increasing manufacturing flexibility to a certain extent.

[0019] Preferably, the circuit board is further provided with a heat sink above the first circuit layer, and the heat sink is thermally connected to the exposed heat dissipation pad through a thermally conductive medium layer.

[0020] This paper describes the integration of an external heatsink into a three-dimensional interconnect structure. The heatsink provides a large heat dissipation surface area, enabling rapid dissipation of heat conducted from the vertical conductive pillars into the surrounding air or other cooling media, making it a necessary component for achieving efficient heat dissipation. A thermally conductive layer connects the heatsink to the top of the vertical conductive pillars, creating a complete and low-thermal-resistance heat dissipation channel from the chip's interior to the external environment. This combined structure fully leverages the thermal conductivity advantages of the embedded copper block three-dimensional interconnect, enabling it to handle continuous high power dissipation and ensuring long-term stable operation of the electronic system within a safe temperature range.

[0021] Preferably, a micro heat pipe or a heat spreader is embedded in the base of the embedded copper block.

[0022] Advanced two-phase heat transfer elements are integrated within the embedded copper block. Miniature heat pipes or vapor chambers possess extremely high equivalent thermal conductivity, enabling rapid diffusion and homogenization of heat from point or line heat sources along the planar direction of the embedded copper block. This internal heat homogenization prevents localized heat accumulation, resulting in a more uniform overall temperature field across the embedded copper block. This allows the entire embedded copper block, especially its connected vertical conductive pillars, to participate more fully in heat dissipation, significantly improving its lateral thermal management efficiency. This is particularly suitable for addressing localized hotspot issues in high-power-density chips.

[0023] The advantages of this utility model compared to the prior art are: This invention relates to an embedded copper circuit board with a vertical interconnect structure. By combining a horizontally positioned base with upwardly and downwardly extending solid conductive pillars, a continuous interconnect path is formed in three dimensions. This integrated structure helps shorten the path of heat transfer from internally generated parts to the heat dissipation interface on the board surface, reducing the number of interfaces traversed during the transfer process, thus positively impacting the reduction of overall thermal resistance. In terms of electrical performance, this structure provides a direct, low-impedance vertical path for current from the inner layer to the surface or bottom layer, which helps improve the transmission efficiency of large currents and may optimize the return path of high-frequency signals.

[0024] Compared to traditional buried copper structures that primarily rely on horizontal heat diffusion and current transfer, this solution enhances thermal management and electrical interconnection capabilities along the board thickness by introducing vertically oriented solid conductive pillars. This collaborative three-dimensional structure provides another feasible design approach for improving the overall performance of the circuit board. Furthermore, this structural form is well-suited to existing circuit board manufacturing processes, such as patterning and electroplating filling, facilitating implementation under current production conditions. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a structural diagram of an embedded copper block circuit board with a vertical interconnection structure, as shown in Embodiment 1 of this utility model.

[0027] Figure 2 This is a structural diagram of an embedded copper block circuit board with a vertical interconnection structure, as shown in Embodiment 2 of this utility model.

[0028] Figure 3 This is a structural diagram of an embedded copper block circuit board with a vertical interconnection structure, as shown in Embodiment 3 of this utility model.

[0029] Figure 4 This is a structural diagram of an embedded copper block circuit board with a vertical interconnection structure, as shown in Embodiment 4 of this utility model.

[0030] Labeling Explanation: 1 First Circuit Layer, 2 Second Circuit Layer, 3 Third Circuit Layer, 4 Fourth Circuit Layer, 5 Embedded Copper Block, 6 Exposed Heat Dissipation Pad, 7 Heat Sink, 8 Heat Spreader, 51 Base, 52 First Vertical Conductive Post, 53 Second Vertical Conductive Post, 54 Positioning Groove. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, 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. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0033] It should be noted that similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. In the description of the embodiments of this application, it should be understood that the terms "upper," "lower," "left," "right," "vertical," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the figures, or the orientation or positional relationship commonly used when the product of this application is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0035] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0036] Example 1 (Basic Structure)

[0037] This embodiment provides an embedded copper block circuit board with a vertical interconnect structure, including a first circuit layer 1, a second circuit layer 2, a third circuit layer 3 and a fourth circuit layer 4 stacked sequentially from top to bottom, and an embedded copper block 5 disposed between the second circuit layer 2 and the third circuit layer 3. The embedded copper block 5 includes a horizontally disposed base portion 51 and a first vertical conductive post 52 extending upward from the base portion 51 and electrically connected to the first circuit layer 1, and / or a second vertical conductive post 53 extending downward from the base portion 51 and electrically connected to the fourth circuit layer 4; both the first vertical conductive post 52 and the second vertical conductive post 53 are solid conductive posts.

[0038] It should be noted that the embedded copper block 5 includes vertical conductive posts extending upwards and / or downwards from the substrate, and the word "and / or" covers three specific implementation methods: Firstly, the embedded copper block 5 comprises only the first vertical conductive post 52 extending upwards. This structure is particularly suitable for scenarios where heat and current are primarily directed to the top of the circuit board, such as when the main heat-generating components are mounted on the first circuit layer 1.

[0039] Secondly, the embedded copper block 5 only includes the downward-extending second vertical conductive post 53. This structure is suitable for scenarios where heat and current need to be directed to the bottom of the circuit board or the system chassis for heat dissipation.

[0040] Thirdly, the embedded copper block 5 includes both the first vertical conductive post 52 and the second vertical conductive post 53. This is a preferred solution for bidirectional interconnection, enabling the most efficient bidirectional heat dissipation and current transmission, significantly improving the heat dissipation capacity and electrical interconnection performance of the circuit board in the thickness direction, as detailed below.

[0041] By integrating vertically extending solid conductive pillars onto the horizontal substrate 51, a three-dimensional interconnect network extending through the thickness of the circuit board is constructed. The horizontal substrate 51 is primarily responsible for dissipating heat and conducting large currents in the planar direction, while the vertical conductive pillars establish a direct, low-resistance path from the core of the circuit board to the surface and even the bottom layer. This three-dimensional structure significantly shortens the distance from the heat source to the heat dissipation endpoint, reduces the overall thermal resistance, and allows heat accumulated at the embedded copper block 5 to be quickly and efficiently conducted to the outer surface of the circuit board and dissipated into the environment through possible additional heat dissipation components, thereby effectively controlling the operating temperature of high-power devices. In terms of electrical performance, this structure provides extremely low DC impedance and minimal loop inductance, meeting the requirements of high current transmission and improving the return path of high-frequency signals, thus enhancing signal integrity. Compared with traditional circuit boards that only have a horizontal embedded copper structure, this three-dimensional interconnect method solves the problems of interlayer thermal isolation and poor electrical connection, achieving a synergistic improvement in heat dissipation and current carrying capacity. Furthermore, this structure integrates the main vertical interconnect functions into the embedded copper block 5 body without taking up too much additional wiring space, which is conducive to achieving high-density integration and miniaturization of electronic devices. At the same time, its structural form has good compatibility with existing mature circuit board manufacturing processes, such as electroplating and via filling, making it easy to implement and promote.

[0042] The following description of this embodiment will take the third structure that simultaneously includes bidirectional vertical conductive pillars as an example, but this should not be construed as limiting the scope of this utility model.

[0043] In this embodiment, the upper end face of the first vertical conductive post 52 is directly electrically and thermally connected to the lower surface of the first circuit layer 1.

[0044] The first vertical conductive post 52 and the first circuit layer 1 are in direct physical contact. This direct electrical and thermal connection interface avoids the additional thermal resistance and contact resistance that may be introduced by using intermediate adhesive materials, creating a highly efficient channel for heat transfer from the vertical conductive post to the first circuit layer 1 and for current flow. It ensures that the performance of thermal management and electrical connection is not compromised by the limitations of the interface material, resulting in more direct and significant heat dissipation and conductivity. At the same time, this direct electrical and thermal connection structure simplifies the alignment and connection steps in the manufacturing process, helps improve production yield and reduce process complexity, and structurally guarantees the reliability and consistency of the interconnection.

[0045] In this embodiment, the lower end face of the second vertical conductive post 53 is directly electrically and thermally connected to the upper surface of the fourth circuit layer 4.

[0046] By establishing a direct electrical and thermal connection between the second vertical conductive post 53 and the fourth circuit layer 4, an efficient heat and current outlet is also created at the bottom of the circuit board. This design allows heat from the embedded copper block 5 to be transferred not only upwards to the first circuit layer 1 but also simultaneously downwards to the fourth circuit layer 4, achieving a bidirectional heat dissipation path and enhancing the redundancy and overall heat dissipation capacity of the heat dissipation system. In terms of electrical connectivity, it provides another low-impedance vertical interconnect channel, helping to further reduce the impedance of the entire power distribution network and providing more optional, high-quality return paths for signals, thereby improving the stability and reliability of the circuit board under complex operating conditions. The bidirectional vertical interconnect structure results in a more balanced heat management and current distribution.

[0047] In this embodiment, the solid conductive pillar is a solid copper pillar formed by an electroplating hole-filling process.

[0048] It is clarified that the solid conductive pillars are manufactured using an electroplating via-filling process to form a solid structure. Solid copper pillars possess higher mechanical strength and better structural integrity, enabling them to withstand more severe thermal cycling stresses without easily being damaged. In terms of thermal conductivity, the solid structure eliminates the thermal resistance associated with hollow or non-metallic fillings, fully utilizing its cross-sectional area and maximizing thermal conductivity. Regarding electrical conductivity, solid copper pillars provide a larger current-carrying cross-sectional area and more uniform current density, which helps reduce resistance and current congestion effects. Electroplating via-filling is a mature technology in modern printed circuit board manufacturing, enabling high aspect ratio microvia filling, ensuring the formed copper pillars are dense and defect-free, and forming a strong bond with the surrounding insulating medium and horizontal substrate 51, guaranteeing long-term interconnect reliability.

[0049] In this embodiment, the base portion 51 is made of copper material with a thickness of not less than 0.3 mm.

[0050] The substrate 51 is constructed using a thicker copper material. Sufficient thickness provides the substrate 51 with a greater heat capacity, enabling it to absorb and temporarily store more instantaneous heat, acting as a thermal buffer to prevent a rapid temperature spike in the device. Electrically, the thicker copper provides a larger lateral current-carrying cross-sectional area, significantly improving its ability to conduct large currents in the planar direction and reducing voltage drop. Structurally, the thicker substrate 51 has higher mechanical rigidity, better resisting deformation and stress during subsequent processing and use, maintaining the stability and flatness of the embedded copper block 5 structure, and providing a stable support platform for the components above it.

[0051] In summary, this embodiment constructs an efficient and reliable three-dimensional interconnect infrastructure, laying a solid core foundation for subsequent performance optimization and functional expansion.

[0052] Example 2 (Mechanical Connection Structure)

[0053] This embodiment is a further optimization based on Embodiment 1, focusing on improving the connection reliability between the vertical conductive post and the horizontal base. Its main improvements are: In this embodiment, the upper and / or lower surfaces of the base portion 51 of the embedded copper block 5 are provided with positioning grooves 54, and the ends of the first vertical conductive post 52 and / or the second vertical conductive post 53 are embedded in the positioning grooves 54 and fixedly connected by welding or conductive adhesive.

[0054] By incorporating the positioning groove 54 structure, a mechanical interlocking effect is provided for the connection between the vertical conductive post and the horizontal base 51. This interlocking structure significantly increases the contact area between the two, not only reducing contact thermal resistance and contact resistance, but also enhancing the mechanical strength of the bond through mechanical interlocking. This allows the connection to better withstand the shear stress generated by thermal expansion and contraction, improving the durability of the structure in harsh environments. The use of welding or conductive adhesive for fixing further ensures the tightness of the interface and the continuity of electrical and thermal conductivity from both material and process perspectives. This design provides a feasible solution for separately manufacturing the base 51 and the vertical conductive post before assembly, increasing manufacturing flexibility to a certain extent.

[0055] Therefore, this embodiment significantly enhances the mechanical stability and long-term service reliability of the three-dimensional interconnect structure by introducing a mechanical interlocking design with a positioning groove 54.

[0056] Example 3 (Integrated Heatsink Structure)

[0057] This embodiment is a further optimization of embodiment 1 or 2, aiming to construct an efficient heat dissipation path from the chip to the external environment. Its main improvements are: In this embodiment, the first vertical conductive post 52 extends upward to the upper surface of the first circuit layer 1 and forms an exposed heat dissipation pad 6.

[0058] Extending the first vertical conductive post 52 directly to the outermost layer of the circuit board and forming an exposed pad effectively integrates a dedicated, high-performance heat dissipation interface on the circuit board surface. This pad provides an ideal platform for direct mounting of external heat sinks or other cooling devices, achieving a near-integrated heat dissipation path from the chip to the embedded copper block 5, and then directly to the external heat sink via the vertical conductive post, significantly reducing interface thermal resistance. This structure eliminates the need for multiple thermal interface material layers and complex thermal conductive structures that might be required in traditional methods, simplifying system-level heat dissipation design. Simultaneously, the exposed pad facilitates direct probing during the testing phase, providing convenience for performance verification.

[0059] In this embodiment, a heat sink 7 is also provided on the circuit board above the first circuit layer 1. The heat sink 7 is thermally connected to the exposed heat dissipation pad 6 through a thermally conductive medium layer.

[0060] The integration of an external heatsink 7 into a three-dimensional interconnect structure is described. Heatsink 7 provides a large heat dissipation surface area, enabling rapid dissipation of heat conducted from the vertical conductive pillars into the surrounding air or other cooling media, making it a necessary component for achieving efficient heat dissipation. A thermally conductive medium layer thermally connects heatsink 7 to the top of the vertical conductive pillars, constructing a complete and low-thermal-resistance heat dissipation channel from the chip's interior to the external environment. This combined structure fully leverages the thermal conductivity advantages of the embedded copper block 5's three-dimensional interconnect, capable of handling continuous high power dissipation and ensuring long-term stable operation of the electronic system within a safe temperature range.

[0061] In summary, this embodiment combines the thermal conductivity advantages of internal three-dimensional interconnection with the external high-efficiency heat dissipation capability by forming an exposed heat dissipation pad 6 and integrating a heat sink 7, thereby achieving excellent system-level thermal management performance.

[0062] Example 4 (Embedded Phase Change Heat Dissipation Structure)

[0063] This embodiment is a further optimization of embodiment 1, 2, or 3, with the core focus on improving the lateral temperature uniformity of the embedded copper block to address the challenge of localized high heat flux density. Its main improvements are: In this embodiment, a micro heat pipe or a heat spreader 8 is embedded in the base portion 51 of the embedded copper block 5.

[0064] More advanced two-phase heat transfer elements are integrated within the embedded copper block 5. The micro heat pipes or vapor chamber 8 possess extremely high equivalent thermal conductivity, enabling them to rapidly diffuse and homogenize heat from point or line heat sources along the planar direction of the embedded copper block 5. This internal heat homogenization prevents localized heat accumulation, resulting in a more uniform overall temperature field for the embedded copper block 5. This allows the entire embedded copper block 5, especially its connected vertical conductive pillars, to participate more fully in heat dissipation, significantly improving its lateral thermal management efficiency. This is particularly suitable for addressing localized hotspot issues in high-power-density chips.

[0065] The innovation of this embodiment lies in integrating two-phase flow heat dissipation technology into the copper block substrate, which fundamentally enhances its lateral heat diffusion capability and provides an efficient internal solution for eliminating local hot spots. It is a powerful supplement to the three-dimensional interconnected heat dissipation system.

[0066] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An embedded copper block circuit board with a vertical interconnect structure, comprising a first circuit layer (1), a second circuit layer (2), a third circuit layer (3), and a fourth circuit layer (4) stacked sequentially from top to bottom, and an embedded copper block (5) disposed between the second circuit layer (2) and the third circuit layer (3), characterized in that, The embedded copper block (5) includes a horizontally arranged base portion (51), a first vertical conductive post (52) extending upward from the base portion (51) and electrically connected to the first circuit layer (1), and / or a second vertical conductive post (53) extending downward from the base portion (51) and electrically connected to the fourth circuit layer (4); the first vertical conductive post (52) and the second vertical conductive post (53) are both solid conductive posts.

2. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The upper end face of the first vertical conductive post (52) is directly electrically and thermally connected to the lower surface of the first circuit layer (1).

3. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The lower end face of the second vertical conductive post (53) is directly electrically and thermally connected to the upper surface of the fourth circuit layer (4).

4. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The first vertical conductive post (52) extends upward to the upper surface of the first circuit layer (1) and forms an exposed heat dissipation pad (6).

5. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The solid conductive column is a solid copper column formed by an electroplating hole-filling process.

6. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The base part (51) is made of copper material with a thickness of not less than 0.3 mm.

7. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The upper and / or lower surfaces of the base portion (51) of the embedded copper block (5) are provided with positioning grooves (54), and the first vertical conductive post (52) and / or the second vertical conductive post (53) are connected to the positioning grooves (54).

8. The embedded copper block circuit board with a vertical interconnect structure according to claim 7, characterized in that, The ends of the first vertical conductive post (52) and / or the second vertical conductive post (53) are embedded in the positioning groove (54) and fixedly connected by welding or conductive adhesive.

9. The embedded copper block circuit board with a vertical interconnect structure according to claim 4, characterized in that, The circuit board is further provided with a heat sink (7) above the first circuit layer (1), and the heat sink (7) is thermally connected to the exposed heat dissipation pad (6) through a thermally conductive medium layer.

10. The embedded copper block circuit board with a vertical interconnect structure according to claim 1, characterized in that, The embedded copper block (5) has a micro heat pipe or a heat spreader (8) embedded in its base part (51).

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