A copper block printed board with high heat dissipation and manufacturing method thereof

Abstract

The application belongs to the technical field of printed board manufacturing, and particularly discloses a copper block printed board with high heat dissipation efficiency and a manufacturing method, which comprises a printed board body and a copper block embedded in the printed board body; the copper block comprises a first copper block and a second copper block arranged along the thickness direction of the printed board body; and the first copper block is arranged in close contact with the second copper block. The application utilizes the continuous structure of the copper block to improve the heat dissipation efficiency, simplifies the production process, reduces the processing difficulty in a step-by-step forming mode, and is suitable for automatic batch production.

Description

Technical Field

[0001] This invention belongs to the field of printed circuit board manufacturing technology, specifically relating to a high-efficiency heat dissipation copper block printed circuit board and its manufacturing method. Background Technology

[0002] Printed Circuit Boards (PCBs), also known as printed circuit boards, are essential electronic components. They serve as the support for electronic devices and the carrier for interconnecting these devices, finding widespread application in daily life. As electronic devices evolve towards higher frequencies, higher speeds, and higher power, the heat dissipation performance and signal transmission efficiency of traditional PCBs face severe challenges. In particular, the large amount of heat generated by high-power electronic devices during operation, if not dissipated effectively and promptly, will lead to performance degradation or even device failure. Embedded copper technology, by embedding or embedding copper blocks within the PCB, enhances its electrical and thermal properties, significantly improving heat dissipation, reducing impedance, and increasing mechanical strength. This technology is widely used in communication base stations, automotive electronics, aerospace, and other fields.

[0003] However, current copper embedding technology in the industry primarily relies on flowing resin in a prepreg to fill the interface, followed by resin curing via lamination to achieve bonding. This method has significant process drawbacks: First, pressure loss and insufficient resin application are prone to occur during the curing process, leading to insufficient adhesion; second, the resin material has poor heat resistance and is susceptible to performance degradation at high temperatures; third, due to process limitations, the insulation performance between the copper embedding structure and other circuits is difficult to guarantee, requiring a large safety distance, which not only limits wiring density but also increases design complexity. Furthermore, existing copper embedding processes are complex, making it difficult to ensure production consistency and unsuitable for mass production needs. These problems severely restrict the performance improvement and reliability assurance of high-power electronic devices. Summary of the Invention

[0004] The purpose of this invention is to provide a copper block printed circuit board with high-efficiency heat dissipation and a manufacturing method thereof. The continuous structure of the copper block improves heat dissipation efficiency, has the advantages of structural stability and excellent heat dissipation performance, and reduces the processing difficulty, making it suitable for automated mass production.

[0005] To achieve the above objectives, the present invention employs the following technical solution: According to a first aspect of the present invention, a high-efficiency heat dissipation copper block printed circuit board is provided, comprising: The printed circuit board body and the copper block embedded inside the printed circuit board body; The copper block includes a first copper block and a second copper block disposed along the thickness direction of the printed circuit board body; the first copper block and the second copper block are attached to each other.

[0006] The above technical solution solves the problem of insufficient bonding strength caused by the resin filling process, forming a stable interface through direct metal bonding; it eliminates the defect of poor resin heat resistance, improving heat dissipation efficiency through the continuous copper block structure; it simplifies the production process, reducing processing difficulty through step-by-step molding, and is suitable for automated mass production. Setting copper blocks within the printed circuit board body provides stronger electrical and thermal performance compared to traditional fiberglass cloth PCB copper foil, meeting the high heat dissipation requirements of printed circuit boards. The first and second copper blocks are not formed in one piece, resulting in strong compressive strength and good heat dissipation performance. This avoids thickness differences or shape tolerances between the copper blocks and the printed circuit board body, essentially eliminating stress issues caused by different materials.

[0007] According to one embodiment of the present invention, the copper block is disposed through the printed circuit board body.

[0008] Therefore, a single, continuous copper block is incorporated into the printed circuit board body. The flatness of the copper block is easily controlled, and its heat dissipation capacity is strong. The copper block forms a complete, low-impedance path when conducting electricity, reducing energy loss during signal transmission. The physical penetration of the copper block into the substrate replaces resin bonding, maintaining structural stability even under conditions of different coefficients of thermal expansion.

[0009] According to one embodiment of the present invention, the first copper block and the second copper block are formed by electroplating or electrodeposition.

[0010] When forming copper blocks within the printed circuit board (PCB), electroplating uses an electric current to reduce and deposit copper ions in the electrolyte onto the substrate surface, forming a copper layer atomically bonded to the substrate. Electrodeposition, on the other hand, uses a chemical reaction to autocatalytically reduce copper ions in the solution onto the substrate surface, forming a non-porous copper layer. Both processes replace traditional resin filling with direct metal deposition, eliminating the need for the high temperature and pressure conditions of lamination processes and avoiding the reduced adhesion caused by insufficient resin flow. The continuous deposition process of the copper layer on the substrate surface allows for precise control of thickness and shape, eliminating interfacial stress caused by resin curing shrinkage in traditional processes.

[0011] Therefore, there is no need to place copper blocks during the lamination process. The copper blocks can form a strong bond with the substrate without lamination. Electroplating or electrodeposition can reduce the thickness difference and shape tolerance between the resulting copper blocks and the printed circuit board body, thereby improving the matching effect of the printed circuit board. The electroplating or electrodeposition process is simple and can not only ensure the bonding force between the copper blocks and the printed circuit board body, but also avoid defects such as pressure loss and insufficient adhesive during processing. Furthermore, it can reduce the probability of insufficient withstand voltage and insulation.

[0012] According to a second aspect of the present invention, a method for manufacturing a high-efficiency heat-dissipating copper block printed circuit board is provided, comprising the following steps: The first side of the printed circuit board is subjected to a router blinding process to obtain the first blind slot; The printed circuit board body is subjected to copper plating to obtain the first copper block, and then the first copper block is thickened to fill the first blind slot. The second side of the printed circuit board body is subjected to a router blinding process to obtain a second blind slot; the bottom of the second blind slot is in contact with the first copper block; The printed circuit board body is subjected to copper plating again to obtain a second copper block. The second copper block is then thickened to fill the second blind slot.

[0013] The above technical solution solves the problems of poor adhesion and heat resistance defects caused by insufficient resin filling in traditional copper-embedded boards. Direct bonding between the copper block and the substrate improves heat dissipation efficiency, and the step-by-step molding process avoids uneven copper deposition in deep blind trenches. The copper block contact structure formed by two round-blind machining processes enhances current conductivity, and the copper body formed by chemical deposition has a higher density than that of the lamination process, improving mechanical stability. This method achieves efficient fabrication of copper-embedded printed circuit boards through process optimization, and is suitable for the heat dissipation requirements of high-frequency, high-power electronic devices.

[0014] According to one embodiment of the present invention, the depth of the first blind slot is 55%-60% of the thickness of the printed circuit board body.

[0015] According to one embodiment of the present invention, the step of thickening the first copper block includes: The printed circuit board body with the first copper block after copper plating is fully electroplated. The printed circuit board body with full electroplating is subjected to patterned dry film treatment; The printed circuit board body is subjected to pattern dry film treatment, followed by pattern electroplating and film removal treatment to achieve the thickening of the first copper block.

[0016] Furthermore, after the film is removed, the printed circuit board body can be subjected to electroplating grinding treatment to obtain a first copper block with a smooth surface.

[0017] Furthermore, when performing full-board electroplating on the printed circuit board, the electroplating thickness is 5μm-8μm.

[0018] Full-board electroplating establishes a continuous conductive layer on the surface of the printed circuit board where the first copper block has been formed, providing a stable substrate for subsequent pattern processing. Pattern dry film processing precisely defines the boundaries of the circuit pattern through exposure and development, avoiding interface defects caused by resin filling in traditional processes. Pattern electroplating thickens the copper layer within the defined area, forming a conductive structure tightly bonded to the substrate. After film removal, grinding removes residual dry film and electroplating burrs, achieving a smooth surface for the first copper block and reducing stress concentration during subsequent router blinding. The synergistic effect of staged electroplating and grinding strengthens the bond between the copper block and the substrate while simplifying the complex process of traditional multilayer lamination.

[0019] According to one embodiment of the present invention, the step of performing patterned dry film treatment on the fully electroplated printed circuit board body includes: Photosensitive dry film is applied to the copper foil surfaces of the first and second sides of the printed circuit board after full electroplating, and then exposed and developed. During the development process, a dilute alkaline solution is used to dissolve the unexposed photosensitive dry film.

[0020] According to one embodiment of the present invention, the dilute alkaline solution is a sodium carbonate solution or a potassium carbonate solution with a molar concentration of 0.8%-1.2%.

[0021] After a photosensitive dry film is applied to the copper foil surface, the pre-designed circuit pattern area is irradiated with ultraviolet light using an exposure device, causing the dry film in that area to undergo a photopolymerization reaction and form a cured structure. During the development process, a dilute alkaline solution is sprayed onto the board surface. The dry film in the unexposed areas, which is not cross-linked, is dissolved, thus exposing the copper layer that needs to be etched. Due to the weak corrosiveness of the dilute alkaline solution, the edges of the cured dry film remain intact, avoiding circuit gaps or residual adhesive problems caused by over-development.

[0022] According to one embodiment of the present invention, the step of thickening the second copper block includes: The printed circuit board body, which has undergone copper plating treatment and has a first copper block and a second copper block, is then fully electroplated again. The printed circuit board body with full electroplating is subjected to patterned dry film treatment; The printed circuit board body is subjected to pattern dry film treatment, followed by pattern electroplating and film removal treatment to achieve the thickening of the second copper block.

[0023] Furthermore, the printed circuit board body after film removal is subjected to electroplating and grinding treatment to obtain a second copper block with a smooth surface.

[0024] Furthermore, after the first copper block thickening treatment, the first surface of the printed circuit board body can be subjected to electroplating site grinding treatment to obtain a flat first copper block. Then, after the second copper block thickening treatment, the second surface of the printed circuit board body can be subjected to electroplating site grinding treatment again to obtain a flat second copper block. Alternatively, after the second copper block thickening treatment, the first and second surfaces of the printed circuit board body can be subjected to electroplating site grinding treatment to obtain a flat first copper block and a flat second copper block.

[0025] According to one embodiment of the present invention, after obtaining the first copper block and the second copper block, the method further includes the following steps: The printed circuit board body undergoes surface copper reduction treatment, followed by a third copper plating treatment and pattern dry film treatment. Then, it is subjected to pattern electroplating with copper and tin and film stripping etching to obtain a copper block printed circuit board.

[0026] After the first and second copper blocks are formed, the surface copper reduction treatment removes redundant copper layers, resulting in a uniform and smooth substrate surface that provides a uniform substrate environment for the third copper plating process. The third copper plating process forms a continuous metal layer on the copper-reduced substrate surface, filling any potential micro-defects and enhancing the mechanical bonding strength between the copper blocks and the substrate.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects: This invention provides a high-efficiency heat dissipation copper block printed circuit board and its manufacturing method. The first and second copper blocks are embedded into the printed circuit board body through step-forming, and the copper blocks and the printed circuit board are seamlessly combined by electroplating process. This avoids the defects of traditional resin filling process and has the advantages of stable structure, excellent heat dissipation performance and suitability for mass production. Attached Figure Description

[0028] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A partial photograph of the high-efficiency heat dissipation copper block printed circuit board of Example 1, in which the copper block is embedded; Figure 2 This is a schematic diagram of obtaining the first blind slot by performing a router blinding process on the printed circuit board body in Example 2; Figure 3 This is a schematic diagram of the copper plating process performed on the printed circuit board body in Example 2 to obtain the first copper block; Figure 4 This is a schematic diagram of obtaining the second blind slot by performing a router blinding process on the printed circuit board body in Example 2; Figure 5 This is a schematic diagram of the copper plating process performed on the printed circuit board body in Example 2 to obtain a second copper block.

[0029] Reference numerals in the attached drawings: 1. Printed circuit board body; 2. First blind slot; 3. First copper block; 4. Second blind slot; 5. Second copper block. Detailed Implementation

[0030] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0031] The following detailed description is exemplary and intended to provide further detailed explanation of the invention. Unless otherwise specified, all technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this invention is for describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention.

[0032] Example 1 This embodiment provides a high-efficiency heat dissipation copper block printed circuit board, see [link / reference]. Figure 1 The copper block printed circuit board includes a printed circuit board body 1 and a copper block embedded therein. The copper block consists of a first copper block 3 and a second copper block 5 arranged along the thickness direction. The two are bonded together and formed sequentially. The first copper block 3 and the second copper block 5 are formed by electroplating or electrodeposition, and the side copper block formed by the first copper block 3 and the second copper block 5 is integrally disposed through the printed circuit board body 1.

[0033] The printed circuit board body 1 refers to the substrate layer that carries the circuit pattern. Specifically, it can be implemented using an FR-4 epoxy resin substrate or a polyimide substrate, serving as the basic carrier for the embedded copper blocks. The first copper block 3 provides a supporting interface for the formation of the second copper block 5. The first copper block 3 and the second copper block 5 together form an embedded structure within the printed circuit board body 1, completely penetrating along the thickness direction of the printed circuit board body 1 to form a continuous heat dissipation channel. The sequential forming of the first copper block 3 and the second copper block 5 refers to their independent processing in stages. This can be achieved through two separate processes of router blind slots and copper plating, avoiding bonding defects caused by single-stage pressing. This step-by-step forming method allows for independent control of the processing accuracy of the first copper block 3 and the second copper block 5, avoiding stress concentration problems caused by overall pressing. Thus, by directly combining the first copper block 3 and the second copper block 5 to form a continuous result, the risk of interface cracking caused by differences in the coefficients of thermal expansion of the printed circuit board body 1 is eliminated. Traditional printed circuit boards require the pre-formation of copper blocks before lamination, and the bonding between the copper blocks and the substrate depends on the adhesive force of the resin. However, the copper block printed circuit board provided in this embodiment achieves molecular-level bonding between the copper layer and the substrate by setting the first copper block 3 and the second copper block 5 in the front and back, which significantly improves the bonding strength and heat resistance.

[0034] Example 2 The method for manufacturing the copper block printed circuit board of Embodiment 1 above includes the following steps: The first surface of the printed circuit board body 1 is subjected to a router blinding process to obtain the first blind slot 2, see [reference]. Figure 2 ; The printed circuit board body 1 undergoes copper plating to obtain the first copper block 3. The first copper block 3 is then thickened to fill the first blind slot 2. (See [reference]). Figure 3 ; The second side of the printed circuit board body 1 is subjected to router blinding to obtain the second blind slot 4, see [reference]. Figure 4 The bottom of the second blind slot 4 is one face of the first copper block 3; The printed circuit board body 1 is subjected to copper plating again to obtain the second copper block 5. The second copper block 5 is then thickened to fill the second blind slot 4. See [link to relevant documentation]. Figure 5 .

[0035] During the router blinding process, a CNC machine tool can be used to control the depth of the router cutter, forming a space in the printed circuit board body 1 for embedding the first copper block 3 and / or the second copper block 5, namely the first blind slot 2 and / or the second blind slot 4. Through copper plating, a dense copper body is formed in the first blind slot 2 and the second blind slot 4. The bottoms of the first blind slot 2 and the second blind slot 4 are connected, meaning that the first blind slot 2 and the second blind slot 4 formed by router blinding the first and second surfaces of the printed circuit board body 1 have an overlapping area in the thickness direction. This can be achieved by precisely controlling the cutting depth of the router cutter twice, ensuring that the two copper blocks form a continuous conductive path.

[0036] Using the above method, blind slots and copper plating are performed in stages on both sides of the printed circuit board body 1. First, an embedded first copper block 3 is formed on the first side. Then, a second blind slot 4 that contacts the first copper block 3 is processed on the second side, and a second copper block 5 is deposited. The two copper blocks form a direct metal connection in the thickness direction through the bottom contact of the slots, avoiding the thermal resistance caused by the resin filling layer in the traditional process. The step-by-step copper plating process allows each copper block to be formed independently, effectively controlling the matching relationship between the blind slot depth and the copper plating thickness, and preventing the problem of uneven copper plating caused by deep blind slots in a single forming.

[0037] The copper block contact structure formed by two round-blind machining processes enhances current conductivity, and the copper body formed by chemical deposition has a higher density than that formed by lamination, thus improving mechanical stability. This method achieves efficient fabrication of copper block printed circuit boards through process optimization and is suitable for the heat dissipation requirements of high-frequency, high-power electronic devices.

[0038] Furthermore, the depth of the first blind groove 2 is 55%-60% of the thickness of the printed circuit board body 1. After processing the first blind groove 2 with a depth within this range on the first side of the printed circuit board body 1, a copper plating process is performed to form a first copper block 3 with a continuous metal structure. In this way, limiting the depth of the first blind groove 2 ensures that the copper layer fully fills the groove during the copper plating process, while reserving sufficient substrate support for the processing of the second blind groove 4. This avoids both insufficient contact area between the copper layer and the substrate due to the first blind groove 2 being too shallow, and excessively deep first blind groove 2 causing the remaining substrate to be too thin, thus reducing structural stability. Subsequently, when processing the second blind groove 4 on the second side, the remaining substrate thickness is sufficient to support the formation of the second copper block 5, allowing the copper blocks formed by the two copper plating processes to form a tight overlap in the thickness direction, reducing the obstruction of heat conduction by the interface gaps.

[0039] It should be noted that the steps for thickening the first copper block 3 include: The printed circuit board body 1, which has undergone copper plating treatment and has the first copper block 3, is subjected to full-board electroplating. The printed circuit board body 1, which is fully electroplated, is subjected to patterned dry film treatment. The printed circuit board body 1 is subjected to pattern dry film treatment, followed by pattern electroplating and film removal treatment to achieve the thickening of the first copper block 3.

[0040] Full-board electroplating refers to covering the entire surface of the printed circuit board body 1 with a conductive copper layer, which can be achieved using an acidic copper sulfate electroplating solution. This step provides a uniform conductive substrate for subsequent pattern processing. Pattern dry film processing refers to forming circuit patterns on the copper layer surface using photosensitive materials, which can be achieved using ultraviolet exposure combined with dilute alkaline development. This step precisely defines the electroplating area and avoids the resin filling defects of traditional lamination processes. Pattern electroplating refers to selectively thickening the copper layer in the developed area. In this embodiment, pattern electroplating is used to thicken the copper layer in the area of ​​the first blind trench 2. This can be achieved using pulse electroplating technology, which enhances local conductivity and forms structural support. Electroplating site grinding treatment refers to physically polishing the electroplating area, which can be achieved using an alumina grinding wheel. This step eliminates burrs at the electroplating edges and improves surface smoothness.

[0041] Furthermore, after the film is removed, the first surface of the printed circuit board body 1 after the film is removed can be subjected to electroplating and grinding treatment to obtain a first copper block 3 with a flat surface.

[0042] Furthermore, when performing full-board electroplating on the printed circuit board body 1, the electroplating thickness is 5μm-8μm.

[0043] The steps for pattern dry film treatment of the printed circuit board body 1 with full-board electroplating include: After electroplating, the copper foil surfaces on the first and second sides of the printed circuit board are covered with photosensitive dry film and exposed to light, followed by development. During development, a dilute alkaline solution is used to dissolve the unexposed photosensitive dry film. The dilute alkaline solution is a sodium carbonate or potassium carbonate solution with a molar concentration of 0.8%-1.2%.

[0044] Photosensitive dry film refers to a photosensitive polymer material, specifically a UV-curable dry film. It forms a resist layer through a cross-linking reaction in the exposed areas, while the unexposed areas remain soluble. This material acts as a mask layer during development, protecting the copper foil surface from subsequent etching. The dilute alkaline solution is a weakly alkaline solution, typically an aqueous solution of sodium carbonate or potassium carbonate. It dissolves any uncured dry film residue, preventing excessive corrosion of the copper layer and substrate by strong acids or alkalis. The solution concentration is controlled within a specific range, such as a molar concentration of 0.8%–1.2%, to balance development efficiency with material protection requirements.

[0045] After a photosensitive dry film is applied to the copper foil surface, the pre-designed circuit pattern area is irradiated with ultraviolet light using an exposure device, causing the dry film in that area to undergo a photopolymerization reaction and form a cured structure. During the development process, a dilute alkaline solution is sprayed onto the board surface. The dry film in the unexposed areas, which is not cross-linked, is dissolved, thus exposing the copper layer that needs to be etched. Due to the weak corrosiveness of the dilute alkaline solution, the edges of the cured dry film remain intact, avoiding circuit gaps or residual adhesive problems caused by over-development.

[0046] Further, the step of thickening the second copper block 5 includes: The printed circuit board body 1, which has undergone copper plating treatment and has the first copper block 3 and the second copper block 5, is then subjected to full-board electroplating again. The printed circuit board body 1, which is fully electroplated, is subjected to patterned dry film treatment. The printed circuit board body 1 is subjected to pattern dry film treatment, followed by pattern electroplating and film removal treatment to achieve the thickening of the second copper block 5.

[0047] In this embodiment, the copper layer thickness in the area of ​​the second blind trench 4 is achieved by pattern electroplating in this step.

[0048] The second surface of the printed circuit board body 1 after the film is removed is subjected to electroplating and grinding treatment to obtain a second copper block 5 with a smooth surface.

[0049] After obtaining the thickened first copper block 3 and second copper block 5, the following steps are also included: The printed circuit board body 1 undergoes a surface copper reduction treatment, followed by a third copper plating treatment and a pattern dry film treatment. Then, it undergoes pattern electroplating with copper and tin and film stripping etching to obtain a copper block printed circuit board.

[0050] Specifically, the current density for full-plate electroplating can be controlled within the range of 2-3 A / dm², the plating time can be controlled within 25-35 minutes, and the plating thickness can be 5-8 μm. The thickness of the photosensitive material used in the patterned dry film processing can be 15-25 μm, and the exposure energy can be set to 80-120 mJ / cm². The temperature of the alkaline solution used in the film stripping process can be maintained at 40-50℃, and the processing time can be 3-5 minutes. The polishing wheel speed used in the grinding process can be adjusted to 200-300 rpm, and the grinding pressure can be set to 0.1-0.3 MPa.

[0051] After the first copper block 3 and the second copper block 5 are formed, the surface copper reduction treatment removes the redundant copper layer on the surface, making the substrate surface uniform and flat, providing a uniform substrate environment for the third copper plating treatment. The third copper plating treatment forms a continuous metal layer on the surface of the copper-reduced substrate, filling any possible micro-defects and enhancing the mechanical bonding strength between the copper block and the substrate.

[0052] Traditional copper inlay processes rely on prepreg resin to fill the interface, which easily leads to problems such as insufficient adhesive and poor heat resistance. This solution replaces resin bonding by forming a continuous metal layer through full-board electroplating, combined with pattern processing to precisely control the circuit area and eliminate interface filling defects. Existing technologies require multiple pressing steps and are limited by the shape of the copper block. This solution uses step-by-step electroplating and grinding to achieve integrated molding of the copper block and the substrate, reducing process complexity.

[0053] In this embodiment, the printed circuit board body 1 is made of FR-4 material. Before the router blinding process, the FR-4 needs to undergo processes such as cutting, internal bonding, lamination, and target punching. In other embodiments, the printed circuit board body 1 can also be a double-layer board, omitting the cutting, internal bonding, lamination, and target punching processes. The specific process flow of this embodiment is as follows: The first side of FR-4 is router-blinded to obtain a first blind groove 2. The first blind groove 2 is then subjected to copper plating to obtain a first copper block 3 located inside the first blind groove 2. The FR-4 is then subjected to full-board electroplating with a plating thickness of 5-8 μm. Next, FR-4 undergoes double-sided lamination, followed by development and pattern electroplating to thicken the first copper block 3, filling the first blind groove 2. After film removal, FR-4 is ground to the electroplating area. Then, the second side of FR-4 is router-blinded to the copper plating layer, i.e., the first copper block 3, to obtain a second blind groove 4. The second blind groove is then subjected to copper plating to obtain a second copper block 5 located inside the second blind groove 4. FR-4 undergoes a second full-board electroplating with a plating thickness of 5-8 μm. Then, FR-4 undergoes a second double-sided lamination, followed by a second development and pattern electroplating to thicken the second copper block 5, filling the second blind groove 4. After film removal, FR-4 is ground to the electroplating area. Afterwards, the FR-4 undergoes a copper reduction process, reducing the copper thickness by 10-15μm. Following drilling through holes and copper plating, it undergoes a third normal pattern dry film treatment, followed by copper-tin plating. Then, it is processed with film removal etching, AOI, solder mask text, etc. After surface treatment, shaping, and cleaning, it is tested, inspected for appearance, packaged, and put into storage.

[0054] Through the above technical solution, this application solves the problem of insufficient bonding strength caused by resin filling in traditional copper-embedded boards, and directly forms a reliable connection between the copper block and the circuit through metal deposition and patterning processes. It improves the withstand voltage performance between copper-embedded and non-copper-embedded areas, allowing for smaller spacing between different circuit networks. The production process is optimized, converting multiple lamination processes into continuous copper plating and electroplating steps, suitable for large-scale mass production. While maintaining high heat dissipation performance, tin plating enhances surface oxidation resistance, extending the service life of the printed circuit board in high-temperature and high-humidity environments.

[0055] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A high-efficiency heat dissipation copper block printed circuit board, characterized in that, Includes a printed circuit board body (1) and a copper block embedded inside the printed circuit board body (1); The copper block is disposed through the printed circuit board body (1) and includes a first copper block (3) and a second copper block (5) disposed along the thickness direction of the printed circuit board body (1); the first copper block (3) and the second copper block (5) are attached to each other; The printed circuit board body (1) has a first blind groove (2) extending inward from a first surface and a second blind groove (4) extending inward from a second surface; the first copper block (3) is formed by plating copper on the first blind groove (2) and then thickening and filling the first blind groove (2); the second blind groove (4) is formed by drilling copper from the second surface of the printed circuit board body to the first copper block (3), and the bottom of the second blind groove (4) is connected to the first copper block (3); the second copper block (5) is formed by plating copper on the second blind groove (4) and then thickening and filling the second blind groove (4).

2. The copper block printed circuit board according to claim 1, characterized in that, The first copper block (3) and the second copper block (5) are formed by electroplating or electrodeposition.

3. A method for manufacturing a high-efficiency heat-dissipating copper block printed circuit board, characterized in that, Includes the following steps: The first surface of the printed circuit board body (1) is subjected to a router blinding process to obtain a first blind groove (2); the depth of the first blind groove (2) is 55%-60% of the thickness of the printed circuit board body (1); The first blind slot (2) is subjected to copper plating to obtain the first copper block (3) located inside the first blind slot (2); The printed circuit board body (1) with copper plating treatment and the first copper block (3) is electroplated all over the board; The printed circuit board body (1) with full plated electroplating is subjected to pattern dry film treatment; and pattern electroplating and film removal treatment are performed after pattern dry film treatment to thicken the first copper block (3) and fill the first blind groove (2); The first surface of the printed circuit board body (1) after the film is removed is subjected to electroplating and grinding treatment to obtain a first copper block (3) with a flat surface; The second side of the printed circuit board body (1) is subjected to a router blinding process to obtain a second blind groove (4); the bottom of the second blind groove (4) is connected to the first copper block (3); The second blind slot (4) is subjected to copper plating treatment to obtain a second copper block (5) located inside the second blind slot (4) and connected to the first copper block (3); The printed circuit board body (1) with copper plating treatment and having a first copper block (3) and a second copper block (5) is electroplated again. The printed circuit board body (1) with full plated electroplating is subjected to pattern dry film treatment; after the printed circuit board body (1) is subjected to pattern dry film treatment, pattern electroplating and film removal treatment are performed to thicken the second copper block (5) and fill the second blind groove (4). The second surface of the printed circuit board body (1) after the film is removed is subjected to electroplating and grinding treatment to obtain a second copper block (5) with a flat surface; After obtaining the first copper block (3) and the second copper block (5), the printed circuit board body (1) is subjected to surface copper reduction treatment, then subjected to the third copper plating treatment and pattern dry film treatment, and then subjected to pattern electroplating copper and tin and film stripping etching to obtain the copper block printed circuit board.

4. The manufacturing method according to claim 3, characterized in that, The steps of performing patterned dry film processing on the printed circuit board body (1) of the full-board electroplating include: Photosensitive dry film is applied to the copper foil surfaces of the first and second sides of the printed circuit board after full electroplating, and then exposed and developed. During the development process, a dilute alkaline solution is used to dissolve the unexposed photosensitive dry film.

5. The manufacturing method according to claim 4, characterized in that, The dilute alkaline solution is a sodium carbonate solution or potassium carbonate solution with a mass concentration of 0.8%-1.2%.

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