Printed Circuit Boards and Their Manufacturing Methods
By setting conductive tubes and conductive materials on the substrate of printed circuit boards with interference or transition fit, the problem of poor adhesion after blind hole electroplating is solved, and the connection reliability is improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- KINWONG ELECTRONIC TECH (ZHUHAI) CO LTD
- Filing Date
- 2025-11-06
- Publication Date
- 2026-05-26
AI Technical Summary
In the prior art, when the thickness-to-diameter ratio of blind vias in multilayer printed circuit boards is large, problems such as inconsistent copper layer thickness, hole bottom depression, or voids are prone to occur after electroplating. This results in poor bonding force between the pins of electronic components and the inner wall of the crimped blind via, affecting the reliability of the connection.
The substrate is formed by stacking and pressing the first sub-board, the dielectric layer and the second sub-board together. The first hole is filled with conductive material, and the second hole passes through the conductive material and is equipped with a conductive tube with interference or transition fit. The conductive material and the conductive tube are electrically connected to achieve the connection between the component pin and the conductive tube.
This improves the bonding force between the pins and the inner wall of the crimped blind hole after the electronic components are crimped, thus enhancing the reliability of the connection.
Smart Images
Figure CN121078650B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of printed circuit board manufacturing technology, specifically to a printed circuit board and its manufacturing method. Background Technology
[0002] Vias on a printed circuit board (PCB) are used to establish electrical connections between different layers. Common via types include: through-hole vias, which extend from the top layer to the bottom layer; blind vias, which connect an outer layer to one or more inner layers; and buried vias, which connect to inner layers but do not contact the surface layer.
[0003] In some multilayer, high-density printed circuit boards (PCBs), blind vias are designed as crimp holes to increase wiring density. These vias are used to achieve electrical connection and mechanical fixation between components and the PCB through mechanical crimping. During PCB fabrication, the drilling depth is controlled according to the layers to be connected to create the blind vias. Then, electroplating is used to plate metal onto the sidewalls and bottom of the blind vias to meet electrical connection requirements, resulting in crimped blind vias. However, this process is limited by the depth of the blind via plating. When the thickness-to-diameter ratio of the blind via is large (e.g., exceeding 1:1), problems such as inconsistent copper layer thickness, bottom depressions or voids, and thin copper layers can easily occur after electroplating. Therefore, it is impossible to manufacture crimped blind vias with large thickness-to-diameter ratios.
[0004] Therefore, a solution has emerged that uses copper paste to plug the holes and then drills them to achieve electrical conductivity instead of electroplating blind holes. However, in this solution, after the electronic components are pressed into the crimped blind holes, the bonding force between the pins of the electronic components and the inner wall of the crimped blind holes is poor, which can easily lead to reliability problems. Summary of the Invention
[0005] This application provides a printed circuit board and a method for manufacturing the same, which improves the problem of poor bonding force between the pins of electronic components and the inner wall of the crimped blind hole in the related art.
[0006] In a first aspect, embodiments of this application provide a method for manufacturing a printed circuit board, comprising:
[0007] A first sub-board, a dielectric layer, and a second sub-board are stacked and pressed together to obtain a substrate. The first sub-board is provided with a first circuit layer and a first hole. The first hole penetrates the first circuit layer along the arrangement direction of the first sub-board and the second sub-board. The first hole is filled with a conductive material. The first circuit layer is connected to the conductive material and is electrically conductive.
[0008] A second hole is formed on the substrate, the second hole penetrating the conductive material along the arrangement direction of the first sub-plate and the second sub-plate, the conductive material defining at least a portion of the inner sidewall of the second hole;
[0009] A conductive tube is disposed in the second hole, and the conductive tube is interference-fitted or transition-fitted with the second hole. The conductive material is connected to the conductive tube and is electrically conductive.
[0010] In some embodiments, the outer diameter of the end of the conductive tube facing the bottom of the second hole is smaller than the outer diameter of the end of the conductive tube facing away from the bottom of the second hole.
[0011] In some embodiments, the length of the conductive tube is less than the depth of the second hole.
[0012] In some embodiments, the second hole is coaxially arranged with the first hole, and the diameter of the second hole is smaller than the diameter of the first hole.
[0013] In some embodiments, before the first sub-board and the second sub-board are stacked and pressed together to obtain the substrate, the printed circuit board and its manufacturing method further include:
[0014] The first hole is machined on the first sub-plate;
[0015] The conductive material is filled into the first hole.
[0016] In some embodiments, filling the first hole with the conductive material includes:
[0017] The first hole is subjected to a hole metallization process to obtain an electroplated layer located on the inner sidewall of the first hole;
[0018] The first hole is filled with conductive paste, and the conductive paste is baked and cured to obtain a filling part that is connected to the electroplated layer and electrically conductive. The conductive material includes the electroplated layer and the filling part.
[0019] In some embodiments, the conductive paste has a volume resistivity less than or equal to (2 × 10⁻⁶). -4 Copper paste with a density of Ω·cm.
[0020] Secondly, embodiments of this application provide a printed circuit board, including a substrate. The substrate includes a first sub-board, a dielectric layer, and a second sub-board stacked together. The first sub-board has a first circuit layer and a first hole. The first hole penetrates the first circuit layer along the arrangement direction of the first and second sub-boards. The first hole is filled with a conductive material, and the first circuit layer is connected to and electrically connected to the conductive material. A second hole is provided on the substrate. The second hole penetrates the conductive material along the arrangement direction of the first and second sub-boards. The conductive material defines at least a portion of the inner sidewall of the second hole. A conductive tube is disposed in the second hole. The conductive tube is interference-fitted or transition-fitted with the second hole, and the conductive material is connected to and electrically connected to the conductive tube.
[0021] In some embodiments, the outer diameter of the end of the conductive tube facing the bottom of the second hole is smaller than the outer diameter of the end of the conductive tube facing away from the bottom of the second hole.
[0022] In some embodiments, the length of the conductive tube is less than the depth of the second hole.
[0023] In some embodiments, the second hole is coaxially arranged with the first hole, and the diameter of the second hole is smaller than the diameter of the first hole.
[0024] Thirdly, embodiments of this application provide a printed circuit board, which is manufactured by the printed circuit board manufacturing method described in the first aspect.
[0025] The printed circuit board manufacturing method provided in this application has the following advantages: First, a first sub-board, a dielectric layer, and a second sub-board are stacked and pressed together to obtain a substrate. The first sub-board has a first circuit layer and a first hole. The first hole penetrates the first circuit layer along the arrangement direction of the first and second sub-boards. The first hole is filled with conductive material, and the first circuit layer is connected to and electrically conductive with the conductive material. Then, a second hole is processed on the substrate. The second hole penetrates the conductive material along the arrangement direction of the first and second sub-boards, and the conductive material defines at least a portion of the inner wall of the second hole. Next, a conductive tube is placed in the second hole. The conductive tube is interference-fitted or transition-fitted with the second hole, and the conductive material is connected to and electrically conductive with the conductive tube. Therefore, the pins of components can be pressed into the conductive tube and connected to the first circuit layer through the conductive tube and conductive material. Thus, the inner hole of the conductive tube can be used as a crimp-in blind hole. Because the conductive tube has higher hardness, the bonding force between the crimped pins of electronic components and the inner wall of the crimp-in blind hole can be improved, thereby increasing connection reliability.
[0026] The advantages of the printed circuit board provided in this application compared to the prior art can be seen in the description of the advantages of the manufacturing method of the printed circuit board provided in this application compared to the prior art, which will not be repeated here. Attached Figure Description
[0027] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 This is a flowchart of a method for manufacturing a printed circuit board in one embodiment of this application;
[0029] Figure 2 This is a schematic diagram of the structure of the first sub-board in one embodiment of this application;
[0030] Figure 3 Is Figure 2 A schematic diagram showing the first hole of the first sub-board filled with conductive material.
[0031] Figure 4 It is Figure 2 The first sub-board, the dielectric layer, and the second sub-board are stacked and pressed together to obtain a schematic diagram of the substrate structure.
[0032] Figure 5 Is Figure 2 A schematic diagram showing the fabrication of a second hole on the substrate;
[0033] Figure 6 Is Figure 5 A schematic diagram showing a conductive tube disposed in the second hole of the substrate.
[0034] Figure 7 yes Figure 6 The top view of the substrate and conductive tube shown.
[0035] The markings in the diagram mean:
[0036] 10. First sub-board;
[0037] 101. First hole; 102. Conductive material; 11. First circuit layer; 12. Electroplating layer; 13. Conductive paste;
[0038] 20. Dielectric layer;
[0039] 30. Second sub-board;
[0040] 31. Second line layer;
[0041] 40. Second hole;
[0042] 50. Conductive tube. Detailed Implementation
[0043] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0044] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.
[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0046] In this specification, references to "one embodiment," "some embodiments," or "embodiment" mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. Furthermore, in one or more embodiments, specific features, structures, or characteristics may be combined in any suitable manner.
[0047] Vias on printed circuit boards are used to establish electrical connections between different layers. Common via types include: through-hole vias, which extend from the top layer to the bottom layer; blind vias, which connect an outer layer to one or more inner layers; and buried vias, which connect inner layers but do not contact the surface layer.
[0048] In some multilayer, high-density printed circuit boards (PCBs), blind vias are designed as crimp holes to increase wiring density. These vias are used to achieve electrical connection and mechanical fixation between components and the PCB through mechanical crimping. During PCB fabrication, the drilling depth is controlled according to the layers to be connected to create the blind vias. Then, electroplating is used to plate metal onto the sidewalls and bottom of the blind vias to meet electrical connection requirements, resulting in crimped blind vias. However, this process is limited by the depth of the blind via plating. When the thickness-to-diameter ratio of the blind via is large (e.g., exceeding 1:1), problems such as inconsistent copper layer thickness, bottom depressions or voids, and thin copper layers can easily occur after electroplating. Therefore, it is impossible to manufacture crimped blind vias with large thickness-to-diameter ratios.
[0049] Therefore, a solution has emerged that uses copper paste to plug the holes and then drills them to achieve electrical conductivity instead of electroplating blind holes. However, in this solution, after the electronic components are pressed into the crimped blind holes, the inner wall of the crimped blind holes is relatively soft due to the insufficient hardness of the copper paste. This results in poor bonding between the pins of the electronic components and the inner wall of the crimped blind holes, which can easily lead to reliability problems.
[0050] In view of this, this application provides a printed circuit board and a method for manufacturing the same. First, a first sub-board, a dielectric layer, and a second sub-board are stacked and pressed together to obtain a substrate. The first sub-board has a first circuit layer and a first hole. The first hole penetrates the first circuit layer along the arrangement direction of the first and second sub-boards. The first hole is filled with a conductive material, and the first circuit layer is connected to and electrically conductive with the conductive material. Then, a second hole is processed on the substrate. The second hole penetrates the conductive material along the arrangement direction of the first and second sub-boards, and the conductive material defines at least a portion of the inner wall of the second hole. Next, a conductive tube is placed in the second hole. The conductive tube has an interference fit or a transition fit with the second hole, and the conductive material is connected to and electrically conductive with the conductive tube. Therefore, the pins of electronic components can be pressed into the conductive tube and connected to the first circuit layer through the conductive tube and conductive material. Thus, the inner hole of the conductive tube can be used as a crimp-in blind hole. Because the conductive tube has higher hardness, the bonding force between the crimped pins of electronic components and the inner wall of the crimp-in blind hole can be improved, thereby improving connection reliability.
[0051] To illustrate the technical solution of this application, the following description is provided in conjunction with specific accompanying drawings and embodiments.
[0052] Please refer to Figures 1 to 7 This application provides a method for manufacturing a printed circuit board, including:
[0053] S100: The first sub-board 10, the dielectric layer 20 and the second sub-board 30 are stacked and pressed together to obtain a substrate. The first sub-board 10 is provided with a first circuit layer 11 and a first hole 101. The first hole 101 penetrates the first circuit layer 11 along the arrangement direction of the first sub-board 10 and the second sub-board 30. The first hole 101 is filled with a conductive material 102. The first circuit layer 11 is connected to the conductive material 102 and is electrically conductive.
[0054] The dielectric layer 20 can be a prepreg, etc. The material of the first circuit layer 11 can be copper, silver, or aluminum, etc. The first circuit layer 11 can be one or more layers, and an insulating layer is provided between adjacent first circuit layers 11. Part or all of the first circuit layers 11 are connected to the conductive material 102 and are electrically conductive. The first hole 101 penetrates the first sub-board 10.
[0055] The second sub-board 30 may be provided with a second circuit layer 31, which may have one or more layers, and an insulating layer is provided between adjacent second circuit layers 31. For example, the substrate is an 8-layer circuit board, and the fabrication of other holes on the substrate can refer to conventional processes.
[0056] The conductive material 102 can be made of copper, silver, or aluminum, etc. The material of the conductive material 102 can be the same as that of the first circuit layer 11. The conductive material 102 can be placed inside the first hole 101 by electroplating or via plugging.
[0057] S200: A second hole 40 is formed on the substrate. The second hole 40 penetrates the conductive material 102 along the arrangement direction of the first sub-plate 10 and the second sub-plate 30. The conductive material 102 defines at least a portion of the inner sidewall of the second hole 40.
[0058] The second hole 40 can be drilled on the substrate by mechanical drilling, laser drilling, or a combination of both.
[0059] The second hole 40 can be coaxially arranged with the first hole 101, and the conductive material 102 can define the entire inner wall of the second hole 40.
[0060] It is understandable that the second hole 40 can be used as a crimping blind hole, so that the pin of the component can be crimped into the second hole 40 directly and connected to the first circuit layer 11 through the conductive material 102. After the second hole 40 is processed on the substrate, there is no need to perform electroplating, so it is relatively convenient to make crimping blind holes with a large thickness.
[0061] S300: A conductive tube 50 is provided in the second hole 40. The conductive tube 50 is interference-fitted or transition-fitted with the second hole 40. The conductive material 102 is connected to the conductive tube 50 and is electrically conductive.
[0062] Since the conductive material 102 fills the first hole 101 (i.e., the conductive material 102 is formed within the first hole 101), and the conductive tube 50 can be pre-processed before being inserted into the second hole 40, the hardness of the conductive tube 50 can be greater than the hardness of the conductive material 102. The conductive tube 50 can be a hollow metal tube or a hollow non-metal tube, and can be a tubular structure that adapts to the shape of the second hole 40 and has at least one open end. The material of the conductive tube 50 can be copper, silver, or aluminum, etc. The conductive tube 50 can be processed by machining or casting. The conductive tube 50 can be inserted into the second hole 40.
[0063] For example, the conductive tube 50 is interference-fitted with the second hole 40. This improves the bonding strength between the conductive material 102 and the conductive tube 50.
[0064] As an implementable embodiment, the printed circuit board provided in this application includes a substrate. The substrate includes a first sub-board 10, a dielectric layer 20, and a second sub-board 30 stacked together. The first sub-board 10 is provided with a first circuit layer 11 and a first hole 101. The first hole 101 penetrates the first circuit layer 11 along the arrangement direction of the first sub-board 10 and the second sub-board 30. The first hole 101 is filled with a conductive material 102. The first circuit layer 11 is connected to and electrically connected to the conductive material 102. A second hole 40 is provided on the substrate. The second hole 40 penetrates the conductive material 102 along the arrangement direction of the first sub-board 10 and the second sub-board 30. The conductive material 102 defines at least a portion of the inner sidewall of the second hole 40. A conductive tube 50 is provided in the second hole 40. The conductive tube 50 is interference-fitted or transition-fitted with the second hole 40. The conductive material 102 is connected to and electrically connected to the conductive tube 50.
[0065] As can be seen from the above, the printed circuit board and its manufacturing method provided in this application firstly stack and press together a first sub-board 10, a dielectric layer 20, and a second sub-board 30 to obtain a substrate. The first sub-board 10 is provided with a first circuit layer 11 and a first hole 101. The first hole 101 penetrates the first circuit layer 11 along the arrangement direction of the first sub-board 10 and the second sub-board 30. The first hole 101 is filled with a conductive material 102. The first circuit layer 11 is connected to the conductive material 102 and is electrically conductive. Then, a second hole 40 is processed on the substrate. The second hole 40 is along the arrangement direction of the first sub-board 10 and the second sub-board 30. The conductive material 102 extends through the second hole 40, defining at least a portion of its inner wall. A conductive tube 50 is then disposed within the second hole 40, with the conductive tube 50 either interference-fitted or transition-fitted to the second hole 40. The conductive material 102 is connected to and electrically conductively connected to the conductive tube 50, allowing the component's pin to be crimped into the conductive tube 50 and connected to the first circuit layer 11 via the conductive tube 50 and the conductive material 102. This enables the inner hole of the conductive tube 50 to serve as a crimp-in blind hole. Because the conductive tube 50 has higher hardness, it can improve the bonding force between the crimped pin of the electronic component and the inner wall of the crimp-in blind hole, thereby improving connection reliability.
[0066] Optionally, the outer diameter of the end of the conductive tube 50 facing the bottom of the second hole 40 is smaller than the outer diameter of the end of the conductive tube 50 facing away from the bottom of the second hole 40.
[0067] This design facilitates the insertion of the conductive tube 50 into the second hole 40.
[0068] Optionally, the length of the conductive tube 50 is less than the depth of the second hole 40.
[0069] This configuration allows the conductive tube 50 to be installed inside the second hole 40 without protruding from the surface of the first sub-board 10, thus preventing it from affecting normal use.
[0070] Optionally, the second hole 40 is coaxially arranged with the first hole 101, and the diameter of the second hole 40 is smaller than the diameter of the first hole 101.
[0071] This configuration allows the conductive material 102 to define the entire inner wall of the second hole 40, thereby enabling the pins of electronic components to connect to and be electrically connected with a larger amount of conductive material 102, and facilitating the fabrication of the second hole 40.
[0072] As an implementable method, the second hole 40 is coaxially arranged with the first hole 101, the diameter of the second hole 40 is smaller than the diameter of the first hole 101, and after the second hole 40 is processed on the substrate, a conductive tube 50 is provided in the second hole 40.
[0073] This configuration allows the conductive material 102 to define the entire inner wall of the second hole 40, thereby enabling the conductive tube 50 to be connected to and electrically conductive with a larger amount of conductive material 102, and facilitating the fabrication of the second hole 40.
[0074] Please refer to Figure 2 and Figure 3 In some embodiments, before obtaining the substrate, the printed circuit board and its manufacturing method further include: (The text abruptly ends here, so the translation stops as well.)
[0075] First, the first hole 101 is machined on the first daughter plate 10.
[0076] The first hole 101 can be machined on the first sub-board 10 by mechanical drilling, laser drilling, or a combination of both. Mechanical drilling is preferred due to its higher drilling efficiency.
[0077] Next, conductive material 102 is filled into the first hole 101.
[0078] Conductive material 102 can be provided in the first hole 101 by electroplating or plugging.
[0079] By adopting the above scheme, the first sub-board 10 can be obtained relatively easily.
[0080] Optionally, the first hole 101 is filled with a conductive material 102, including:
[0081] First, the first hole 101 is subjected to hole metallization treatment to obtain an electroplated layer 12 located on the inner sidewall of the first hole 101.
[0082] Next, conductive paste 13 is filled into the first hole 101 and the conductive paste 13 is baked and cured to obtain a filling part that is connected to the electroplated layer 12 and electrically conductive. The conductive material 102 includes the electroplated layer 12 and the filling part.
[0083] By adopting the above scheme, conductive material 102 can be filled into the first hole 101 relatively easily.
[0084] It should be noted that the conductive paste 13 can be inserted into the first hole 101 by screen printing or aluminum sheet plugging. When plugging the hole, attention should be paid to filling it fully without depressions. After plugging the hole, the conductive paste 13 should be pre-cured, the paste overflowing from the board surface should be removed by grinding, and then baked to cure.
[0085] It is understandable that the hardness of the conductive material 102 obtained by the above method is less than the hardness of the conductive tube 50.
[0086] Optionally, the conductive paste 13 has a volume resistivity less than or equal to (2 × 10⁻⁶). -4Copper paste with a density of Ω·cm.
[0087] This configuration allows the conductive paste 13 to have better conductivity.
[0088] Please refer to Figures 1 to 7 This application provides a printed circuit board, which is manufactured by the printed circuit board manufacturing method of the first aspect.
[0089] The printed circuit board provided in this application embodiment involves first stacking and pressing a first sub-board 10, a dielectric layer 20, and a second sub-board 30 together to obtain a substrate. The first sub-board 10 has a first circuit layer 11 and a first hole 101. The first hole 101 penetrates the first circuit layer 11 along the arrangement direction of the first sub-board 10 and the second sub-board 30. The first hole 101 is filled with a conductive material 102, and the first circuit layer 11 is connected to and electrically conductive with the conductive material 102. Then, a second hole 40 is processed on the substrate, and the second hole 40 penetrates the conductive material 101 along the arrangement direction of the first sub-board 10 and the second sub-board 30. Material 102, a conductive material 102, defines at least a portion of the inner wall of the second hole 40. Then, a conductive tube 50 is disposed in the second hole 40. The conductive tube 50 is interference-fitted or transition-fitted with the second hole 40. The conductive material 102 is connected to the conductive tube 50 and is electrically conductive, so the pins of the components can be pressed into the conductive tube 50 and connected to the first circuit layer 11 through the conductive tube 50 and the conductive material 102. Thus, the inner hole of the conductive tube 50 can be used as a crimping blind hole. Because the conductive tube 50 has higher hardness, the bonding force between the pins of the electronic components after crimping and the inner wall of the crimping blind hole can be improved, thereby improving the connection reliability.
[0090] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. A method for manufacturing a printed circuit board, characterized in that, include: A first sub-board, a dielectric layer, and a second sub-board are stacked and pressed together to obtain a substrate. The first sub-board is provided with a first circuit layer and a first hole. The first hole penetrates the first circuit layer along the arrangement direction of the first sub-board and the second sub-board. The first hole is filled with a conductive material. The first circuit layer is connected to the conductive material and is electrically conductive. A second hole is formed on the substrate by mechanical drilling and / or laser drilling. The second hole penetrates the conductive material along the arrangement direction of the first sub-board and the second sub-board, and the conductive material defines at least a portion of the inner sidewall of the second hole. A conductive tube, machined or cast, is inserted into the second hole. The hardness of the conductive tube is greater than that of the conductive material. The conductive tube is a hollow metal tube or a hollow non-metal tube. The conductive tube is interference-fitted or transition-fitted with the second hole. The conductive material is connected to the conductive tube and is electrically conductive. The inner hole of the conductive tube is used as a crimp blind hole for crimping in the pins of components.
2. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The outer diameter of the end of the conductive tube facing the bottom of the second hole is smaller than the outer diameter of the end of the conductive tube facing away from the bottom of the second hole.
3. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The length of the conductive tube is less than the depth of the second hole.
4. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The second hole is coaxially arranged with the first hole, and the diameter of the second hole is smaller than the diameter of the first hole.
5. The method for manufacturing a printed circuit board according to any one of claims 1 to 4, characterized in that, Before the first sub-board and the second sub-board are stacked and pressed together to obtain the substrate, the printed circuit board and its manufacturing method further include: The first hole is machined on the first sub-plate; The conductive material is filled into the first hole.
6. The method for manufacturing a printed circuit board according to claim 5, characterized in that, The step of filling the first hole with the conductive material includes: The first hole is subjected to a hole metallization process to obtain an electroplated layer located on the inner sidewall of the first hole; The first hole is filled with conductive paste, and the conductive paste is baked and cured to obtain a filling part that is connected to the electroplated layer and electrically conductive. The conductive material includes the electroplated layer and the filling part.
7. The method for manufacturing a printed circuit board according to claim 6, characterized in that, The conductive paste has a volume resistivity less than or equal to (2×10⁻⁶). -4 Copper paste with a density of Ω·cm.
8. A printed circuit board, characterized in that, The system includes a substrate comprising a first sub-board, a dielectric layer, and a second sub-board stacked together. The first sub-board has a first circuit layer and a first hole extending through the first circuit layer along the arrangement direction of the first and second sub-boards. The first hole is filled with a conductive material, and the first circuit layer is connected to and electrically connected to the conductive material. A second hole is provided on the substrate, extending through the conductive material along the arrangement direction of the first and second sub-boards. The conductive material defines at least a portion of the inner sidewall of the second hole. A conductive tube, machined by machining or casting, is disposed within the second hole. The hardness of the conductive tube is greater than the hardness of the conductive material. The conductive tube is a hollow metal tube or a hollow non-metal tube. The conductive tube is interference-fitted or transition-fitted with the second hole. The conductive material is connected to and electrically connected to the conductive tube. The inner hole of the conductive tube is used as a crimp-in blind hole for crimping in component pins.
9. The printed circuit board according to claim 8, characterized in that, The outer diameter of the end of the conductive tube facing the bottom of the second hole is smaller than the outer diameter of the end of the conductive tube facing away from the bottom of the second hole.
10. The printed circuit board according to claim 8, characterized in that, The length of the conductive tube is less than the depth of the second hole.
11. The printed circuit board according to any one of claims 8 to 10, characterized in that, The second hole is coaxially arranged with the first hole, and the diameter of the second hole is smaller than the diameter of the first hole.
12. A printed circuit board, characterized in that, The printed circuit board is manufactured by the printed circuit board manufacturing method as described in any one of claims 1 to 7.