Manufacturing method of PCB and PCB

Abstract

The application relates to the technical field of printed circuit boards, and discloses a PCB manufacturing method and a PCB. The PCB manufacturing method comprises the following steps: providing a laminated board, wherein the laminated board comprises an inner layer board, a first connecting layer, a first circuit layer and a cleaning plate which are sequentially and laminatedly arranged, the cleaning plate comprises a cleaning layer, and the roughness of the surface of the cleaning layer facing the first circuit layer is greater than the roughness of the surface of the first circuit layer facing the cleaning layer; performing a pressing treatment on the laminated board, so that the inner layer board and the first circuit layer are connected together through the first connecting layer; and removing the cleaning plate to expose the first circuit layer and obtain a first sub-board. The PCB manufacturing method and the PCB provided by the application are used to solve the problem that dust falls on the board surface during the pressing process, residual glue is formed on the board surface after pressing, and the circuit cannot be processed in the subsequent process.

Description

Technical Field

[0001] This application relates to the field of printed circuit board technology, and more particularly to a method for manufacturing a PCB and the PCB itself. Background Technology

[0002] As market demands for higher standards of PCB (Printed Circuit Board) circuit precision and product reliability continue to increase, the complexity of PCB design is also rising. Various PCB products, especially high-end PCBs, employ complex design schemes such as copper foil embedded resistors, multiple laminations, and sub-board pressing.

[0003] In related technologies, conventional PCB boards need to be cut to a fixed size and transferred to the PCB board surface along with the steel plate. The copper foil surface is protected by the steel plate and is not easily contaminated by PP (Prepreg, semi-cured sheet) dust. However, some PCB products use special copper foil designs (such as buried resist copper foil) layers, and the special copper foil is supplied in sheet form. It needs to be manually operated on the lamination and board stacking table. During the process, PP dust from the lamination table, air floating, etc., will inevitably fall onto the board surface. After lamination, residual adhesive will be formed on the board surface, making it impossible to process the circuits in subsequent processes. Summary of the Invention

[0004] This application provides a PCB manufacturing method and a PCB, which solves the problem that dust falls on the board surface during the lamination process, forming residual adhesive on the board surface after lamination, which makes it impossible to process the circuits in subsequent processes.

[0005] In a first aspect, embodiments of this application provide a method for manufacturing a PCB, comprising: A laminated board is provided, the laminated board including an inner layer board, a first connection layer, a first circuit layer and a cleaning board arranged sequentially and stacked, the cleaning board including a cleaning layer, the surface roughness of the cleaning layer facing the first circuit layer is greater than the surface roughness of the first circuit layer facing the cleaning layer. The laminated board is pressed together so that the inner layer board and the first circuit layer are connected together through the first connecting layer; The cleaning board is removed to expose the first circuit layer, thus obtaining the first sub-board.

[0006] In some of these embodiments, the cleaning layer is a metal layer.

[0007] In some of these embodiments, the cleaning layer is browned.

[0008] In some embodiments, the cleaning board further includes a substrate, which is stacked and connected to the cleaning layer, with the cleaning layer located between the substrate and the first circuit layer.

[0009] In some embodiments, the material of the first circuit layer is the same as the material of the cleaning layer.

[0010] In some embodiments, the surface roughness Ra of the cleaning layer facing the first circuit layer is greater than 0.6 μm, and the surface roughness Ra of the first circuit layer facing the cleaning layer is less than 0.3 μm.

[0011] In some embodiments, a conductive layer is provided on the side of the inner layer away from the first connecting layer; before the laminated plates are pressed together, a protective film is attached to the conductive layer on the side away from the first connecting layer; after the laminated plates are pressed together, the protective film is removed.

[0012] In some embodiments, the laminate further includes a second connection layer and a second circuit layer, the second connection layer being located between the inner layer and the second circuit layer.

[0013] In some embodiments, after removing the cleaning board from the first daughter board, the PCB manufacturing method further includes: The first sub-board, the first adhesive layer, and the second sub-board are pressed together, with the first adhesive layer located between the first sub-board and the second sub-board, to obtain a pressed board; The press plate is processed by at least one of reflow soldering, high-temperature baking and horizontal grinding to adjust the coefficient of expansion and contraction of the press plate in its own length direction and / or its own width direction. A second adhesive layer is pressed together with at least two of the pressing plates, the second adhesive layer being located between two adjacent pressing plates to obtain a substrate.

[0014] Secondly, embodiments of this application provide a PCB, which is manufactured by the PCB manufacturing method described in the first aspect.

[0015] The PCB manufacturing method provided in this application has the following advantages: Since the laminated board includes an inner layer board, a first connection layer, a first circuit layer, and a cleaning board arranged sequentially and in a stacked manner, and the cleaning board includes a cleaning layer, the surface roughness of the cleaning layer facing the first circuit layer is greater than the surface roughness of the first circuit layer facing the cleaning layer, and the laminated board is first pressed together so that the inner layer board and the first circuit layer are connected together through the first connection layer, and then the cleaning board is removed to expose the first circuit layer and obtain the first sub-board, when the cleaning board is removed, the dust on the surface of the first circuit layer facing the cleaning layer can be carried away by the surface of the cleaning board facing the first circuit layer, which can avoid the dust forming residual adhesive on the surface of the first circuit layer after pressing, which would prevent the subsequent circuit processing from being impossible.

[0016] The advantages of the PCB provided in this application compared to the prior art can be found in the description of the advantages of the PCB manufacturing method provided in this application compared to the prior art, which will not be repeated here. Attached Figure Description

[0017] 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.

[0018] Figure 1 This is a flowchart of a PCB manufacturing method in one embodiment of this application; Figure 2 This is a schematic diagram of the lamination process of the laminated plates in one embodiment of this application; Figure 3 This is a schematic diagram of the lamination process of the laminated plates in another embodiment of this application; Figure 4 This is a schematic diagram of the lamination process of the laminated plates in another embodiment of this application; Figure 5 This is a schematic diagram of the substrate structure in one embodiment of this application; Figure 6 This is a schematic diagram of a pressing plate being processed by a horizontal grinding plate in one embodiment of this application.

[0019] The markings in the diagram mean: 01. Steel plate; 02. Grinding brush; 1000, substrate; 100. Pressed plate; 10. First sub-board; 11. Inner layer board; 111. Conductive layer; 12. First connecting layer; 13. First circuit layer; 131. PP dust; 14. Cleaning board; 141. Cleaning layer; 142. Substrate; 15. Second connecting layer; 16. Second circuit layer; 17. Protective film; 18. Release film; 20. Third connecting layer; 30. Third line layer; 40. First adhesive layer; 50. Second sub-board; 200. Second adhesive layer. Detailed Implementation

[0020] 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.

[0021] 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.

[0022] 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.

[0023] In this specification, references to "one embodiment," "some embodiments," or simply "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.

[0024] As market demands for higher standards of PCB circuit precision and product reliability continue to increase, the complexity of PCB design is also rising. Various PCB products, especially high-end PCBs, employ complex design schemes such as copper foil embedded resistors, multiple laminations, and sub-board pressing.

[0025] In related technologies, conventional PCB boards need to be cut to a fixed size and transferred to the PCB board surface along with a steel plate. The copper foil surface is protected by the steel plate and is not easily contaminated by PP dust. However, some PCB products use special copper foil designs (such as buried resist copper foil) layers. Since the special copper foil is supplied in sheet form, it needs to be manually operated on the lamination and board stacking table. During the process, PP dust from the lamination table, air floating, etc., will inevitably fall onto the board surface, forming residual adhesive on the board surface after lamination. When the special copper foil lamination thickness is designed to be <0.25mm and asymmetrical lamination is used, due to the thin board and board warping, the residual adhesive formed by PP dust on the board surface cannot be removed by traditional horizontal grinding methods after lamination, resulting in the inability to process the circuits in subsequent processes.

[0026] In view of this, this application provides a method for manufacturing a PCB and a PCB. Since the laminated board includes an inner layer board, a first connection layer, a first circuit layer and a cleaning board arranged sequentially and stacked, and the cleaning board includes a cleaning layer, the surface roughness of the cleaning layer facing the first circuit layer is greater than the surface roughness of the first circuit layer facing the cleaning layer. The laminated board is first laminated so that the inner layer board and the first circuit layer are connected together through the first connection layer. Then the cleaning board is removed to expose the first circuit layer and obtain a first sub-board. Therefore, when the cleaning board is removed, the dust on the surface of the first circuit layer facing the cleaning layer can be removed by the surface of the cleaning board facing the first circuit layer. This can prevent the dust from forming residual adhesive on the surface of the first circuit layer after lamination, which would prevent the subsequent circuit processing from being completed.

[0027] To illustrate the technical solution of this application, the following description is provided in conjunction with specific accompanying drawings and embodiments.

[0028] Please refer to Figure 1 and Figure 2 , Figure 1 This is a flowchart of a PCB manufacturing method in one embodiment of this application. Figure 2 This is a schematic diagram of the lamination process of the laminated plates in one embodiment of this application.

[0029] In a first aspect, embodiments of this application provide a method for manufacturing a PCB, comprising: S100: Provide a laminated board, the laminated board includes an inner layer board 11, a first connection layer 12, a first circuit layer 13 and a cleaning board 14 arranged sequentially and stacked, the cleaning board 14 includes a cleaning layer 141, the surface roughness of the cleaning layer 141 facing the first circuit layer 13 is greater than the surface roughness of the first circuit layer 13 facing the cleaning layer 141.

[0030] The inner layer 11 can be a core board, such as a single-sided copper-clad laminate, a double-sided copper-clad laminate, or a bare core board. The first connecting layer 12 can be a prepreg, etc. The material of the first circuit layer 13 can be copper or a copper-based composite metal, etc. For example, the first circuit layer 13 is a buried resist copper foil, including a 17μm thick copper layer and a 0.5μm thick nickel-chromium alloy layer.

[0031] The surface of the first circuit layer 13 facing the cleaning layer 141 can be a smooth surface with a surface roughness Ra < 0.3 μm, and the surface of the first circuit layer 13 facing away from the cleaning layer 141 can be a rough surface with a surface roughness Ra > 0.6 μm.

[0032] The cleaning layer 141 can be a metallic layer (such as copper, silver, aluminum, etc.) or a non-metallic layer. The cleaning layer 141 may or may not undergo browning treatment. For example, the cleaning layer 141 includes ordinary copper foil or browned core board, which are the most common materials in PCB manufacturing. In actual applications, the cleaning layer 141 is not limited to the above two materials. Other materials with a surface roughness Ra > 0.6μm and a smooth surface can also be used.

[0033] It should be noted that dust (such as PP dust 131) from the pressing table, air float, etc., will inevitably fall on the surface of the first circuit layer 13 facing the cleaning layer 141.

[0034] S200: The laminated board is pressed together so that the inner layer board 11 and the first circuit layer 13 are connected together through the first connecting layer 12.

[0035] The laminated plates can be pressed together using a press machine. Steel plates 01 can be set on both sides of the laminated plates. During the pressing process, the first connecting layer 12 melts and solidifies, connecting the inner layer 11 and the first circuit layer 13 together.

[0036] It should be noted that the characteristic that dust is more likely to adhere to rough surfaces can be utilized to make the dust combine with the surface of the cleaning layer 141 facing the first circuit layer 13 during the pressing process. The dust can be PP dust 131.

[0037] S300: Remove the cleaning board 14 to expose the first circuit layer 13, obtaining the first sub-board 10.

[0038] The cleaning board 14 can be removed by manual tearing or mechanical peeling. The cleaning board 14 can remove the dust on the surface of the first circuit layer 13 facing the cleaning layer 141, thereby reducing the pollution residue on the surface of the first sub-board 10.

[0039] As can be seen from the above, the PCB manufacturing method provided in this application embodiment includes an inner layer board 11, a first connection layer 12, a first circuit layer 13, and a cleaning board 14 arranged sequentially and in a stacked manner. The cleaning board 14 includes a cleaning layer 141. The surface roughness of the cleaning layer 141 facing the first circuit layer 13 is greater than the surface roughness of the first circuit layer 13 facing the cleaning layer 141. The stacked boards are first pressed together so that the inner layer board 11 and the first circuit layer 13 are connected together through the first connection layer 12. Then the cleaning board 14 is removed to expose the first circuit layer 13 and obtain the first sub-board 10. Therefore, when the cleaning board 14 is removed, the dust on the surface of the first circuit layer 13 facing the cleaning layer 141 can be removed by the surface of the cleaning board 14 facing the first circuit layer 13. This can prevent the dust from forming residual adhesive on the surface of the first circuit layer 13 after pressing, which would prevent the subsequent circuit processing from being completed.

[0040] The PCB manufacturing method provided in this application requires no additional equipment, has low implementation cost, and is highly operable.

[0041] Optionally, the cleaning layer 141 is a metal layer.

[0042] This design allows the cleaning layer 141 to have a certain strength, making it easier to adhere to the first circuit layer 13.

[0043] It should be noted that the cleaning layer 141 can be a copper layer, a silver layer, or an aluminum layer, etc. For example, the cleaning layer 141 is a copper foil.

[0044] Please refer to Figure 1 and Figure 3 , Figure 3 This is a schematic diagram of the lamination process of the laminated plates in another embodiment of this application.

[0045] In some of these embodiments, the cleaning layer 141 is browned.

[0046] By adopting the above scheme, the surface roughness of the cleaning layer 141 can be increased, ensuring that the surface roughness of the cleaning layer 141 facing the first circuit layer 13 is greater than the surface roughness of the first circuit layer 13 facing the cleaning layer 141.

[0047] Optionally, the cleaning board 14 further includes a substrate 142, which is stacked and connected to the cleaning layer 141, with the cleaning layer 141 located between the substrate 142 and the first circuit layer 13.

[0048] This configuration can improve the rigidity of the cleaning board 14 through the substrate 142, thereby ensuring the structural integrity of the cleaning board 14 when the dielectric layer is removed. This allows the cleaning board 14 to be repeatedly pressed and peeled off from the first circuit layer 13, enabling the cleaning board 14 to be recycled. This reduces the residual contamination on the surface of the first sub-board 10 while significantly reducing production costs.

[0049] It should be noted that the substrate 142 may include resin and glass fiber, etc.

[0050] It is understandable that if the substrate 142 is not provided and only the cleaning layer 141 is provided, the cleaning layer 141 is prone to deformation and damage after being pressed and separated from the first circuit layer 13, and cannot be used again. It can only be consumed once and is a disposable consumable. The cost of using it in large quantities is high.

[0051] As an implementation method, the cleaning board 14 is a copper-clad laminate, and the cleaning layer 141 is the copper foil of the copper-clad laminate.

[0052] This design allows the cleaning plate 14 to have a simple structure and a certain degree of rigidity.

[0053] Optionally, the material of the first circuit layer 13 is the same as the material of the cleaning layer 141.

[0054] With this configuration, when the laminated board is pressed, the first circuit layer 13 and the cleaning layer 141 will only be physically bonded, and their interface molecules will only come into contact with each other, with almost no strong chemical bond fusion. Therefore, it is easier to peel the cleaning board 14 from the first circuit layer 13 in the future.

[0055] It should be noted that the materials of the first circuit layer 13 and the cleaning layer 141 can be copper, silver or aluminum, etc.

[0056] For example, the first circuit layer 13 is a buried copper foil, the surface of the first circuit layer 13 facing the cleaning layer 141 is a smooth surface, the cleaning layer 141 is a common copper foil of a copper-clad laminate, and the surface of the cleaning layer 141 facing the first circuit layer 13 is a rough surface.

[0057] As an implementation method, the surface roughness Ra of the cleaning layer 141 facing the first circuit layer 13 is greater than 0.6 μm, and the surface roughness Ra of the first circuit layer 13 facing the cleaning layer 141 is less than 0.3 μm.

[0058] This configuration allows the cleaning plate 14 to remove dust from the surface of the first circuit layer 13 facing the cleaning layer 141, preventing dust from forming residual adhesive on the surface of the first circuit layer 13 after pressing, which would prevent subsequent circuit processing from being completed.

[0059] Optionally, the laminate also includes a second connection layer 15 and a second circuit layer 16, wherein the second connection layer 15 is located between the inner layer 11 and the second circuit layer 16.

[0060] This configuration allows the laminated board to simultaneously have a first circuit layer 13 and a second circuit layer 16 after lamination.

[0061] It should be noted that the second connecting layer 15 can be a prepreg, etc. The material of the second circuit layer 16 can be copper, silver, or aluminum, etc.

[0062] Please refer to Figure 1 and Figure 4 , Figure 4 This is a schematic diagram of the lamination process of the laminated plates in another embodiment of this application.

[0063] In some embodiments, a conductive layer 111 is provided on the side of the inner layer 11 facing away from the first connecting layer 12; before the laminate is pressed, a protective film 17 is attached to the side of the conductive layer 111 facing away from the first connecting layer 12; after the laminate is pressed, the protective film 17 is removed.

[0064] By adopting the above solution, the side of the conductive layer 111 facing away from the first connecting layer 12 can be prevented from being exposed to the dust environment by applying the protective film 17 in advance, thereby ensuring that the conductive layer 111 is free from dust pollution and that a horizontal grinding plate is not required after pressing.

[0065] The protective film 17 can be an acid and alkali resistant / high temperature resistant protective film, such as PI (Polyimide) film and PTFE (Polytetrafluoroethylene) film. A release film 18 can be provided between the steel plate 01 and the protective film 17.

[0066] It should be noted that the inner layer 11 needs to be browned before pressing. After the side of the conductive layer 111 facing away from the first connecting layer 12 is browned, the surface becomes rough and cannot be removed by the cleaning plate 14 or by the horizontal grinding plate. Therefore, a protective film 17 can be attached to the side of the conductive layer 111 facing away from the first connecting layer 12.

[0067] Please refer to Figure 1 , Figure 2 , Figure 5 and Figure 6 , Figure 5 This is a schematic diagram of the structure of the substrate 1000 in one embodiment of this application. Figure 6 This is a schematic diagram of the pressing plate 100 being processed by a horizontal grinding plate in one embodiment of this application.

[0068] In some embodiments, after removing the cleaning board 14 from the first daughter board 10, the PCB fabrication method further includes: First, the first sub-plate 10, the first adhesive layer 40, and the second sub-plate 50 are pressed together, with the first adhesive layer 40 located between the first sub-plate 10 and the second sub-plate 50, to obtain the pressed plate 100.

[0069] The first adhesive layer 40 can be a prepreg, etc. The second sub-board 50 can be a single-layer board or a multi-layer board, etc.

[0070] It should be noted that the third connecting layer 20 and the third circuit layer 30 can be stacked sequentially on the side of the first sub-board 10 opposite to the first adhesive layer 40. The third connecting layer 20 can be a prepreg, etc. The material of the third circuit layer 30 can be copper, silver, or aluminum, etc. The first circuit layer 13 and the conductive layer 111 are free of any residual adhesive.

[0071] It is understandable that the laminate 100 can also undergo one or more processing steps such as lamination, resin plugging, and circuit etching, which significantly affect the expansion and contraction coefficient of the laminate 100.

[0072] Secondly, the press plate 100 is treated by at least one of reflow soldering, high-temperature baking and horizontal grinding to adjust the expansion and contraction coefficient of the press plate 100 in its own length direction and / or its own width direction.

[0073] To avoid the problem of layer mismatch caused by the inability of the expansion and contraction coefficients of each layer of the laminate 100 to be completely matched during pressing, and the greater the difference in the expansion and contraction coefficients of the laminate 100, the more serious the layer mismatch after pressing, which leads to abnormal electrical performance of the subsequent substrate 1000, poor interlayer structure reliability, and thus low finished product yield, a "expansion and contraction measurement → expansion and contraction correction" process can be added after resin grinding. Based on the difference in expansion and contraction measurement results, the laminate 100 can be treated by reflow soldering, high temperature baking or horizontal grinding to make the expansion and contraction of each layer of the laminate 100 tend to be consistent.

[0074] Next, the second adhesive layer 200 is pressed together with at least two pressing plates 100, with the second adhesive layer 200 located between two adjacent pressing plates 100, to obtain a substrate 1000.

[0075] By adopting the above scheme, the expansion and contraction coefficients of the pressing plate 100 in different directions can be selectively adjusted by using reflow soldering, high-temperature baking, and horizontal grinding, so that the expansion and contraction coefficients of the pressing plates 100 between different layers tend to be uniform, reducing the impact of the difference in expansion and contraction coefficients of the pressing plates 100 on subsequent pressing.

[0076] The length direction of the pressing plate 100 can be the Y direction, and the width direction of the pressing plate 100 can be the X direction.

[0077] Reflow soldering: The expansion and contraction ratio is adjusted by reflow soldering (the X and Y directions are adjusted simultaneously). With one reflow soldering, the pressure plate 100 shrinks by 3%-5% in both the X and Y directions. Reflow soldering can pull back the pressure plate 100 with large expansion and contraction in both the X and Y directions at the same time, reducing the difference in the expansion and contraction coefficient of the pressure plate 100.

[0078] High-temperature baking: The pressed board 100 is baked at a temperature greater than 160℃, such as 180℃ for 1 hour. The pressed board 100 shrinks by 1%-3% in both the X and Y directions.

[0079] Horizontal grinding: Adjust the expansion / contraction ratio (single-direction adjustment in the X or Y direction) and the sub-board's forward direction (e.g., ...). Figure 6 The direction indicated by the middle arrow a) is perpendicular to the direction of the brush 02 swing (as shown by the middle arrow a). Figure 6(As indicated by arrows b and c) a single grinding operation increases by 0.5%-5%. In addition to high-speed rotation, the grinding brush 02 of the horizontal grinding also swings left and right under a certain pressure applied to the board surface. This can remove foreign matter such as resin and residual glue from the board surface. Furthermore, the left and right swing will give the board surface a large friction force, which will affect the expansion and contraction ratio of the laminate 100 in its swing direction, thereby increasing the expansion and contraction ratio in one direction and reducing the difference in the expansion and contraction coefficient of the sub-boards.

[0080] It should be noted that the above shrinkage and expansion rules will vary depending on the material, thickness, parameters, and equipment configuration of the press plate 100. The variation rules can be collected according to specific processing requirements and then accurately combined and applied. They will not be elaborated here.

[0081] The PCB manufacturing method provided in this application solves the problems of PP dust 131 contamination of the first circuit layer 13 and conductive layer 111 and the mismatch of the pressure expansion and contraction coefficients of the multiple-pressed laminate 100, thereby enhancing electrical performance and interlayer structure reliability, and thus improving the yield of finished products.

[0082] Secondly, embodiments of this application provide a PCB, which is manufactured by the PCB manufacturing method of the first aspect.

[0083] The PCB provided in this application embodiment includes an inner layer board 11, a first connection layer 12, a first circuit layer 13, and a cleaning board 14 arranged sequentially and stacked. The cleaning board 14 includes a cleaning layer 141. The surface roughness of the cleaning layer 141 facing the first circuit layer 13 is greater than the surface roughness of the first circuit layer 13 facing the cleaning layer 141. The PCB is first laminated to connect the inner layer board 11 and the first circuit layer 13 through the first connection layer 12. Then the cleaning board 14 is removed to expose the first circuit layer 13 and obtain the first sub-board 10. Therefore, when the cleaning board 14 is removed, the surface of the cleaning board 14 facing the first circuit layer 13 can remove the dust on the surface of the first circuit layer 13 facing the cleaning layer 141. This can prevent the dust from forming residual adhesive on the surface of the first circuit layer 13 after lamination, which would prevent subsequent circuit processing.

[0084] 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 PCB, characterized in that, include: A laminated board is provided, the laminated board including an inner layer board, a first connection layer, a first circuit layer and a cleaning board arranged sequentially and stacked, the cleaning board including a cleaning layer, the surface roughness of the cleaning layer facing the first circuit layer is greater than the surface roughness of the first circuit layer facing the cleaning layer. The laminated board is pressed together so that the inner layer board and the first circuit layer are connected together through the first connecting layer; The cleaning board is removed to expose the first circuit layer, thus obtaining the first sub-board.

2. The PCB manufacturing method according to claim 1, characterized in that, The cleaning layer is a metal layer.

3. The PCB manufacturing method according to claim 2, characterized in that, The cleaning layer undergoes a browning treatment.

4. The PCB manufacturing method according to claim 2, characterized in that, The cleaning board also includes a substrate, which is stacked and connected to the cleaning layer, with the cleaning layer located between the substrate and the first circuit layer.

5. The PCB manufacturing method according to claim 2, characterized in that, The material of the first circuit layer is the same as the material of the cleaning layer.

6. The PCB manufacturing method according to claim 1, characterized in that, The surface roughness Ra of the cleaning layer facing the first circuit layer is greater than 0.6 μm, and the surface roughness Ra of the first circuit layer facing the cleaning layer is less than 0.3 μm.

7. The PCB manufacturing method according to claim 1, characterized in that, A conductive layer is provided on the side of the inner layer away from the first connecting layer; before the laminated plate is pressed, a protective film is attached to the conductive layer on the side away from the first connecting layer; after the laminated plate is pressed, the protective film is removed.

8. The PCB manufacturing method according to claim 1, characterized in that, The laminated board further includes a second connecting layer and a second circuit layer, wherein the second connecting layer is located between the inner layer board and the second circuit layer.

9. The method for manufacturing a PCB according to any one of claims 1 to 8, characterized in that, After removing the cleaning board from the first sub-board, the PCB manufacturing method further includes: The first sub-board, the first adhesive layer, and the second sub-board are pressed together, with the first adhesive layer located between the first sub-board and the second sub-board, to obtain a pressed board; The press plate is processed by at least one of reflow soldering, high-temperature baking and horizontal grinding to adjust the coefficient of expansion and contraction of the press plate in its own length direction and / or its own width direction. A second adhesive layer is pressed together with at least two of the pressing plates, the second adhesive layer being located between two adjacent pressing plates to obtain a substrate.

10. A PCB, characterized in that, The PCB is manufactured by the PCB manufacturing method as described in any one of claims 1 to 9.

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