Ultra-thin circuit board manufacturing method and circuit board

Abstract

The invention discloses an ultrathin circuit board manufacturing method and a circuit board, and the method comprises the following steps: taking a board: taking a copper-clad plate, and dividing a region: dividing the outer surface of the copper-clad plate into a functional region and a blank region after taking the board; the copper-clad plate is thinned, after the area is divided, a copper etching liquid medicine is used for etching a functional area so as to reduce the thickness of the functional area, the functional area is used for circuit design, and a blank area is arranged around the functional area and used for keeping the rigidity of the copper-clad plate. The number of the functional areas and the number of the blank areas are both multiple, the multiple blank areas are connected with one another and form an enclosed area, and the enclosed area is shaped like a Chinese character'tian '. The supporting frame is defined by the blank area, so that the functional area is thinned to facilitate subsequent circuit pattern manufacturing of an ultrathin circuit board, meanwhile, the rigidity of the whole copper-clad plate can be guaranteed due to the supporting frame formed by the blank area, and it can be guaranteed that the copper-clad plate keeps a stable structure in production operation; for example, stable conveying can be achieved in the conveying process.

Description

Technical Field

[0001] The present invention relates to the field of circuit board manufacturing, and in particular to a method for manufacturing an ultra-thin circuit board, and a circuit board manufactured using the method. Background Art

[0002] Due to the rapid development of electronic technology, the surface of a circuit board, which is occupied by various graphics with specific electrical functions and connections, is now known as the functional area of ​​the circuit board. To improve wiring density and electrical performance, and to achieve miniaturization, multi-functions, high integration, and high power capabilities for circuit boards, the functional area of ​​the circuit board is becoming thinner. In related technologies, the circuit board is processed for overall thinning. However, due to its small thickness, the rigidity and support performance of the circuit board are insufficient. During the production and processing of the circuit board, it is easy for it to get stuck in the equipment when it is moved forward by rollers or conveyor belts, causing production difficulties. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a method for manufacturing an ultra-thin circuit board, which has the advantages of simple operation, low manufacturing cost and improved circuit board quality.

[0004] The present invention also provides a circuit board manufactured using the above-mentioned ultra-thin circuit board manufacturing method.

[0005] The method for manufacturing an ultra-thin circuit board according to the present invention comprises the following steps: Take the board: take the copper clad board; Dividing the area: After taking the board, the outer surface of the copper clad board is divided into functional areas and blank areas; Thinning the copper clad laminate: After dividing the area, use copper etching solution to etch the functional area to reduce the thickness of the functional area. The functional area is used for circuit design, and the blank area is set around the functional area and is used to maintain the rigidity of the copper clad laminate.

[0006] The method for manufacturing ultra-thin circuit boards according to the present invention has at least the following beneficial effects: by dividing the copper-clad laminate into functional areas and blank areas, processing the copper-clad laminate into an outer surface of varying thickness, and enclosing the blank areas to form a support frame, this thinning of the functional areas facilitates the subsequent manufacture of circuit patterns for the ultra-thin circuit board. Furthermore, the presence of the support frame formed by the blank areas ensures the rigidity of the entire copper-clad laminate, enabling it to maintain a stable structure during production operations, such as ensuring smooth transportation during conveying. Furthermore, thinner circuit boards help reduce delays, reflections, and attenuation during signal transmission, thereby improving transmission characteristics and enhancing electromagnetic compatibility, enabling normal operation even in complex electromagnetic environments.

[0007] The method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention further includes the following steps: Applying dry film: Apply dry film to the outer surface of the copper clad laminate in the divided area; Exposure and development: After applying the dry film, perform exposure and development on the copper clad laminate to form the functional areas and the blank areas.

[0008] For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, there are multiple functional areas and multiple blank areas. The multiple blank areas are connected to each other to form an enclosing area, and the multiple functional areas are arranged at intervals within the enclosing area.

[0009] For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, the enclosing area is in a cross shape.

[0010] For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, the copper clad laminate includes a dielectric layer and a copper layer. The copper layer covers the outer surface of the dielectric layer, and both the functional areas and the blank areas are provided on the outer surface of the copper layer. For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, after thinning the copper clad laminate, the thickness of the copper layer at the blank area is A, 17um ≤ A ≤ 35um, and the thickness of the copper layer at the functional area is B, 2um ≤ B ≤ 3um.

[0011] For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, before thinning the copper clad laminate, the thickness of the copper layer is C; during the thinning of the copper clad laminate, the etching depth of the copper etching solution is D, satisfying: 14um ≤ D ≤ 33um, C ≥ D + 2um.

[0012] For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, the copper clad laminate is a single-sided copper clad laminate or a double-sided copper clad laminate.

[0013] For the method for manufacturing an ultra-thin circuit board according to some embodiments of the present invention, there are multiple functional areas and multiple blank areas. The functional areas and the blank areas are arranged alternately and in a grid structure.

[0014] The circuit board according to the present invention includes the method for manufacturing the ultra-thin circuit board according to the present invention.

[0015] The circuit board according to the present invention has at least the following beneficial effects: The circuit board has high signal transmission efficiency, strong electromagnetic compatibility, can work normally in a complex electromagnetic environment, and is convenient for processing and production.

[0016] The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which: Figure 1 This is a flow chart of a method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention; Figure 2 A schematic diagram of a copper-clad laminate according to a method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention; Figure 3 Schematic diagram of dry film application in a method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention; Figure 4 Schematic diagram of exposure and development of a method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention; Figure 5 Schematic diagram of thinning the copper clad laminate in the method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention; Figure 6 A cross-sectional view of a copper-clad laminate according to a method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention; Figure 7 Schematic diagram of the structure of the blank area of ​​the method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention.

[0018] Description of Figure Numbers: Copper clad laminate 100; dielectric layer 1001; copper layer 1002; Dry film 300; blank area 400; Functional area 500. DETAILED DESCRIPTION

[0019] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0020] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0021] In the description of the present invention, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0022] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0023] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0024] With the rapid development of electronic technology, circuit boards are continuously improving towards miniaturization, multi-functions, high integration, and high power, and as a result, they are also becoming thinner. However, circuit boards that are too thin can lack rigidity and support. During production and processing, they can easily become stuck in equipment when traveling on rollers or conveyor belts, causing production difficulties.

[0025] To this end, this embodiment discloses a method for manufacturing an ultra-thin circuit board. The method includes steps S100 to S500. It should be noted that the order of the steps and the actual operation methods described in this embodiment can be adjusted as needed and are not limited to those described in this embodiment.

[0026] like Figures 1 to 7 As shown in FIG, the method for manufacturing an ultra-thin circuit board proposed by the present invention includes the following steps performed in sequence: S100, take out the board: take out the copper clad laminate 100. The copper clad laminate 100 is the base material of the circuit board and undertakes the four major functions of the circuit board: conductivity, insulation, support and signal transmission.

[0027] S200 , dividing the area: After taking the board, the outer surface of the copper clad board 100 is divided into a functional area 500 and a blank area 400 to provide a basis for subsequent processing.

[0028] S500, thinning the copper clad laminate: After dividing the area, use copper etching solution to etch the functional area 500. The copper etching solution will react with the copper in the functional area 500 to reduce the thickness of the functional area 500. Areas of varying thickness are formed on the surface of the copper clad laminate 100. The functional area 500 is used for circuit design, that is, it can be used to arrange conductive circuits, electronic component connection circuits, and specific areas of various circuit patterns. The blank area 400 is set around the functional area 500 and is used to maintain the rigidity of the copper clad laminate 100. The blank area 400 can ensure that the copper clad laminate 100 is not easily deformed or stuck in the equipment during transportation during subsequent processing, transportation, and use, thereby ensuring the stability and reliability of the processing of the entire circuit board.

[0029] In some embodiments of the present invention, Figure 2 As shown, the copper clad laminate 100 includes a dielectric layer 1001 and a copper layer 1002. The dielectric layer 1001 includes a polymer synthetic resin and a reinforcing material. The material of the dielectric layer 1001 can be, but is not limited to, polyimide, polyester resin, polyethylene naphthalate, liquid crystal polymer, and modified polyimide, etc., and this application does not impose any restrictions. The copper layer 1002 covers the outer surface of the dielectric layer 1001. The functional area 500 and the blank area 400 are both arranged on the outer surface of the copper layer 1002. The dielectric layer 1001 has an insulating component that can effectively isolate the copper layer 1002, prevent short circuits between different circuits, and ensure the stability and safety of the circuit. The copper layer 1002 covers the outer surface of the dielectric layer 1001, providing a good conductive foundation for the formation of the circuit. Because copper has good conductivity and ductility, various complex circuit patterns can be easily formed through processes such as etching.

[0030] Furthermore, the copper clad laminate 100 is a single-sided copper clad laminate 100 or a double-sided copper clad laminate 100. Based on the structure of the copper clad laminate 100, it can be divided into single-sided copper clad laminate 100 and double-sided copper clad laminate 100. Single-sided copper clad laminate 100 has a copper layer 1002 on only one side and is mainly used for simple circuits, with relatively low manufacturing costs. Double-sided copper clad laminate 100 has copper layer 1002 on both sides and is suitable for more complex circuits. The copper layers 1002 on both sides of the double-sided copper clad laminate 100 provide more wiring space and connection possibilities for complex circuits, making it particularly suitable for the production of multi-layer circuit boards.

[0031] In some embodiments of the present invention, Figures 2 to 4 As shown, including but not limited to step S300 and step S400.

[0032] Step S300, Dry Film Application: In the designated areas, a dry film 300 is applied to the outer surface of the copper-clad laminate 100. The dry film 300 has good adhesiveness and photosensitivity and is pressed against at least one side of the copper-clad laminate 100. In this embodiment, the dry film 300 is pressed against both the top and bottom sides of the copper-clad laminate 100, specifically the surface of the copper layer 1002 facing away from the substrate. The dry film 300 can be made of, but is not limited to, styrene, maleic acid, or acrylate.

[0033] Step S400, Exposure and Development: After the dry film 300 is applied, the copper clad laminate 100 is exposed and developed. The upper and lower sides of the copper clad laminate 100 are exposed, so that the dry film 300 has exposed portions and unexposed portions. The dry film 300 is exposed to a polymerization reaction, and the product structure of this polymerization reaction is relatively stable. The unexposed portion is removed by development to form the functional area 500 and the blank area 400. The hollow area formed after removing the unexposed portion forms the functional area 500. In other embodiments, the exposed portion is removed by development, and the hollow area formed after removing the exposed portion forms the functional area 500. The functional area 500 and the blank area 400 can be used for subsequent processing.

[0034] In some embodiments of the present invention, Figures 5 to 7 As shown, there are multiple functional areas 500 and blank areas 400. The multiple blank areas 400 are interconnected and form an enclosed area, which improves the overall strength of the copper clad laminate 100. The multiple blank areas 400 form a framework structure. These blank areas 400 work together, and the multiple functional areas 500 are spaced apart within the enclosed area, providing stable support for the copper clad laminate 100 when subjected to external forces. The framework structure formed by the blank areas 400 can effectively prevent deformation of the copper clad laminate 100, ensuring that the circuits within the functional areas 500 can operate normally under various operating conditions.

[0035] Specifically, such as Figure 7 As shown, the closed structure can improve the compressive and torsional resistance of the frame structure. The enclosed area is in the shape of a field. The rectangular frames around it can evenly distribute the external pressure to the entire frame. The blank area 400 in the middle of the enclosed area, that is, the cross-shaped frame, provides support for the rectangular frame. The frame structure has good connections in all directions, which improves the rigidity of the circuit board.

[0036] In other embodiments of the present invention (not shown in the figures), there are multiple functional areas and blank areas, which are staggered and arranged in a tic-tac-toe structure. The functional areas and blank areas in the tic-tac-toe structure cooperate with each other to form a mesh-like tic-tac-toe reinforcement structure, in which the blank areas play a role similar to a "skeleton", which is used to improve the rigidity of the copper clad laminate, reduce the possibility of warping or bending, and improve the adaptability of the copper clad laminate in different application scenarios.

[0037] In some embodiments of the present invention, reference Figure 6 and Figure 7 After step S500, that is, after thinning the copper clad laminate 100, the dry film 300 covering the outer surface of the copper clad laminate 100 is removed, and then the copper clad laminate 100 is subjected to subsequent processing. At this time, the thickness of the copper layer 1002 located in the blank area 400 is A, 17um≤A≤35um. The thickness of the copper layer 1002 in the blank area 400 within this range ensures that the copper clad laminate 100 will not be easily deformed during processing, transportation and use, which is beneficial to the stable operation of subsequent production processes and equipment. The thickness of the copper layer 1002 located in the functional area 500 is B, 2um≤B≤3um. The copper layer 1002 with a thickness of 2um to 3um helps to achieve a shorter signal rise time and more stable signal transmission, thereby improving the operating frequency and data processing capability of the entire circuit, and meeting the requirements of modern electronic equipment for high-speed signal processing.

[0038] In some embodiments of the present invention, reference Figures 4 to 7 Before thinning the copper clad laminate 100, the thickness of the copper layer 1002 is C. During the thinning of the copper clad laminate 100, the copper layer 1002 is thinned using a copper etching solution. The copper etching solution may be, but is not limited to, copper chloride, hydrogen peroxide, hydrochloric acid, or soft water. The etching depth of the copper etching solution is D, satisfying: 14um≤D≤33um, C≥D+2um. The etching depth has a wide range and can adapt to circuit designs of different complexities.

[0039] A circuit board according to an embodiment of the present invention is manufactured using the method for manufacturing an ultra-thin circuit board according to an embodiment of the present invention.

[0040] The circuit board according to the embodiment of the present invention is manufactured by using the ultra-thin circuit board manufacturing method according to the embodiment of the present invention. While the circuit board is thinned, it still maintains a certain rigidity, ensuring normal production operations. The thinner circuit board can reduce signal transmission delay, reflection and attenuation, improve transmission characteristics, and enhance electromagnetic compatibility, so that it can operate normally even in complex electromagnetic environments.

[0041] Other structures and operations of the circuit board according to the embodiment of the present invention are well known to those skilled in the art and will not be described in detail here.

[0042] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A method for manufacturing an ultra-thin circuit board, characterized in that: The following steps are involved: Take the board: take the copper clad board; Dividing the area: After taking the board, the outer surface of the copper clad board is divided into functional areas and blank areas; Thinning the copper clad laminate: After dividing the area, use copper etching solution to etch the functional area to reduce the thickness of the functional area. The functional area is used for circuit design, and the blank area is set around the functional area and is used to maintain the rigidity of the copper clad laminate.

2. The method for manufacturing an ultra-thin circuit board according to claim 1, wherein: The following steps are also included: Applying dry film: applying dry film to the outer surface of the copper clad laminate in the divided area; Exposure and development: After the dry film is applied, the copper clad laminate is exposed and developed to form the functional area and the blank area.

3. The method for manufacturing an ultra-thin circuit board according to claim 1, wherein: There are multiple functional areas and multiple blank areas, and the multiple blank areas are connected to each other to form an enclosed area. The multiple functional areas are arranged at intervals in the enclosed area.

4. The method for manufacturing an ultra-thin circuit board according to claim 3, wherein: The enclosed area is in the shape of a field.

5. The method for manufacturing an ultra-thin circuit board according to claim 1, wherein: The copper clad plate comprises a dielectric layer and a copper layer, wherein the copper layer covers the outer surface of the dielectric layer, and the functional area and the blank area are both arranged on the outer surface of the copper layer.

6. The method for manufacturing an ultra-thin circuit board according to claim 5, wherein: After thinning the copper plate, the thickness of the copper layer located in the blank area is A, 17um≤A≤35um, and the thickness of the copper layer located in the functional area is B, 2um≤B≤3um.

7. The method for manufacturing an ultra-thin circuit board according to claim 5 or 6, wherein: Before the copper clad laminate is thinned, the thickness of the copper layer is C; in the thinned copper clad laminate, the etching depth of the copper etching solution is D, which satisfies: 14um≤D≤33um, C≥D+2um.

8. The method for manufacturing an ultra-thin circuit board according to claim 5, wherein: The copper clad laminate is a single-sided copper clad laminate or a double-sided copper clad laminate.

9. The method for manufacturing an ultra-thin circuit board according to claim 1, wherein: There are multiple functional areas and multiple blank areas, and the functional areas and the blank areas are arranged alternately and in a crisscross structure.

10. A circuit board, characterized in that: The ultra-thin circuit board is manufactured using the method for manufacturing the ultra-thin circuit board according to any one of claims 1 to 9.

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