PCB golden finger wiring method and device and printed circuit board

Abstract

The invention relates to a PCB golden finger wiring method and device and a printed circuit board, and the method comprises the steps: sequentially carrying out the pressing dry film processing, exposure processing, development processing and etching processing of a multilayer board through an outer layer process, and forming an outer layer circuit on the surface of the multilayer board; wherein the multilayer board comprises an effective golden finger area and an invalid golden finger area, and the outer layer circuit comprises an effective golden finger area; manufacturing a copper layer of an effective golden finger area; according to the method, through the solder mask process, windowing processing is carried out on the welding area of the multilayer board, and solder mask processing is carried out on other areas, except the welding area, of the multilayer board; wherein the welding area comprises an effective golden finger area; and manufacturing the ink layer of the invalid golden finger area. The effective golden finger area has the functions of signal transmission and power supply driving; and the invalid golden finger region plays a role in reinforcing the structure and flattening the plate surface. The thickness uniformity of the golden finger plate of the photoelectric plate is ensured; the production cost is reduced, and the yield of the photoelectric plate golden finger is improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of PCB manufacturing, and in particular to a PCB signal line manufacturing method, device and printed circuit board. Background Art

[0002] With the rapid development of PCB manufacturing industry, the market competition is fierce; LCD optoelectronic panels, i.e. printed circuit boards used in liquid crystal display backlight modules, are widely used and have a larger production volume than other types of circuit boards; however, due to the bonding process characteristics, in the process of manufacturing plasma display modules, it involves the interconnection between flexible circuit boards and rigid circuit boards, so gold surface treatment is required. In the design of gold finger wiring for LCD optoelectronic panels, low-lying areas are easily formed, resulting in uneven board thickness, which leads to low yield of existing LCD optoelectronic panels. Summary of the invention

[0003] In view of the above problems, the embodiments of the present invention provide a PCB board gold finger wiring method, device and printed circuit board, which are used to solve the problem that low-lying areas are easily formed in the gold finger wiring design of LCD optoelectronic panels in the prior art, resulting in uneven board thickness, thereby causing low yield of existing LCD optoelectronic panels.

[0004] According to one aspect of an embodiment of the present invention, a PCB board gold finger wiring method is provided, the method comprising: The previous process is to manufacture a multilayer board and drill holes in the multilayer board; An electroplating process to form a copper layer of a preset thickness on the multilayer board; The outer layer process is to sequentially perform a dry film pressing process, an exposure process, a development process, and an etching process on the multilayer board to form an outer layer circuit on the surface of the multilayer board; wherein the multilayer board includes a valid gold finger area and an invalid gold finger area, and the outer layer circuit includes a valid gold finger area; A solder mask process, performing a window treatment on the soldering area of ​​the multilayer board, and performing a solder mask treatment on other areas of the multilayer board except the soldering area; wherein the soldering area includes an effective gold finger area; A gold deposition process to form a nickel-gold layer in the welding area through a replacement reaction; In the post-process, the multilayer board is formed, electrically tested, finally inspected and packaged.

[0005] In some optional embodiments, the outer layer process specifically includes: Pressed dry film treatment: covering the surface of the copper layer with a photosensitive film; Exposure treatment: exposing the photosensitive film to UV light; Development treatment: dissolve the unpolymerized photosensitive film during the exposure process to expose the copper surface; Etching process: The copper layer exposed on the copper surface is etched away to form the outer layer circuit.

[0006] In some optional embodiments, in the solder mask process, the invalid gold finger area is not subjected to window opening treatment, and the invalid gold finger area is subjected to solder mask treatment to form an ink layer in the invalid gold finger area.

[0007] In some optional embodiments, the ink layer thickness is higher than the copper layer thickness in the effective gold finger area.

[0008] In some optional embodiments, the valid gold finger areas and the invalid gold finger areas are arranged alternately.

[0009] In some optional embodiments, after the solder mask process and before the gold deposition process, a text process is also included, and the text process specifically includes: printing text symbols for identification on the surface of the multilayer board.

[0010] In some optional embodiments, the preceding process specifically includes: Cutting process: the substrate is cut into layers of preset size by a panel splitter, and the layers are baked; Inner layer process: according to the inner layer image and board frame data, the inner layer circuit is made on the layer board; Lamination process: according to the positioning holes of multiple layer boards, multiple layer boards are pressed together to form a multi-layer board at a preset temperature and a preset pressure; Drilling process: drilling via holes between different layers of the multilayer board by using a CNC drill.

[0011] In some optional embodiments, the post-process specifically includes: Forming process: milling the multilayer board after the above-mentioned gold-plating process into single PCS or contiguous circuit boards; Electrical testing process: performing electrical continuity testing on the circuit board; Final inspection process: Conduct final appearance inspection on the circuit boards that have passed the electrical test to select qualified circuit boards; Packaging process: Qualified circuit boards are packaged and shipped according to the material number.

[0012] According to another aspect of an embodiment of the present invention, a PCB board gold finger wiring device is provided, and the device is used to execute the above-mentioned PCB board gold finger wiring method to manufacture a printed circuit board.

[0013] According to another aspect of an embodiment of the present invention, a printed circuit board is provided, wherein the printed circuit board is manufactured by executing the above-mentioned PCB board gold finger wiring method through the above-mentioned PCB board gold finger wiring device.

[0014] The PCB board gold finger wiring method, device and printed circuit board of the present invention have the following beneficial effects: the present invention sequentially performs dry film pressing, exposure, development and etching on the multilayer board through the outer layer process, and forms an outer layer circuit on the surface of the multilayer board; wherein the multilayer board includes an effective gold finger area and an invalid gold finger area, and the outer layer circuit includes the effective gold finger area; a copper layer of the effective gold finger area is produced; the present application performs window opening on the welding area of ​​the multilayer board through the solder mask process, and performs solder mask on other areas of the multilayer board except the welding area; wherein the solder mask includes the effective gold finger area; an ink layer of the invalid gold finger area is produced. The effective gold finger area has the functional role of signal transmission and driving power supply; the invalid gold finger area plays the role of structural reinforcement and board surface flatness. The uniformity of the thickness of the gold finger of the photovoltaic board is guaranteed; the production cost is reduced, and the yield rate of the gold finger of the photovoltaic board is improved.

[0015] The above description is only an overview of the technical solution of the embodiment of the present invention. In order to more clearly understand the technical means of the embodiment of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present invention. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings. In the accompanying drawings: Figure 1 A schematic diagram showing the flow of a PCB board gold finger wiring method according to Embodiment 1 of the present invention is shown; Figure 2 A schematic flow chart of the outer layer process of Example 1 provided by the present invention is shown; Figure 3 The schematic diagram of the process flow of the front process of Example 1 provided by the present invention is shown; Figure 4 The schematic diagram of the structure of the post-process of Example 1 provided by the present invention is shown; Figure 5 A schematic structural diagram of a valid gold finger region and an invalid gold finger region according to Embodiment 1 provided by the present invention is shown. DETAILED DESCRIPTION

[0017] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0018] Embodiment 1, See also Figure 1According to one aspect of an embodiment of the present invention, a PCB board gold finger wiring method is provided. The PCB board gold finger wiring method can be applied to optoelectronic panels such as LCD or LED. The method comprises: 110, a front process, making a multilayer board, and drilling holes in the multilayer board; in step 110, the front process specifically includes: cutting the substrate into layer boards of preset sizes by a board splitter, and baking the layer boards; making inner layer circuits on the layer boards according to the inner layer images and board frame data; aligning the positioning holes of multiple layer boards, pressing the multiple layer boards together to form a multilayer board at a preset temperature and a preset pressure; drilling via holes between different layers of the multilayer board by a CNC drilling machine.

[0019] 120, electroplating process, forming a copper layer of a preset thickness on the multilayer board; in step 120, when electroplating, the multilayer board needs to be placed in an electroplating tank, and then an electrode reaction is performed, so that copper ions are deposited on the surface of the circuit board to form a copper film with uniform thickness and smoothness. Parameters such as electroplating time, current density, temperature, etc. need to be adjusted according to specific conditions to achieve the best effect.

[0020] 130, outer layer process, the multilayer board is subjected to a dry film pressing process, an exposure process, a developing process, and an etching process in sequence to form an outer layer circuit on the surface of the multilayer board; wherein the multilayer board includes a valid gold finger area and an invalid gold finger area, and the outer layer circuit includes a valid gold finger area; in step 130, the outer layer process specifically includes: covering the surface of the copper layer with a photosensitive film; exposing the photosensitive film with UV light; dissolving the photosensitive film that is not polymerized in the exposure process to expose the copper surface; etching and removing the copper layer exposed on the copper surface to form an outer layer circuit.

[0021] 140, solder mask process, performing window treatment on the soldering area of ​​the multilayer board, and performing solder mask treatment on other areas of the multilayer board except the soldering area; wherein the soldering area includes the effective gold finger area; in step 140, the solder mask of the multilayer board is an important step to protect the circuit after etching of the circuit board, which is usually achieved by solder mask ink, also known as green paint or green oil. In the present application, the soldering area of ​​the multilayer board is subjected to window treatment, so that the effective gold finger area is not covered with ink, and only the non-soldering area such as the invalid gold finger area is covered with ink.

[0022] 150, a gold plating process, in which a nickel-gold layer is formed in the welding area by a replacement reaction; in step 150, the principle of gold plating of a multilayer board is mainly to form a nickel-gold composite plating layer on the surface of the circuit board through a chemical gold plating method, also known as nickel immersion gold. This method does not require the use of a complex electroplating process, but attaches nickel and gold to the copper skin through a chemical replacement method.

[0023] 160, post-process, forming, electrical testing, final inspection and packaging of the multilayer board. In step 160, the post-process specifically includes: milling the multilayer board after the gold-plating process into single PCS or connected circuit boards; conducting electrical conductivity testing on the circuit boards and screening out qualified circuit boards; packaging and shipping qualified circuit boards according to material numbers.

[0024] The present invention sequentially performs a dry film pressing process, an exposure process, a development process, and an etching process on the multilayer board through an outer layer process, and forms an outer layer circuit on the surface of the multilayer board; wherein the multilayer board includes an effective gold finger area and an invalid gold finger area, and the outer layer circuit includes an effective gold finger area; a copper layer of the effective gold finger area is produced; the present application performs a window opening process on the welding area of ​​the multilayer board through a solder mask process, and performs a solder mask process on other areas of the multilayer board except the welding area; wherein the welding area includes an effective gold finger area; an ink layer of the invalid gold finger area is produced. The effective gold finger area has the functional role of signal transmission and driving power supply; the invalid gold finger area plays the role of structural reinforcement and board surface flatness. The uniformity of the thickness of the gold finger of the photovoltaic board is guaranteed; the production cost is reduced, and the yield rate of the gold finger of the photovoltaic board is improved.

[0025] In some optional embodiments, see Figure 2 The outer layer process specifically includes: 210, dry film pressing treatment, covering the surface of the copper layer with a photosensitive film; 220, exposure treatment: exposing the photosensitive film by UV light; 230, development treatment: dissolving the unpolymerized photosensitive film in the exposure treatment to expose the copper surface; 240, etching treatment: etching away the copper layer exposed on the copper surface to form an outer layer circuit.

[0026] In some optional embodiments, in the solder mask process, the invalid gold finger area is not subjected to window opening treatment, and the invalid gold finger area is subjected to solder mask treatment so that an ink layer is formed in the invalid gold finger area. Figure 5 , 500 is a multilayer board, 510 is a valid gold finger area, and 520 is an invalid gold finger area. The valid gold finger area 510 and the invalid gold finger area 520 are alternately arranged. The thickness of the ink layer in the invalid gold finger area is higher than the thickness of the copper layer in the valid gold finger area. The thickness of the ink layer in the invalid gold finger area is 35um-45um, and the thickness of the copper layer in the valid gold finger area is 31um-41um; so that the thickness of the gold finger board of the LCD optoelectronic panel is relatively uniform. In a specific example, the thickness of the ink layer in the invalid gold finger area is 43.17um; the thickness of the copper layer in the valid gold finger area is 35.12um.

[0027] In some optional embodiments, after the solder mask process and before the gold deposition process, a text process is further included, and the text process specifically includes: printing text symbols for identification on the surface of the multilayer board. In this embodiment, various text symbols are printed on the multilayer board for easy identification.

[0028] In some optional embodiments, see Figure 3 , the front process specifically includes: 310, cutting process: cutting the substrate into layers of preset size by a board splitter, and baking the layers; 320, inner layer process: making inner layer circuits on the layers according to the inner layer image and board frame data; 330, pressing process: according to the positioning holes of multiple layers, pressing multiple layers to form a multilayer board by preset temperature and preset pressure; 340, drilling process: drilling through holes between different layers of the multilayer board by a CNC drill. In this embodiment, steps 310-340 are used to cut the large-sized substrate into working size and process and bake it to prepare for the production of inner layer circuits; make inner layer graphics and board frame data; according to the positioning holes of the inner layer, press multiple cores and pp into a multilayer board by high temperature and high pressure; use a CNC drill to drill through holes between different layers according to the customer's design.

[0029] In some optional embodiments, see Figure 4 , the post-process specifically includes: 410, molding process: milling the multi-layer board after the gold-plating process into single PCS or continuous circuit boards; 420, electrical testing process: conducting electrical conductivity test on the circuit board; 430, final inspection process: conducting final appearance inspection on the circuit board that has passed the electrical test, and screening out qualified circuit boards; 430, packaging process: packaging and shipping qualified circuit boards according to material numbers. In this embodiment, through steps 410-440, the multi-row production board is milled into a single PCS or a continuous shipping board to meet the customer's plug-in requirements; the electrical conductivity of the circuit board is tested; the appearance of the circuit board is finally inspected before the product is shipped; the PCB finished boards of different material numbers are classified and packaged for transportation and to avoid moisture absorption, etc., to meet customer needs.

[0030] Embodiment 2: According to another aspect of an embodiment of the present invention, a PCB board gold finger wiring device is provided, and the device is used to perform the above-mentioned PCB board gold finger wiring method to manufacture a printed circuit board. In this embodiment, the following steps are performed by the PCB board gold finger wiring device: Cutting: Cut the large-sized substrate into working size and process and bake it to prepare for the production of inner-layer circuits; Inner layer: make inner layer graphics and frame data; Lamination: According to the positioning holes of the inner layer, multiple core and PP sheets are pressed into a multi-layer board using high temperature and high pressure; Drilling: Use CNC drilling machines to drill through holes between different layers according to the customer's design; Electroplating: A copper layer of a certain thickness is generated in the hole and on the board surface through a replacement reaction to achieve the conduction function between different layers; Outer layer: Based on the outermost copper layer, the design pattern is transferred to the photosensitive film through exposure after lamination. After development, the photosensitive film that has not been photopolymerized is washed away to expose the copper surface, and then the copper exposed on the copper surface is etched away to form the required circuit pattern; Solder mask: In the design of circuit boards, some outer graphics require welding parts and bonding, while others do not. Ink is used to cover unnecessary areas to insulate and avoid short circuits between wires when welding parts, and to beautify the appearance. Text: Print various text symbols on the circuit board for easy identification; Metallization: At the customer's welding position, a nickel-gold layer with good oxidation resistance and welding effect is formed through replacement reaction; Molding: Milling and cutting multi-row production boards into single PCS or contiguous shipping boards to meet customer plug-in requirements; Electrical test: test the electrical conductivity of the circuit board; Final inspection: Final inspection of the appearance of the circuit board before the product is shipped; Packaging: PCB finished boards with different material numbers are packaged in different categories to facilitate transportation and avoid moisture absorption, etc., to meet customer needs.

[0031] Among them, only the gold fingers in the effective area are retained in the outer layer graphics, and the Dummy pad gold finger design in the ineffective area is removed to retain the signal transmission and driving power supply functions. The solder mask material is designed with a window for the gold fingers in the effective area, so that the nickel-gold layer can be formed normally in the post-process; the Dummy pad gold fingers in the ineffective area have been removed in the outer layer, and this place is lower than the effective area, so this position is designed with a non-window cover ink design to fill the low-lying area with ink to ensure that the board thickness is uniform and flat to meet the Bonding quality requirements. After verification, the Dummy pad gold finger design in the ineffective area of ​​the outer layer is removed, and the solder mask exposure material is designed with a non-window cover oil design. The thickness difference is 8.05um, which meets the customer's Bonding quality requirements and reduces the gold area by about 27%. The subsequent design of the gold finger wiring for the LCD optoelectronic panel can be designed in this way.

[0032] Embodiment 3: According to another aspect of the embodiment of the present invention, a printed circuit board is provided, characterized in that the printed circuit board is manufactured by performing the above-mentioned PCB board gold finger wiring method through the above-mentioned PCB board gold finger wiring device. In this embodiment, the present invention sequentially performs a dry film pressing process, an exposure process, a development process, and an etching process on the multilayer board through an outer layer process to form an outer layer circuit on the surface of the multilayer board; wherein the multilayer board includes an effective gold finger area and an invalid gold finger area, and the outer layer circuit includes an effective gold finger area; a copper layer of the effective gold finger area is manufactured; the present application performs a window opening process on the welding area of ​​the multilayer board through a solder mask process, and performs a solder mask process on other areas of the multilayer board except the welding area; wherein the welding area includes an effective gold finger area; an ink layer of the invalid gold finger area is manufactured. The effective gold finger area has the functional role of signal transmission and driving power supply; the invalid gold finger area plays a role of structural reinforcement and board surface flatness. The uniformity of the thickness of the gold finger of the photovoltaic board is guaranteed; the production cost is reduced, and the yield rate of the gold finger of the photovoltaic board is improved.

[0033] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. Similarly, in order to simplify the present invention and help understand one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, the various features of the embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. Wherein, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself is a separate embodiment of the present invention.

[0034] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and further may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive.

[0035] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present invention may be implemented with the aid of hardware comprising several different elements and with the aid of appropriately programmed computers. In a unit claim that lists several systems, several of these systems may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be understood as limitations on the order of execution.

Claims

1. A PCB board gold finger wiring method, characterized in that: The method comprises: The previous process is to manufacture a multilayer board and drill holes in the multilayer board; An electroplating process to form a copper layer of a preset thickness on the multilayer board; The outer layer process is to sequentially perform a dry film pressing process, an exposure process, a development process, and an etching process on the multilayer board to form an outer layer circuit on the surface of the multilayer board; wherein the multilayer board includes a valid gold finger area and an invalid gold finger area, and the outer layer circuit includes a valid gold finger area; A solder mask process, performing a window treatment on the soldering area of ​​the multilayer board, and performing a solder mask treatment on other areas of the multilayer board except the soldering area; wherein the soldering area includes an effective gold finger area; A gold deposition process to form a nickel-gold layer in the welding area through a replacement reaction; In the post-process, the multilayer board is formed, electrically tested, finally inspected and packaged.

2. A PCB board gold finger wiring method according to claim 1, characterized in that: The outer layer process specifically includes: Pressed dry film treatment: covering the surface of the copper layer with a photosensitive film; Exposure treatment: exposing the photosensitive film to UV light; Development process: dissolve the unpolymerized photosensitive film during the exposure process to expose the copper surface; Etching process: The copper layer exposed on the copper surface is etched away to form the outer layer circuit.

3. A PCB board gold finger wiring method according to claim 1, characterized in that: In the solder mask process, the invalid gold finger region is not subjected to window opening treatment, and the invalid gold finger region is subjected to solder mask treatment so that an ink layer is formed in the invalid gold finger region.

4. A PCB board gold finger wiring method according to claim 3, characterized in that: The thickness of the ink layer is higher than the thickness of the copper layer in the effective gold finger area.

5. A PCB board gold finger wiring method according to claim 3, characterized in that: The effective gold finger area and the invalid gold finger area are arranged alternately.

6. A PCB board gold finger wiring method according to claim 1, characterized in that: After the solder mask process and before the gold plating process, a text process is also included, and the text process specifically includes: printing text symbols for identification on the surface of the multilayer board.

7. A PCB board gold finger wiring method according to claim 1, characterized in that: The preceding process specifically includes: Cutting process: the substrate is cut into layers of preset size by a panel splitter, and the layers are baked; Inner layer process: according to the inner layer image and board frame data, the inner layer circuit is made on the layer board; Lamination process: according to the positioning holes of multiple layer boards, multiple layer boards are pressed together to form a multi-layer board at a preset temperature and a preset pressure; Drilling process: drilling via holes between different layers of the multilayer board by using a CNC drill.

8. A PCB board gold finger wiring method according to claim 1, characterized in that: The post-process specifically includes: Forming process: milling the multilayer board after the above-mentioned gold-plating process into single PCS or contiguous circuit boards; Electrical testing process: performing electrical continuity testing on the circuit board; Final inspection process: Conduct final appearance inspection on the circuit boards that have passed the electrical test to select qualified circuit boards; Packaging process: Qualified circuit boards are packaged and shipped according to the material number.

9. A PCB board gold finger wiring device, characterized in that: The device is used to execute the PCB board gold finger wiring method described in any one of claims 1-8 to manufacture a printed circuit board.

10. A printed circuit board, characterized in that: The printed circuit board is manufactured by executing the PCB board gold finger wiring method as described in any one of claims 1 to 8 through the PCB board gold finger wiring device as described in claim 9.

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