PCB fool-proof structure, PCB gold finger manufacturing method and device

Abstract

The embodiment of the present application relates to a PCB fool-proof structure, a PCB golden finger manufacturing method and device, and the present application sets the positioning area and the double-target area which are not communicated with each other, adopts the differential alignment mark in the multiple anti-soldering processes, effectively prevents the same material number from being misused in different processes, has the advantages of improving alignment accuracy, eliminating coverage deviation and improving product reliability.

Description

Technical Field

[0001] This invention relates to the field of PCB gold finger manufacturing technology, specifically to PCB foolproof structures, PCB gold finger manufacturing methods and apparatus. Background Technology

[0002] In PCB manufacturing, to achieve segmented and time-division contact during the insertion and removal of gold fingers, the gold fingers are often designed with varying lengths. This design requires the insulating properties of photocurable inks to cover and protect specific areas to be etched, preventing gold deposition during gold plating and ensuring the accuracy of subsequent etching processes. Therefore, such printed circuit boards require multiple solder mask processes during production.

[0003] Currently, the same set of alignment targets is used for alignment operations in multiple solder resist processes. However, existing target designs can only prevent mistakes in solder resist processes of different part numbers, versions, or facets, but cannot effectively distinguish the use of film between different production batches or different levels within the same part number and process. This deficiency leads to the risk of misuse of graphic films used at different stages of the same process in actual production, which may cause a series of quality problems such as coverage deviation, incorrect exposure or improper protection of gold finger areas, seriously affecting product reliability and yield.

[0004] Therefore, there is an urgent need for a more efficient and reliable error-proofing mechanism to improve the manufacturing precision and process stability of such special gold finger design products. Summary of the Invention

[0005] In view of the above problems, embodiments of the present invention provide a PCB error prevention structure, a PCB gold finger manufacturing method and apparatus, which are used to solve the problem that there is a risk of misuse of graphic films used in different stages of the same process in the prior art, which may cause a series of quality problems such as coverage deviation, incorrect exposure or improper protection of the gold finger area, which seriously affect product reliability and yield.

[0006] According to one aspect of the present invention, a PCB foolproof structure is provided, including a board edge component, a connector, and a plurality of target PCBs, wherein the target PCBs are fixed to a working board by the board edge component and / or the connector; The plate edge component is provided with a positioning area, a first target area and a second target area, and the positioning area, the first target area and the second target area are not connected to each other; the positioning area is provided with a positioning hole, the first target area is provided with a first target and the second target area is provided with a second target.

[0007] In some alternative embodiments, the plate edge member includes a first plate edge, a second plate edge, a third plate edge, and a fourth plate edge, which are connected end to end to form a closed frame.

[0008] In some optional embodiments, the positioning area is disposed on the first plate edge and the third plate edge; the first target area is disposed on the first plate edge, the second plate edge, the third plate edge and the fourth plate edge; and the second target area is disposed on the first plate edge, the second plate edge, the third plate edge and the fourth plate edge.

[0009] According to another aspect of the present invention, a method for manufacturing PCB gold fingers is provided, the method comprising: The preceding process is used to manufacture the above-mentioned PCB foolproof structure, wherein the target PCB board of the PCB foolproof structure has a first gold finger area, a second gold finger area and a non-gold finger area. The solder resist process involves selecting a first film data based on a first target to perform solder resist treatment on the PCB anti-foolproof structure, so as to form a first solder resist layer on the surface of the non-gold finger area. In the first selective ink printing process, the second film data is selected according to the second target to print selective ink on the first gold finger area, so that the first gold finger area forms a first selective ink layer; The gold plating process involves plating gold in the second gold finger area to form a first gold plating layer; The first film removal process removes the first selective oil layer in the first gold finger area; In the second selective ink printing process, the selective ink is printed on the second gold finger area according to the third film data selected based on the first target, so that the second gold finger area forms a second selective ink layer. The outer layer etching lead process removes the copper plating layer in the first gold finger area; The second film removal process removes the second selective oil layer in the second gold finger area.

[0010] In some optional embodiments, during the solder resist process, after the PCB anti-foolproof structure is positioned by the positioning holes, during the solder resist ink application, a screen blocking point is added to the position of the first target, and ink covering is performed on the second target so that the first target serves as the alignment target. The first film data is then aligned with the first target to perform solder resist treatment on the PCB anti-foolproof structure.

[0011] In some optional embodiments, during the solder resist process, in the first ink-selection printing process, after the PCB anti-foolproof structure is positioned by the positioning holes, during the ink-selection process, a screen blocking point is added to the position of the second target, and ink covering is performed on the first target so that the second target serves as the alignment target. The second film data is then aligned with the second target to perform ink-selection printing on the PCB anti-foolproof structure.

[0012] In some alternative implementations, during the solder resist process, in the second ink-selection printing process, after the PCB anti-foolproof structure is positioned by the positioning holes, during the ink-selection process, a screen blocking point is added to the position of the first target, and ink covering is performed on the second target so that the first target serves as the alignment target. The third film data is then aligned with the first target to perform ink-selection printing on the PCB anti-foolproof structure.

[0013] In some alternative implementations, the process includes the following steps after the solder resist process and before the first selective ink printing process: The text processing involves printing text on the first solder resist layer to form the first text layer.

[0014] In some alternative implementations, after the second film removal process, the following steps are also included: In the text printing process, a third layer of selective ink is formed by printing selective ink on the first text layer. In the chemical gold plating process, a second gold plating layer is formed on the solder pads in the non-gold finger area by chemical deposition; The film removal process removes the third selective oil layer from the PCB foolproof structure.

[0015] According to another aspect of the present invention, a PCB gold finger manufacturing apparatus is provided, the apparatus being used to perform the above-described PCB gold finger manufacturing method to manufacture a printed circuit board.

[0016] The PCB error-proof structure, PCB gold finger manufacturing method, and apparatus of the present invention have the following advantages: The PCB error-proof structure of the present invention includes a board edge component, a connector, and multiple target PCB boards. The target PCB boards are fixed to a working board by the board edge component and / or the connector. The board edge component is provided with a positioning area, a first target area, and a second target area, and the positioning area, the first target area, and the second target area are not connected to each other. The positioning area has a positioning hole, the first target area is provided with a first target, and the second target area is provided with a second target. By setting up non-connected positioning areas and dual target areas, the present invention uses differentiated alignment marks in multiple solder mask processes, effectively preventing the misuse of films for different processes of the same part number, and has the advantages of improving alignment accuracy, eliminating coverage deviation, and improving product reliability.

[0017] The above description is merely an overview of the technical solutions of the embodiments of the present invention. In order to better understand the technical means of the embodiments of the present invention and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0018] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic diagram of the PCB error-proof structure of Embodiment 1 provided by the present invention is shown; Figure 2 A partial schematic diagram of the PCB error-proof structure of Embodiment 1 provided by the present invention is shown; Figure 3 A flowchart illustrating the PCB gold finger fabrication method of Embodiment 2 provided by the present invention is shown; Figure 4 The diagram shows a process flow diagram of Embodiment 2 provided by the present invention after the second film removal process. Attached image description: 10. Plate edge component; 11. First plate edge; 12. Fourth plate edge; 13. Positioning hole; 14. First target; 15. Second target; 20. Target PCB board; 30. Connectors. Detailed Implementation

[0020] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0021] Example 1: Figure 1 An embodiment of the PCB error prevention structure of the present invention is shown to solve the problem that there is a risk of misuse of graphic films used in different stages of the same process in the prior art, which may cause a series of quality problems such as coverage deviation, incorrect exposure or improper protection of gold finger areas, which seriously affect product reliability and yield.

[0022] Specifically, the PCB anti-foolproof structure includes a board edge component 10, a connector 30, and multiple target PCB boards 20. The board edge component is provided with a positioning area, a first target area, and a second target area that are not connected to each other. The positioning area has a positioning hole 13, the first target area is provided with a first target 14, and the second target area is provided with a second target 15.

[0023] In this embodiment, the board edge component refers to the edge component that carries the positioning and identification functions. Specifically, it can be made of FR-4 material and formed into a closed frame structure through milling. The positioning area refers to the spatial position used to fix the PCB board. Specifically, it can use a circular hole structure with a diameter of 0.5mm to 1.5mm, and achieve mechanical positioning with a pin and the work board. The first target area refers to the functional area that carries the alignment mark of the first process. Specifically, it can use a cross-shaped pattern formed by copper foil etching, and its size can be controlled within the range of 3mm × 3mm. The second target area refers to the functional area that carries the alignment mark of the second process. Specifically, it can use a ring-shaped copper foil structure, with the inner diameter nested with the outer diameter of the cross-shaped target.

[0024] Specifically, the target PCB board is rigidly connected to the board edge components via connectors, forming a stable assembly structure on the work board. After coarse positioning is achieved by the positioning holes and the work board positioning pins, the first target is aligned with the film data of the solder resist process, and the second target is aligned with the film data of the ink selection printing process. Due to the physical isolation of the three functional areas, the stencil blocking points of the solder resist process can cover the area of ​​the second target, while the stencil blocking points of the ink selection process can cover the area of ​​the first target, forming physical mis-detection between processes. For example, in the gold plating process, after the second target is covered with ink, only the first target is retained as a valid alignment mark, thereby avoiding the confusion between the gold plating film and the solder resist film.

[0025] Compared with existing technologies, traditional solutions using only a single target area result in overlapping alignment markers across different processes. This invention addresses this by establishing independent first and second target areas, allowing the solder resist process and the chemical oil selection process to correspond to different alignment markers. This spatial separation design avoids misidentification of targets caused by incomplete coverage of the stencil, while also achieving logical interlocking between processes through variations in target combinations.

[0026] Through the above technical solution, the present invention can effectively prevent the misuse of film data from different processes in the same manufacturing process, and ensure accurate coverage of the solder resist layer and the selective oil layer. Specifically, the gold deposition in non-target areas during the gold plating process is effectively suppressed, and the circuit forming accuracy of the outer layer etching lead process is improved, thereby reducing the risk of short circuits in the gold fingers and improving product reliability.

[0027] In some alternative embodiments, the present invention proposes that the plate edge component includes a first plate edge 11, a second plate edge, a third plate edge, and a fourth plate edge 12, which are connected end to end to form a closed frame.

[0028] The closed frame refers to a ring structure formed by connecting four plates in sequence. It can be implemented using a rectangular or square frame structure, and the four plates are fixed at the joints by right-angle bends or welding. The first, second, third, and fourth plates refer to the four sides of the closed frame, which can be made of metal plates or composite material plates of equal or unequal length, and the width of each plate can be 5-20mm.

[0029] Specifically, the closed frame forms a rigid support structure through its four interconnected edges, and the target PCB board is fixed inside the closed frame using connectors. The four edges of the closed frame provide mounting bases for the positioning area, the first target area, and the second target area. For example, positioning holes can be set on the first and third edges, and first and second targets are set on all four edges. The closed structure of the frame ensures that the positioning areas and target areas on each edge are spatially symmetrically distributed, allowing for positioning and alignment through any adjacent edges during the solder mask process.

[0030] Compared with existing technologies, the edge components of the present invention typically employ non-closed L-shaped or U-shaped structures, which can only provide single-sided or double-sided positioning references, resulting in limited target area distribution. In contrast, the closed frame, through its ring structure, enables all four edges of the plate to have positioning and alignment functions, accommodating the alignment requirements of film data in different processes and avoiding film misuse problems caused by insufficient target area.

[0031] Through the above technical solution, this invention solves the problem of insufficient alignment references for film data at different stages of the same process in the prior art. The closed frame provides multiple sets of target areas through the four board edges, allowing the solder resist process and the chemical ink printing process to use targets on different board edges for alignment, thereby eliminating the risk of film data misuse and ensuring the coverage accuracy of the gold finger area and non-gold finger area.

[0032] In some optional embodiments, the present invention proposes that the plate edge component includes a first plate edge, a second plate edge, a third plate edge, and a fourth plate edge, the first plate edge, the second plate edge, the third plate edge, and the fourth plate edge are connected end to end to form a closed frame, a positioning area is disposed on the first plate edge and the third plate edge, a first target area is disposed on the first plate edge, the second plate edge, the third plate edge, and the fourth plate edge, and a second target area is disposed on the first plate edge, the second plate edge, the third plate edge, and the fourth plate edge.

[0033] The positioning area refers to the area used to fix the relative position of the PCB board and the working board. Specifically, it can be achieved by opening positioning holes on the edges of the first and third boards, and completing the physical positioning by cooperating with mechanical fixtures and positioning holes.

[0034] The first target area refers to the marking area used as the alignment reference in the solder resist process. Specifically, it can be achieved by setting a cross-shaped or circular copper foil pattern on the edge of the first to the fourth plate. The image alignment is completed by capturing the target position through an optical recognition device.

[0035] The second target area refers to the marking area used as the alignment reference in the ink printing process. Specifically, it can be achieved by setting a diamond or square copper foil pattern on the edge of the first plate to the edge of the fourth plate, and completing the printing positioning by matching the screen blocking point with the target position.

[0036] Specifically, the closed frame forms a rigid support structure through its four edges, and the asymmetrical distribution of positioning holes on the first and third edges prevents reverse installation. The full coverage of the first and second target areas on all four edges allows for alignment of targets on any edge according to process requirements in different processes. For example, in the anti-welding process, the first target on the first edge can be used as a reference, and in the chemical oil selection process, the second target on the second edge can be used as a reference. Thus, precise differentiation of film data can be achieved at different production stages for the same part number using targets in different positions.

[0037] Compared with existing technologies, traditional solutions only set a single target group on the same plate edge, resulting in overlapping alignment references for different processes. This invention, however, sets positioning areas and two types of target areas on four plate edges respectively, allowing each process to independently utilize targets on different plate edges, thus avoiding film misuse problems caused by target reuse.

[0038] Through the above technical solution, the present invention enables the independent alignment of targets on different sides of the same PCB board at different process stages, effectively preventing the confusion of film data in the solder mask and chemical oil selection processes, reducing the risk of gold finger area protection failure, and improving the yield of segmented gold plating process.

[0039] Example 2: Figure 3 An embodiment of the PCB gold finger manufacturing method of the present invention is shown. The PCB gold finger manufacturing method specifically includes: 310, Pre-process, used to fabricate the PCB foolproof structure of Example 1, wherein the target PCB board of the PCB foolproof structure has a first gold finger area, a second gold finger area and a non-gold finger area; in step 310, the pre-process refers to preparing a foolproof PCB substrate with a specific gold finger area through lamination, drilling and circuit pattern transfer processes. Specifically, laser cutting or mechanical stamping can be used to separate the target PCB board from the board edge components, providing physical support for subsequent processes.

[0040] 320, Solder resist process: Select the first film data according to the first target to perform solder resist treatment on the PCB anti-foolproof structure so that a first solder resist layer is formed on the surface of the non-gold finger area; In step 320, the solder resist process refers to forming an insulating protective layer in the non-gold finger area through an exposure and development process. Specifically, liquid photosensitive solder resist ink can be applied and then patterned using the first film data to prevent the gold plating layer from depositing in the non-target area.

[0041] 330, the first selective ink printing process, selects the second film data according to the second target and prints selective ink on the first gold finger area so that the first gold finger area forms a first selective ink layer; in step 330, the selective ink printing process refers to transferring the resist ink to the target area through screen printing, specifically, a metal screen can be used in conjunction with the second film data to cover the first gold finger area during the first printing.

[0042] 340, Gold plating process, gold plating is performed in the second gold finger area to form a first gold plating layer; in step 340, the gold plating process refers to forming a conductive layer on the exposed metal surface by electrochemical deposition. Specifically, a pulse electroplating device can be used to deposit a nickel-gold alloy layer in the second gold finger area to improve the wear resistance and conductivity of the contact area.

[0043] 350, the first film removal process, removes the first selective oil layer in the first gold finger area; in step 350, the first selective oil layer printed with the first selective oil is removed by selective oil removal solution.

[0044] 360, the second selective ink printing process, selects the third film data according to the first target to print selective ink on the second gold finger area so that the second gold finger area forms a second selective ink layer; in step 350, the selective ink printing process refers to transferring the resist ink to the target area by screen printing, specifically, a metal screen can be used in conjunction with the second film data to cover the second gold finger area during the second printing.

[0045] 370, outer layer etching lead process, etching to remove the copper plating layer of the first gold finger area; in step 370, the copper plating layer of the first gold finger area is removed by etching solution.

[0046] 380, Second film removal process, removing the second selective oil layer in the second gold finger area. In step 350, the second selective oil layer printed with the second selective oil is removed by selective oil removal solution.

[0047] Specifically, after the substrate is fabricated in the previous process, the PCB anti-mistake structure undergoes a solder mask process. A first target is aligned with the first film data to cover the non-gold finger areas with the solder mask layer. Then, in the first selective solder mask printing process, a second target is aligned with the second film data, covering only the first gold finger area with the selective solder mask layer. At this point, the second gold finger area remains exposed, and gold is plated onto this area during the gold plating process. After gold plating, the selective solder mask layer in the first gold finger area is removed through a stripping process, exposing the copper layer in that area. Next, in the second selective solder mask printing process, the first target is re-aligned with the third film data to cover the second gold finger area with the selective solder mask layer, protecting its gold layer from subsequent etching. In the outer layer etching lead process, the copper layer in the first gold finger area is etched away. Finally, a second stripping process removes all the selective solder mask layer, forming the finished product with a segmented gold finger structure.

[0048] Compared to existing technologies, conventional solder resist processes use a single target to align film data from different stages, which can easily lead to misuse of film data from different stages of the same process. This method, however, alternates between using a first target and a second target for the solder resist process and the two degreasing processes respectively, ensuring that the alignment references for different processes are independent. For example, in the first degreasing process, the second target, as the alignment reference, avoids confusion with the first target used in the solder resist process, thereby ensuring accurate matching of film data for each process.

[0049] Through the above technical solution, this invention effectively solves the problem of coverage deviation caused by misuse of film data at different stages of the same process. By differentiating the correspondence between the target and the film data, the coverage areas of the solder resist layer and the selective oil layer are strictly limited within the target range, avoiding incorrect exposure or protection failure of the gold finger area. At the same time, alternating the use of different targets in the two selective oil processes can eliminate the accumulation of positioning errors caused by repeated use of targets, improving the processing accuracy of the segmented structure of the gold finger.

[0050] In some alternative embodiments, the present invention proposes that, in the solder resist process, after the PCB anti-foolproof structure is positioned by the positioning holes, during the solder resist ink application, a screen blocking point is added to the position of the first target, and ink covering treatment is performed on the second target so that the first target serves as the alignment target, and the first film data is aligned with the first target to perform solder resist treatment on the PCB anti-foolproof structure.

[0051] In this embodiment, positioning holes refer to mechanical positioning structures provided on the board edge components. Specifically, they can be implemented using circular through holes with a diameter ranging from 0.5 to 2.0 mm, used for physical positioning of the PCB board during the solder resist process. Screen printing baffles refer to barrier structures covering specific locations on the screen printing stencil. Specifically, they can be formed by stacking polyimide films with a thickness of 10-50 μm, used to prevent ink deposition in the target area. Ink covering treatment refers to the operation of pre-coating the target surface with solder resist ink. Specifically, liquid photosensitive ink with a viscosity range of 100-200 Pa·s can be used for coating, used to protect the target area from the influence of subsequent processes.

[0052] Specifically, during the solder mask process, the PCB's foolproof structure is fixed by engaging with the positioning pins of the production equipment through positioning holes. Solder mask ink is applied using a printing screen with screen dotted dots, which cover the corresponding positions of the first target, preventing ink deposition in that area and creating an exposed target pattern. Simultaneously, the second target area is completely covered by ink through a capping process, eliminating its interference with subsequent processes. The first film data is then aligned with the exposed first target using an optical alignment system to ensure the correspondence between the solder mask pattern and the gold finger area.

[0053] Compared with existing technologies, traditional solder resist processes rely on the same set of targets for alignment across all steps, making it impossible to effectively distinguish film data from different steps using the targets. This invention differentiates two sets of targets in different steps, ensuring that the first target serves only as an effective alignment marker in the solder resist process, while the second target, covered by ink, cannot participate in alignment. This physically prevents the risk of mixing film data between different steps.

[0054] Through the above technical solution, this invention achieves a unique match between film data and the target in the solder resist process, avoiding pattern misalignment caused by the repeated use of the same target. The coverage accuracy of the solder resist ink in the gold finger area is improved, the probability of false exposure in non-target areas and gold finger protection failure is significantly reduced, and the stability of the production process is enhanced.

[0055] In some alternative embodiments, the present invention proposes that in the first ink-selective printing process, after the PCB anti-foolproof structure is positioned by the positioning hole, during the ink-selective printing process, a screen blocking point is added to the position of the second target, and ink covering treatment is performed on the first target so that the second target serves as the alignment target. The second film data is then aligned with the second target to perform ink-selective printing on the PCB anti-foolproof structure.

[0056] In this embodiment, positioning holes refer to through-hole structures set on the board edge components, which can be implemented using mechanical punching or laser drilling processes, and are used to achieve precise positioning of the PCB board during the printing process. Screen blocking points refer to barrier structures set on the printing screen, which can be implemented using metal mesh or polyester screen material, and are used to prevent ink deposition in the second target area. Ink covering treatment refers to covering the surface of the first target with solder resist ink, which can be implemented using screen printing or inkjet coating processes, and is used to eliminate interference from the first target in this process. The second target refers to geometric marks set on the board edge components, which can be implemented using copper foil etching or ink printing methods, and are used as alignment references for the selective ink printing process. The second film data refers to a data file containing the selective ink printing pattern, which can be implemented using Gerber format or ODB++ format, and is used to control the pattern distribution of the selective ink layer.

[0057] Specifically, during the first selective ink printing process, the PCB's anti-foolproof structure is physically fixed by engaging the positioning pins of the printing equipment through positioning holes. Screen stops are set on the printing screen corresponding to the second target position to prevent the selective ink from depositing in that area. Simultaneously, the first target area is covered with ink during screen design. When the second film data is loaded onto the printing equipment, the optical alignment system identifies the geometric features of the second target to achieve precise alignment between the printing screen and the PCB board. At this point, the second target serves as the sole effective alignment reference, ensuring that the selective ink forms a predetermined pattern ink layer only in the first gold finger area.

[0058] Compared with existing technologies, traditional methods use the same set of targets for alignment in multiple solder resist processes. This invention, however, creatively uses a second target as the alignment reference in the initial chemical ink printing process. The risk of film misuse due to target reuse in existing technologies is effectively eliminated. By employing different targets in different processes, each process stage has an independent and identifiable alignment marker, thus preventing the possibility of misuse of graphic film.

[0059] Through the above technical solution, this invention achieves independent alignment control of the selective ink printing process, effectively preventing the misuse of film data between different processes. The alignment accuracy between the printing screen and the PCB board is improved, and the selective ink layer can accurately cover the predetermined area, avoiding incorrect exposure of the gold finger area during the gold plating process, and significantly improving the product qualification rate.

[0060] In some alternative embodiments, the present invention proposes that in the second ink-selection printing process, after the PCB anti-foolproof structure is positioned by the positioning holes, during the ink-selection process, a screen blocking point is added to the position of the first target, and ink covering is performed on the second target so that the first target serves as the alignment target. The third film data is then aligned with the first target to perform ink-selection processing on the PCB anti-foolproof structure.

[0061] In this embodiment, positioning holes refer to reference holes used to fix the relative position of the PCB anti-foolproof structure and the processing equipment. These can be achieved through mechanical punching or laser drilling, with physical positioning achieved through the cooperation of the holes and the equipment positioning pins. Screen blocking points refer to barrier structures covering specific areas of the screen, which can be implemented using metal sheets or polymer material patches, used to prevent ink from flowing into the corresponding areas. Ink covering treatment refers to pre-covering a protective layer on the surface of the second target, which can be implemented using photocurable ink or high-temperature resistant adhesive film, used to prevent ink from contacting the target surface. Third film data refers to the exposed film containing the graphic information of the second selective ink printing, which can be implemented using high-resolution photoplotting film, used to form the pattern of the second selective ink layer in the second selective ink printing process.

[0062] Specifically, in the second ink-selective printing process, after the PCB foolproof structure completes mechanical positioning through the positioning holes, the screen blocking points are set at the positions corresponding to the first target to prevent ink from covering that area. Simultaneously, the surface of the second target is completely covered by the ink layer, preventing it from participating in alignment identification. At this point, the first target serves as the only valid alignment marker, undergoing optical alignment calibration with the third film data. After alignment is completed, the ink is precisely coated onto the second gold finger area through the screen opening area, forming the second ink-selective layer.

[0063] Compared with existing technologies, which use the same set of targets for alignment in multiple solder resist processes, this invention addresses the risk of misuse of film data across different processes. This invention selects different targets as alignment benchmarks in stages, forcing the use of the first target and shielding the second target during the second chemical ink printing process. This creates an irreversible process identification mechanism, physically eliminating film data confusion.

[0064] Through the above technical solution, this invention establishes target selection rules in multiple solder resist processes. By physically isolating the target through masking and activation, it ensures that different processes must match the corresponding film data. This mechanism effectively prevents pattern offset or overlay errors caused by misuse of film at different stages in the same process, improving the protection accuracy of the gold finger area.

[0065] In some alternative embodiments, the present invention proposes to include a text process after the solder resist process and before the first selective ink printing process, wherein text is printed on the first solder resist layer to form a first text layer.

[0066] In this embodiment, the text processing step refers to the step of printing identification information on the surface of the non-gold finger area after solder resist treatment. Specifically, screen printing or inkjet printing technology can be used to attach ink to the surface of the solder resist layer to form a marking layer containing product model, batch number, or process parameters. This process provides a physical reference for subsequent processes by establishing a visual information carrier. The first text layer refers to the cured ink layer covering the surface of the solder resist layer, which can be formed by curing high-temperature resistant epoxy resin ink with ultraviolet light. This structural layer retains the solder resist protection function while enabling rapid identification of different process stages through specific text patterns.

[0067] Specifically, after the solder resist process is completed, the work plate is fixed through positioning holes and then enters the text printing station. Ink is precisely transferred to the designated area of ​​the first solder resist layer using screen printing equipment, and after curing, text with a raised or recessed structure is formed. This text layer serves as a physical positioning reference in the subsequent ink-selective printing process, with its edge contours spatially corresponding to the alignment marks on the film data. Before the first ink-selective printing process, operators can use optical inspection equipment to read the process parameters contained in the text layer to ensure that the selected second film data matches the current production stage.

[0068] Compared with existing technologies, traditional processes directly proceed to ink printing after solder resist treatment, lacking a physical verification step in the intermediate process. This solution, by adding a structured identification layer formed by the text process, constructs a physical verification mechanism for process connection, effectively preventing the risk of mixing film data from different production batches.

[0069] Through the above technical solution, this invention achieves precise matching between the graphic film and the process stage during production, avoiding coverage deviations caused by film misuse. The process parameters contained in the text layer can directly guide operators to select the correct second film data, ensuring the positioning accuracy of the first gold finger area for ink printing. This structured identification layer can also serve as a physical basis for quality traceability in subsequent etching processes, improving the efficiency of troubleshooting anomalies.

[0070] In some alternative implementations, see [link to implementation details]. Figure 4 The present invention proposes that after the second film removal process, it further includes: 410, Text printing selective ink process, printing selective ink on the first text layer to form a third selective ink layer; 420, Chemical gold plating process, forming a second gold plating layer on the solder pads in non-gold finger areas through chemical deposition; 430, Film Removal Process: Removes the third selective oil layer from the PCB's anti-foolproof structure.

[0071] In steps 410-430, the text printing chemical ink process refers to the operation of forming a coating layer on the surface of the first text layer using chemical ink. This can be achieved using screen printing or inkjet printing equipment, and is used to protect the text layer from chemical deposition during the chemical gold plating process. The chemical gold plating process refers to the process of forming a metallic plating layer on the surface of the pads in the non-gold finger areas through chemical deposition. This can be achieved using a chemical gold plating solution at room temperature, and is used to enhance the conductivity and oxidation resistance of the pads. The film removal process refers to the step of removing the third chemical ink layer by dissolving or peeling, and can be achieved by immersion in an alkaline solution or rinsing with an organic solvent, and is used to restore the surface condition of the non-gold finger areas.

[0072] Specifically, after etching the gold plating layer in the second gold finger area, the PCB's anti-foolproof structure is fixed to the printing equipment through positioning holes. Then, a third film is used to print the first text layer using selective ink. For example, during screen printing, the screen blocking dots are set at the first target position to precisely cover the text area, forming a third selective ink layer with a thickness of 10-20 μm. Subsequently, the PCB is immersed in a chemical gold plating solution. A gold layer with a thickness of 0.05-0.2 μm is deposited on the copper pads in the non-gold finger areas, while the selective ink-covered areas completely block the gold plating reaction. Finally, the third selective ink layer is removed by immersion in a 5% sodium hydroxide solution, creating a clear interface between the text layer and the gold-plated pads.

[0073] In some specific embodiments, the third chemical oil layer can be a UV-curable ink, which forms a precise pattern through exposure and development; the chemical gold plating solution can be a citric acid system solution with a pH of 8.5-9.5, and the deposition rate is controlled at 0.01-0.03 μm per minute; a high-pressure spraying device can be used in the film removal process to improve the ink stripping efficiency.

[0074] Compared with existing technologies, current single-pass solder resist processes cannot selectively protect non-gold finger areas during the electroless gold plating stage, resulting in deviations in the gold layer deposition position on the solder pad surface. This solution implements selective solder resist printing and film removal operations in stages, establishing a temporary protective layer before the electroless gold plating process. This not only prevents metal deposition in non-target areas but also achieves precise removal of different functional layers through two independent film removal steps.

[0075] Through the above technical solution, this invention effectively solves the problem of film misuse between different processes in the same manufacturing process. By establishing and removing the protective layer step by step, it ensures that the pads in non-gold finger areas are only exposed in the target area during the gold plating stage. This process avoids abnormal pad conductivity caused by incorrect gold layer coverage. At the same time, by coordinating the timing of the gold plating and gold plating processes, the text layer protection and pad processing are separated, significantly improving the accuracy of gold plating position and product reliability.

[0076] Example 3: Based on Embodiment 1 or Embodiment 2, the present invention proposes a PCB gold finger manufacturing apparatus. This apparatus is used to perform a manufacturing method including a solder resist process, a chemical ink printing process, a gold plating process, and a film removal process to manufacture a printed circuit board with a segmented gold finger structure.

[0077] In this embodiment, the PCB gold finger fabrication device refers to an automated device capable of performing multiple solder resist and selective ink printing processes. Specifically, it can be implemented using an integrated system with a positioning module, a target recognition module, and a printing control module. The positioning module mechanically engages with the work board through positioning holes to ensure the positional accuracy of the PCB board during processing. The target recognition module captures image information of the first and second targets using optical sensors and switches the alignment reference according to different processes. The printing control module retrieves the corresponding film data based on the target recognition results and drives the screen to perform ink application or ink covering actions.

[0078] Specifically, after the PCB board is fixed through positioning holes during the solder mask process, the target recognition module selects either a first or second target as the alignment reference according to a preset program. For example, during the first selection of chemical ink printing, the second target is recognized and triggers the screen dot adjustment, while the first target area is covered with ink, thus ensuring precise matching between the second film data and the target area. After the gold plating process is completed, the device switches to the outer layer etching lead process. At this time, the target recognition module recalls the first target as the reference again, driving the third film data to align with the second gold finger area. The switching between each process is completed automatically by the control module, avoiding the risk of film misuse due to manual intervention.

[0079] Compared to existing technologies, which rely on a single target for multiple solder mask alignments, this invention addresses the issue of misuse of film in different stages of the same manufacturing process. This device dynamically switches alignment references via a target recognition module, and combines this with coordinated control of stencil blocking points and ink coverage, enabling precise matching of corresponding film data for PCBs of the same part number at different production stages. This design effectively solves the problem of film misuse within the same process, while eliminating the need for additional error-proofing markings and simplifying the production flow.

[0080] Through the above technical solution, this invention ensures accurate retrieval of film data during multiple solder resist and chemical ink printing processes, avoiding coverage deviations or exposure of the gold finger area due to alignment errors. This device, through automated target recognition and process switching mechanisms, significantly improves the processing accuracy of segmented gold finger structures while reducing quality defects caused by film misuse, thereby improving product yield and reliability.

[0081] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. Similarly, for the sake of brevity and to aid in understanding one or more aspects of the invention, in the description of exemplary embodiments of the invention above, various features of the embodiments are sometimes grouped together in a single embodiment, figure, or description thereof. The claims, which follow the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0082] Those skilled in the art will understand that the modules in the device of the embodiment can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiment can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components, except that at least some of such features and / or processes or units are mutually exclusive.

[0083] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several systems, several of these systems may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A method for manufacturing PCB gold fingers, characterized in that, The method includes: The preceding process is used to manufacture a PCB error-proof structure. The target PCB board of the error-proof structure has a first gold finger area, a second gold finger area, and a non-gold finger area. The error-proof structure includes a board edge component, a connector, and multiple target PCB boards. The target PCB boards are fixed to a work board via the board edge component and / or the connector. The board edge component has a positioning area, a first target area, and a second target area, and these areas are not connected. The positioning area has a positioning hole, the first target area has a first target, and the second target area has a second target. The board edge component includes a first board edge, a second board edge, a third board edge, and a fourth board edge, which are connected end-to-end to form a closed frame. The positioning area is located on the first and third board edges, the first target area is located on the first, second, third, and fourth board edges, and the second target area is located on the first, second, third, and fourth board edges. The solder resist process involves selecting a first film data based on a first target to perform solder resist treatment on the PCB anti-foolproof structure, so as to form a first solder resist layer on the surface of the non-gold finger area. In the first selective ink printing process, the second film data is selected according to the second target to print selective ink on the first gold finger area, so that the first gold finger area forms a first selective ink layer; The gold plating process involves plating gold in the second gold finger area to form a first gold plating layer; The first film removal process removes the first selective oil layer in the first gold finger area; In the second selective ink printing process, the selective ink is printed on the second gold finger area according to the third film data selected based on the first target, so that the second gold finger area forms a second selective ink layer. The outer layer etching lead process removes the copper plating layer in the first gold finger area; The second film removal process removes the second selective oil layer in the second gold finger area.

2. The PCB gold finger manufacturing method according to claim 1, characterized in that, In the solder resist process, after the PCB anti-foolproof structure is positioned through the positioning holes, during the solder resist ink application, a screen blocking point is added to the position of the first target, and ink covering is performed on the second target so that the first target serves as the alignment target. The first film data is then aligned with the first target to perform solder resist treatment on the PCB anti-foolproof structure.

3. The PCB gold finger manufacturing method according to claim 1, characterized in that, In the solder resist process, during the first chemical ink printing process, after the PCB anti-foolproof structure is positioned through the positioning holes, when the chemical ink is applied, a screen blocking point is added to the position of the second target, and ink covering is performed on the first target so that the second target serves as the alignment target. The second film data is then aligned with the second target to perform chemical ink printing on the PCB anti-foolproof structure.

4. The PCB gold finger manufacturing method according to claim 1, characterized in that, In the solder resist process, in the second ink selection printing process, after the PCB anti-foolproof structure is positioned by the positioning holes, when the ink is applied to the first target, a screen blocking point is added to the first target position, and ink covering is performed on the second target so that the first target serves as the alignment target. The third film data is then aligned with the first target to perform ink selection printing on the PCB anti-foolproof structure.

5. The PCB gold finger manufacturing method according to claim 4, characterized in that, The process includes the steps following the solder resist process and the first chemical ink printing process; The text processing involves printing text on the first solder resist layer to form the first text layer.

6. The PCB gold finger manufacturing method according to claim 5, characterized in that, Following the second film removal process, the following steps are also included: In the text printing process, a third layer of selective ink is formed by printing selective ink on the first text layer. In the chemical gold plating process, a second gold plating layer is formed on the solder pads in the non-gold finger area by chemical deposition; The film removal process removes the third selective oil layer from the PCB foolproof structure.

7. A PCB gold finger manufacturing apparatus, characterized in that, The apparatus is used to perform the PCB gold finger manufacturing method according to any one of claims 1-6 to manufacture a printed circuit board.

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