A PCB substrate electroplating repair method

Abstract

The present invention provides a PCB substrate electroplating repair method, which cleans defective points by mixing a certain proportion of liquid medicine, adds liquid medicine to a special fixture for repair, and repairs the defective points by electroplating. Compared with manual repair methods of removing residual copper and welding, it is simpler and has low requirements for operators, which is beneficial to reducing labor costs. Compared with manual repair, it greatly reduces time costs, and increases the profits of circuit board manufacturing factories.

Description

Technical Field

[0001] The invention relates to the technical field of PCB repair, and in particular to a PCB substrate electroplating repair method. Background Art

[0002] Printed circuit boards (PCBs), also known as printed circuit boards, are providers of electrical connections for electronic components. Functional defects may occur during the manufacturing process of circuit boards, such as broken wires / large area missing. The current repair method is to repair them manually through welding technology, using a correction knife to manually remove the residual copper, and then re-welding the damaged position by welding. This method has extremely high requirements for personnel. When removing the residual copper, it is necessary to use just the right correction tool and force to correct it to avoid damage to other areas on the edge of the residual copper during the correction process. In addition, the current PCB boards are becoming more and more high-precision and high-density. Manual operation has limitations in accuracy and repairability. Repair consumes a lot of manual energy and increases the cost of repair.

[0003] In addition to removing residual copper, the current method of electroplating repair is through manual welding, which also has certain requirements for personnel and requires operators to be highly focused, otherwise wrong soldering is likely to occur, thus affecting the function and performance of the circuit board. Not only is the operation difficult but it also consumes a long time. Summary of the invention

[0004] The object of the present invention is to provide a PCB substrate electroplating repair method that can quickly repair a circuit board and increase the profits of a circuit board manufacturing factory, thereby solving the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions.

[0006] A PCB substrate electroplating repair method, characterized in that the method steps are as follows:

[0007] S1: Clean the defective area of ​​the PCB substrate with 3% to 5% sulfuric acid, and then clean it with pure water to remove the oxide layer and dirt in the defective area;

[0008] S2: Confirm the size of the points on the PCB substrate that need to be repaired, select the corresponding opening tape for pasting, paste two layers in total, and compact the tape to prevent gaps from leaking out and contaminating the board surface;

[0009] S3: Clean the opening of the tape with pure water, and then dry it with a dryer;

[0010] S4: Apply catalyst to the opening of the tape and the defect;

[0011] S5: Apply accelerator to the opening of the tape and the defect, and dry it with a dryer;

[0012] S6: Clean the opening of the tape with pure water and dry it with a dryer;

[0013] S7: remove the first layer of tape;

[0014] S8: Fit the part of the PCB substrate that needs to be repaired to the bottom of the pen plating jig, and drip pen plating liquid from the opening of the pen plating jig;

[0015] S9: Connect the positive pole of the pen plating jig to the copper foil, and the negative pole to the negative pole of the pen plating jig. Start the small motor to vibrate the pen plating liquid to ensure the activity of the pen plating liquid. Turn on the power for electroplating repair for 20 to 40 minutes.

[0016] S10: After the electroplating is completed, the excess solution is absorbed, the excess tape is torn off, and then the inspection is carried out, the protruding parts are polished, and the excess copper is burned off by laser.

[0017] Preferably, the opening of the tape is larger than the size of the defect to be repaired, ensuring that the defect to be repaired is within the area of ​​the opening, and a small copper foil is pressed on the edge of the tape to connect the positive electrode when power is turned on, so that the positive and negative electrodes can be conductive.

[0018] Preferably, the catalyst comprises a pre-dip solution and an activated concentrated solution, and the catalyst forms a layer of colloidal palladium on the surface of the PCB substrate at a location to be repaired.

[0019] Preferably, the accelerator converts colloidal palladium into metallic palladium having electrical conductivity.

[0020] Preferably, the pen plating liquid is a copper sulfate liquid. After power is turned on, the copper sulfate liquid converts the solid copper, that is, the solid copper at the anode, into an ionic state, and then is plated onto the object at the cathode by means of electric current.

[0021] Preferably, the method uses a pen plating jig including a pulse power supply for increasing power supply and a jig for carrying a PCB substrate;

[0022] The fixture includes a fixture bottom and a fixture cover;

[0023] The bottom of the fixture is provided with a liquid medicine tank and a vibration motor for vibrating the liquid medicine tank to maintain its activity during the electroplating process;

[0024] The bottom cover of the jig is provided with a jig cover plate to prevent the liquid medicine from leaking out.

[0025] The present invention uses a certain proportion of liquid medicine to clean the defective points, adds liquid medicine to a special fixture for repair, and repairs the defective points by electroplating. Compared with manual repair methods of removing residual copper and welding, the present invention is simpler and has low requirements for operators, which is beneficial to reducing labor costs. Compared with manual repair, the present invention greatly reduces time costs, and increases the profits of circuit board manufacturing factories.

[0026] The potion used in the present invention includes sulfuric acid: used to clean the sulfuric acid on the surface of the object to achieve the purpose of purification. Pure water: to clean the excess and potion. Catalyst: to allow the repaired position to produce a layer of colloidal palladium, which fits the repaired position. Accelerator: to convert the colloidal palladium into metallic palladium to achieve the purpose of conductivity. Pen plating solution: can grow the copper ions in the potion in the designated place by increasing the appropriate current. Through the above potion, after electrolysis, the copper is plated to the required position, thereby repairing the PCB substrate. Compared with the manual electric welding method, the operation is more convenient, there is no technical requirement for the operator, and the operation is simpler and more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the fixture structure of the present invention.

[0028] Figure 2 It is a process flow chart of the present invention.

[0029] Figure 3 It is a schematic diagram of the structure of the product of the present invention before and after processing. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0031] This embodiment adopts a pen plating method, and the pen plating fixture used includes a pulse power supply for increasing the power supply and a fixture for carrying the PCB substrate;

[0032] The jig includes a jig bottom 1 and a jig cover 2;

[0033] The bottom 1 of the fixture is provided with a liquid medicine tank 3 and a vibration motor 4 which allows the liquid medicine in the liquid medicine tank 3 to vibrate and maintain activity during the electroplating process;

[0034] The bottom 1 of the jig is covered with a jig cover plate 2 to prevent the medicine from leaking out.

[0035] Specifically, the repair method of this embodiment is:

[0036] S1: Clean the defective area of ​​the PCB substrate with sulfuric acid (concentration 3%~5%) first, and then with pure water to remove the oxide layer and dirt in the defective area;

[0037] S2: Confirm the size of the points on the PCB substrate that need to be repaired, select the corresponding opening tape for pasting, paste two layers in total, and compact the tape to prevent gaps from leaking out and contaminating the board surface;

[0038] S3: Clean the opening of the tape with pure water, and then dry it with a dryer;

[0039] S4: Apply a catalyst to the defect at the opening of the tape. The catalyst can form a layer of colloidal palladium on the repair surface and adhere to the position to be repaired;

[0040] S5: Apply an accelerator to the opening of the tape and the defect, and dry it with a dryer. The accelerator converts colloidal palladium into metallic palladium, which is conductive.

[0041] S6: Use pure water to clean the opening of the tape and dry it with a dryer. It is worth noting that the catalyst will produce a layer of colloidal palladium on the repair surface. The colloidal palladium is sticky to objects and cannot be cleaned away by pure water.

[0042] S7: Remove the first layer of tape. The purpose of removing the first layer is that when applying the catalyst, some of the solution will stick to the first layer of tape. If electroplating is performed in this way, copper will be plated on the tape.

[0043] S8: Fit the part of the PCB substrate that needs to be repaired to the bottom of the pen plating jig, and drip pen plating liquid from the opening of the pen plating jig;

[0044] S9: Connect the positive pole of the pen plating jig to the copper foil, and the negative pole to the negative pole of the pen plating jig. Start the small motor to vibrate the pen plating liquid to ensure the activity of the pen plating liquid. Turn on the power for electroplating repair for 20 to 40 minutes.

[0045] S10: After the electroplating is completed, the excess solution is absorbed, the excess tape is torn off, and then an inspection is performed, the protruding part is polished, and the excess copper is burned off by laser. In this embodiment, the plating solution is a copper sulfate liquid containing a large amount of copper ions. The copper ions are gathered in a repair position by overcurrent.

[0046] The above is a detailed description of the present invention in combination with specific embodiments, and it cannot be determined that the specific implementation methods of the present invention are limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, making several equivalent substitutions or obvious modifications without departing from the concept of the present invention, and having the same performance or use, should be regarded as belonging to the patent protection scope of the present invention determined by the submitted claims.

Claims

1. A PCB substrate electroplating repair method, Features: The method steps are as follows: S1: Clean the defective area of ​​the PCB substrate with 3% to 5% sulfuric acid, and then clean it with pure water to remove the oxide layer and dirt in the defective area; S2: Confirm the size of the points on the PCB substrate that need to be repaired, select the corresponding opening tape for pasting, paste two layers in total, and compact the tape to prevent gaps from leaking out and contaminating the board surface; S3: Clean the opening of the tape with pure water, and then dry it with a dryer; S4: Apply catalyst to the opening of the tape and the defect; S5: Apply accelerator to the opening of the tape and the defect, and dry it with a dryer; S6: Clean the opening of the tape with pure water and dry it with a dryer; S7: remove the first layer of tape; S8: Fit the part of the PCB substrate that needs to be repaired to the bottom of the pen plating jig, and drip pen plating liquid from the opening of the pen plating jig; S9: Connect the positive electrode of the pen plating fixture to the copper foil, and the negative electrode to the negative electrode of the pen plating fixture. Start the small motor to vibrate the pen plating solution to ensure the activity of the pen plating solution. Power on the electroplating repair for 20 to 40 minutes. S10: After the electroplating is completed, the excess solution is absorbed, the excess tape is torn off, and then the inspection is carried out, the protruding parts are polished, and the excess copper is burned off by laser; The catalyst comprises a pre-soak solution and an activated concentrated solution, and the catalyst forms a layer of colloidal palladium on the surface of the PCB substrate where the repair is required; The accelerator converts the colloidal palladium into metallic palladium with conductivity; The pen plating solution is a copper sulfate liquid. After power is turned on, the copper sulfate liquid converts the solid copper, that is, the solid copper at the anode, into an ion state, and then plates it onto the object at the cathode by means of electric current. The method uses a pen plating jig including a pulse power supply for increasing power supply and a jig for carrying a PCB substrate; The fixture includes a fixture bottom and a fixture cover; The bottom of the fixture is provided with a liquid medicine tank and a vibration motor for vibrating the liquid medicine tank to maintain its activity during the electroplating process; The bottom cover of the jig is provided with a jig cover plate to prevent the medicine from leaking out.

2. A PCB substrate electroplating repair method according to claim 1, Features: The opening of the tape is larger than the size of the defect to be repaired, ensuring that the defect to be repaired is within the area of ​​the opening, and a small copper foil is pressed on the edge of the tape to connect the positive electrode when power is turned on, so that the positive and negative electrodes can be conductive.

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