Method for filling glue between thick copper wires of thin PCB (Printed Circuit Board)

Abstract

The invention relates to the technical field of glue filling between thick copper wires of a PCB, in particular to a method for filling glue between thick copper wires of a thin PCB. Comprising the following steps that cutting and positioning cutting are conducted, specifically, high-precision cutting equipment is used for conducting precise positioning cutting on CCL, and it is guaranteed that the sizes of plates are consistent; cleaning an inner layer and manufacturing a pattern: cleaning the plate surface through micro-etching liquid medicine, covering photosensitive ink, exposing, developing and etching to form a required pattern; and inner-layer AOI detection: comparing design patterns by using AOI equipment, ensuring the circuit design precision, and repairing defects. The manufacturing method is changed, the thin plate line spacing is brushed with resin and then directly covered with PP, then direct pressing is conducted, the resin for printing the line spacing and the PP are cured together through the pressing temperature, filling and leveling between thick copper wires are achieved, the plate baking and polishing and brushing processes after resin printing are reduced, and the problems that baking and polishing and brushing cost is low and manufacturing cannot be conducted are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of glue filling between thick copper wires of PCB, and specifically to a method for glue filling between thick copper wires of thin - board PCB. Background Art

[0002] In traditional PCB manufacturing processes, for thick - board thick copper (≥4OZ) wires, resin filling between wire spaces can be achieved by the resin filling wire - space method during lamination. However, this method is feasible for thick boards, but it is difficult to bake and brush the board for resin filling wire - space for thin boards with a thickness of less than 0.3mm; as a result, in the PCB industry, resin filling between wire spaces cannot be produced, failing to meet the demand.

[0003] Based on this, the present invention provides a method for glue filling between thick copper wires of thin - board PCB to solve the above - mentioned technical problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for glue filling between thick copper wires of thin - board PCB to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solutions:

[0006] A method for glue filling between thick copper wires of thin - board PCB is provided, including the following steps:

[0007] S1. Blanking and positioning cutting: Use high - precision cutting equipment to precisely position and cut the CCL to ensure consistent sheet sizes;

[0008] S2. Inner - layer cleaning and pattern making: Clean the board surface with micro - etching solution, cover with photosensitive ink and expose, develop, and etch to form the required pattern;

[0009] S3. Inner - layer AOI inspection: Use AOI equipment to compare with the designed pattern to ensure the accuracy of circuit design and repair defects;

[0010] S4. Inter - wire resin printing and PP covering: Precisely print resin and cover with PP material, and use white paper for isolation to achieve uniform distribution and curing of the resin;

[0011] S5. Lamination and curing: Brown - oxidize the inner - layer board, laminate according to normal lamination parameters to cure the resin and PP, and enhance the inter - layer bonding force;

[0012] S6. Drilling and positioning: Select drilling parameters according to requirements, and perform hole - position positioning after drilling;

[0013] S7. Copper deposition and electroplating: Use CuCL2 solution for copper deposition, and increase the thickness of the copper layer through electroplating process;

[0014] S8. Circuit manufacturing and solder mask treatment: After cleaning the board surface, press and laminate photosensitive dry film, then perform exposure, development, and etching to form circuit patterns, and finally carry out solder mask treatment;

[0015] S9. Character printing and surface treatment: Perform character printing and surface treatment according to requirements.

[0016] Preferably, the implementation steps of step S1 are as follows:

[0017] S1.1. Preparation of high-precision cutting equipment: Use a high-precision laser cutting machine with an accuracy of ±0.02 mm to prepare for cutting the incoming CCL material;

[0018] S1.2. Positioning of incoming CCL material: Adopt a mechanical positioning system to accurately position the incoming CCL material to ensure the cutting position is accurate;

[0019] S1.3. Setting of cutting parameters: Set the cutting speed to 2 m / s and the cutting depth to 90% of the CCL thickness, and start positioning cutting;

[0020] S1.4. Completion of cutting and inspection: After cutting, use a vernier caliper with an accuracy of ±0.05 mm to perform size inspection to ensure the consistency of the sheet size.

[0021] Preferably, the implementation steps of step S2 are as follows:

[0022] S2.1. Preparation of micro-etching solution: Prepare micro-etching solution according to the ratio of H2SO4:H2O2 = 3:1 to ensure the appropriate concentration of the solution;

[0023] S2.2. Cleaning of board surface: Immerse the board surface completely in the micro-etching solution, set the cleaning time to 2 minutes, and remove surface stains and oxides;

[0024] S2.3. Coating of photosensitive ink: Use an automatic coater to evenly apply photosensitive ink with a thickness of 8 μm to ensure full coverage;

[0025] S2.4. Drying and curing: Put the coated board surface into an oven at 80°C for 10 minutes for curing;

[0026] S2.5. Ultraviolet exposure: Use a high-precision exposure machine, set the exposure energy to 6 grids, and perform ultraviolet irradiation to cause the ink to undergo a polymerization reaction;

[0027] S2.6. Development, etching, and stripping: Perform development through the DES line, the concentration of the etching solution is 50 g / L, the etching time is 3 minutes, use NaOH solution with a concentration of 10% in the stripping section, and the treatment time is 1 minute.

[0028] Preferably, the implementation steps of step S3 are as follows:

[0029] S3.1. AOI Equipment Calibration: Calibrate the AOI equipment using a standard template to ensure an image comparison accuracy of ±3 μm;

[0030] S3.2. Image Comparison and Detection: Based on the designed pattern, use the AOI equipment to perform image comparison and detect the accuracy of the circuit design.

[0031] Preferably, the implementation steps of step S4 are as follows:

[0032] S4.1. Resin Printing Equipment Preparation: Use a resin printer with an accuracy of ±2 μm to prepare for resin printing;

[0033] S4.2. Resin Coating: Set the resin printing thickness to 15 μm and the printing speed to 0.5 m / s, and evenly coat the resin on the entire board surface;

[0034] S4.3. PP Material Preparation and Covering: Use PP material preheated at 120 °C and directly cover it on the resin surface to ensure no bubbles;

[0035] S4.4. White Paper Isolation: Cover a layer of 0.1 mm thick white paper on the PP material as an isolation layer to prevent resin adhesion.

[0036] Preferably, the implementation steps of step S5 are as follows:

[0037] S5.1. Inner Layer Board Brown Oxidation Treatment: Perform brown oxidation treatment on all layers of the inner layer boards. The concentration of the brown oxidation solution is 30 g / L, the treatment temperature is 60 °C, and the time is 10 minutes;

[0038] S5.2. Laminating Parameter Setting: Set the laminating machine temperature to 180 °C, the pressure to 5 MPa, and the laminating time to 90 minutes;

[0039] S5.3. Laminating and Curing: Perform laminating and punching according to the set laminating parameters to cure the resin and PP together with the printed line pitch.

[0040] Preferably, the implementation steps of step S6 are as follows:

[0041] S6.1. Drilling Equipment Preparation: Use a high-precision drilling machine with an accuracy of ±0.01 mm to prepare for drilling;

[0042] S6.2. Drilling Parameter Setting: According to the drilling requirements and the type of board, set the drill bit diameter to 0.3 mm, the rotation speed to 25000 rpm, and the feed speed to 20 mm / min;

[0043] S6.3. Drilling and Positioning: Perform drilling operations, and then use high-precision positioning equipment to accurately position the hole positions.

[0044] Preferably, the implementation steps of step S7 are as follows:

[0045] S7.1. Preparation of copper deposition solution: Prepare the copper deposition solution according to the ratio of CuCL2:H2O = 1:10 to ensure moderate solution concentration;

[0046] S7.2. Copper deposition on the whole board and in holes: Immerse the whole board and holes completely in the copper deposition solution, set the deposition time to 30 minutes, and form a uniform copper layer;

[0047] S7.3. Setting of electroplating parameters: Set the electroplating solution concentration as CuSO4:H2SO4 = 1:4, the current density as 2 ASD, and the electroplating time as 60 minutes;

[0048] S7.4. Electroplating and additional plating: Through the electroplating process, convert copper - phosphorus balls into copper ions and deposit them on the board surface to increase the thickness of the copper layer.

[0049] Preferably, the implementation steps of step S8 are as follows:

[0050] S8.1. Re - cleaning of the board surface: Use micro - etching solution and brush process to re - clean the board surface to ensure no stains and oxides on the surface;

[0051] S8.2. Laminating of photosensitive dry film: Uniformly laminate a photosensitive dry film with a thickness of 10 μm to ensure full coverage;

[0052] S8.3. Exposure, development and etching: Use an exposure machine for ultraviolet irradiation with an exposure energy of 7 grids, and then perform development and etching operations to obtain the required circuit pattern;

[0053] S8.4. Preparation of solder mask ink: Prepare the solder mask ink according to the ratio of photosensitive ink:diluent = 3:1 to ensure moderate ink viscosity;

[0054] S8.5. Solder mask treatment: Print a layer of solder mask ink on the board surface, perform pre - baking, and use an exposure machine for ultraviolet irradiation to form a solder mask layer.

[0055] Preferably, the implementation steps of step S9 are as follows:

[0056] S9.1. Preparation of character printer: Use a character printer with a precision of ±0.1 mm to prepare for character printing;

[0057] S9.2. Setting of character printing parameters: Set the printed character size as 2 mm, the printing speed as 0.3 m / s, and start character printing;

[0058] S9.3. Printing of product model and date: Print key information such as product model and production date according to requirements;

[0059] S9.4. Surface treatment selection: Select immersion gold, immersion tin, OSP or hot air solder leveling process according to requirements;

[0060] S9.5. Surface treatment operation: Perform surface treatment operation, the concentration of immersion gold solution is 1 g / L, and the treatment time is 30 minutes.

[0061] Compared with the prior art, the beneficial effects of the present invention are:

[0062] By changing the manufacturing method, the present invention directly covers the thin plate line pitch with PP after brushing resin, and then directly presses it. The resin and PP of the printed line pitch are cured together by the pressing temperature, which not only fills the gap between thick copper wires, but also reduces the baking and brushing processes after resin printing, solves the problems of baking and brushing costs, and the situation where it cannot be manufactured. Detailed implementation manners

[0063] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

[0064] Embodiment

[0065] The present invention provides a method for filling glue between thick copper wires of a thin plate PCB. In practical applications, specifically, it includes the following steps:

[0066] S1. Blanking and positioning cutting: Use high-precision cutting equipment to accurately position and cut the CCL to ensure that the plate size is consistent;

[0067] In this embodiment, it should also be noted that the implementation steps of step S1 are as follows:

[0068] S1.1. Preparation of high-precision cutting equipment: Use a high-precision laser cutting machine with an accuracy of ±0.02 mm to prepare for cutting the incoming CCL;

[0069] S1.2. Positioning of incoming CCL: Use a mechanical positioning system to accurately position the incoming CCL to ensure that the cutting position is accurate;

[0070] S1.3. Setting of cutting parameters: Set the cutting speed to 2 m / s and the cutting depth to 90% of the CCL thickness, and start positioning cutting;

[0071] S1.4. Completion and inspection of cutting: After cutting, use a vernier caliper with an accuracy of ±0.05 mm to perform size inspection to ensure that the plate sizes are the same;

[0072] S2. Inner layer cleaning and pattern making: Clean the board surface with micro-etching solution, cover with photosensitive ink, and then expose, develop, and etch to form the required pattern;

[0073] In this embodiment, it should also be noted that the implementation steps of step S2 are as follows:

[0074] S2.1. Preparation of micro-etching solution: Prepare micro-etching solution according to the ratio of H2SO4:H2O2 = 3:1 to ensure appropriate solution concentration;

[0075] S2.2. Board surface cleaning: Immerse the board surface completely in the micro-etching solution, set the cleaning time to 2 minutes to remove surface stains and oxides;

[0076] S2.3. Coverage of photosensitive ink: Use an automatic coater to evenly apply photosensitive ink with a thickness of 8μm to ensure full coverage;

[0077] S2.4. Drying and curing: Place the coated board surface in an oven at 80°C for a curing time of 10 minutes;

[0078] S2.5. Ultraviolet exposure: Use a high-precision exposure machine, set the exposure energy to 6 grids, and perform ultraviolet irradiation to cause the ink to undergo a polymerization reaction;

[0079] S2.6. Development, etching, and film removal: Perform development through the DES line, the etching solution concentration is 50g / L, the etching time is 3 minutes, and use NaOH solution with a concentration of 10% in the film removal section for a treatment time of 1 minute;

[0080] S3. Inner layer AOI inspection: Use AOI equipment to compare with the designed pattern to ensure the accuracy of the circuit design and repair defects;

[0081] In this embodiment, it should also be noted that the implementation steps of step S3 are as follows:

[0082] S3.1. Calibration of AOI equipment: Calibrate the AOI equipment using a standard template to ensure the image comparison accuracy is ±3μm;

[0083] S3.2. Image comparison and inspection: Based on the designed pattern, use AOI equipment for image comparison to detect the accuracy of the circuit design;

[0084] S4. Inter-line resin printing and PP coverage: Precision print resin and cover with PP material, use white paper for isolation to achieve uniform distribution and curing of the resin;

[0085] In this embodiment, it should also be noted that the implementation steps of step S4 are as follows:

[0086] S4.1. Preparation of resin printing equipment: Use a resin printer with an accuracy of ±2μm to prepare for resin printing;

[0087] S4.2. Resin Coating: Set the resin printing thickness to 15 μm and the printing speed to 0.5 m / s, and evenly coat the entire board with resin on the board surface;

[0088] S4.3. PP Material Preparation and Covering: Use preheated PP material at 120 °C and directly cover it on the resin surface to ensure no air bubbles;

[0089] S4.4 White Paper Isolation: Cover a layer of 0.1 mm thick white paper on the PP material as an isolation layer to prevent resin adhesion;

[0090] S5. Laminating and Curing: Brown the inner layer board and laminate it according to normal lamination parameters to cure the resin and PP and enhance the interlayer bonding force;

[0091] In this embodiment, it should also be noted that the implementation steps of step S5 are as follows:

[0092] S5.1. Inner Layer Board Browning Treatment: Brown all layers of the inner layer board. The concentration of the browning solution is 30 g / L, the treatment temperature is 60 °C, and the time is 10 minutes;

[0093] S5.2. Lamination Parameter Setting: Set the lamination machine temperature to 180 °C, the pressure to 5 MPa, and the lamination time to 90 minutes;

[0094] S5.3. Laminating and Curing: Perform lamination and punching according to the set lamination parameters to cure the resin and PP of the printed line pitch together;

[0095] S6. Drilling and Positioning: Select drilling parameters according to requirements and perform hole position positioning after drilling;

[0096] In this embodiment, it should also be noted that the implementation steps of step S6 are as follows:

[0097] S6.1. Drilling Equipment Preparation: Use a high-precision drilling machine with an accuracy of ±0.01 mm to prepare for drilling;

[0098] S6.2. Drilling Parameter Setting: According to the drilling requirements and the type of board, set the drill bit diameter to 0.3 mm, the rotation speed to 25000 rpm, and the feed speed to 20 mm / min;

[0099] S6.3. Drilling and Positioning: Perform drilling operations, and then use high-precision positioning equipment to accurately position the hole positions;

[0100] S7. Copper Plating and Electroplating: Use CuCL2 solution for copper plating and increase the copper layer thickness through electroplating process;

[0101] In this embodiment, it should also be noted that the implementation steps of step S7 are as follows:

[0102] S7.1. Immersion Copper Solution Preparation: Prepare the immersion copper solution according to the ratio of CuCL2:H2O = 1:10 to ensure moderate solution concentration;

[0103] S7.2. Immersion Copper on the Whole Board and in the Holes: Immerse the whole board and the holes completely in the immersion copper solution, set the deposition time to 30 minutes to form a uniform copper layer;

[0104] S7.3. Electroplating Parameter Setting: Set the electroplating solution concentration as CuSO4:H2SO4 = 1:4, the current density as 2 ASD, and the electroplating time as 60 minutes;

[0105] S7.4. Electroplating and Additional Plating: Through the electroplating process, convert the copper - phosphorus balls into copper ions and deposit them on the board surface to increase the thickness of the copper layer;

[0106] S8. Circuit Production and Solder Mask Treatment: After cleaning the board surface, press and cover the photosensitive dry film, then perform exposure, development, and etching to form the circuit pattern, and then carry out the solder mask treatment;

[0107] In this embodiment, it should also be noted that the implementation steps of step S8 are as follows:

[0108] S8.1. Re - cleaning the Board Surface: Use micro - etching solution and brush process to re - clean the board surface to ensure no stains and oxides on the surface;

[0109] S8.2. Pressing and Covering the Photosensitive Dry Film: Uniformly press and cover a photosensitive dry film with a thickness of 10 μm to ensure full coverage;

[0110] S8.3. Exposure, Development, and Etching: Use an exposure machine for ultraviolet irradiation with an exposure energy of 7 grids, and then perform development and etching operations to obtain the required circuit pattern;

[0111] S8.4. Solder Mask Ink Preparation: Prepare the solder mask ink according to the ratio of photosensitive ink:diluent = 3:1 to ensure moderate ink viscosity;

[0112] S8.5. Solder Mask Treatment: Print a layer of solder mask ink on the board surface, perform pre - baking, and use an exposure machine for ultraviolet irradiation to form the solder mask layer;

[0113] S9. Character Spraying and Surface Treatment: Perform character spraying and surface treatment according to requirements;

[0114] In this embodiment, it should also be noted that the implementation steps of step S9 are as follows:

[0115] S9.1. Preparation of the Character Spraying Machine: Use a character spraying machine with an accuracy of ±0.1 mm to prepare for character spraying;

[0116] S9.2. Text jet printing parameter setting: Set the jet printing font size to 2 mm, the jet printing speed to 0.3 m / s, and start text jet printing;

[0117] S9.3. Product model and date jet printing: Jet print the key information of product model and production date according to requirements;

[0118] S9.4. Surface treatment selection: Select immersion gold, immersion tin, OSP or hot air solder leveling process treatment according to requirements;

[0119] S9.5. Surface treatment operation: Conduct surface treatment operation, with the concentration of immersion gold solution being 1 g / L and the treatment time being 30 minutes.

[0120] Perform glue filling through the above steps, and send the samples for inspection and conduct conduction and insulation tests. The steps are as follows:

[0121] Conduction test: Use a high-precision multimeter and an insulation tester to conduct the conduction test in a test environment of room temperature 25 ± 5°C and relative humidity 50 ± 10%. Select several pairs of copper wire endpoints on the prepared PCB board, use the multimeter to measure the resistance between each pair of endpoints, and record the data;

[0122] Among them, the judgment criterion is: a resistance value less than 0.1 Ω is regarded as good conduction;

[0123] Insulation test: Select the distance between adjacent copper wire pairs or between the copper wire and the board edge, use the insulation tester to measure the insulation resistance between these distances, and record the data;

[0124] Among them, the judgment criterion is: an insulation resistance greater than 10 MΩ is regarded as qualified insulation;

[0125] The experimental data is shown in Table 1:

[0126] Table 1 Data table of conduction test and insulation test

[0127] Test Items Test Points / Pairs Test Results Judgment Conductivity Test 1-2 0.05Ω Good 3-4 0.03Ω Good n-m 0.07Ω Good Insulation Test A-B 20MΩ Qualified C-D 15MΩ Qualified X-Y 12MΩ Qualified

[0128] According to the above test data, the resistance values of the conduction test are all less than 0.1 Ω, the conduction between copper wires is good, and the insulation resistances of the insulation test are all greater than 10 MΩ, and the insulation performance is qualified;

[0129] Therefore, the conductivity and insulation of the preparation method of the present invention both meet the quality requirements;

[0130] Perform glue filling through the above steps, and conduct 100% AVI scanning comparison on the samples:

[0131] Use an AVI (Automatic Visual Inspection) system for 100% scanning. Set the scanning parameters according to the designed pattern, including scanning speed and resolution. Compare the scanning results with the standard designed pattern, record the points or areas that do not meet the requirements, and repair or scrap the products that do not meet the requirements;

[0132] The method for calculating the yield rate is to count the ratio of the number of finished products to the total number of products prepared to obtain the yield rate;

[0133] The yield rate data is shown in Table 2:

[0134] Table 2 Yield Rate Data Test Data

[0135] Manufacturing Batch Total Quantity Unqualified Quantity Finished Product Quantity Finished Product Rate The First Batch 1000 10 990 99％ The Second Batch 1500 15 1485 99％ The Third Batch 2000 20 1980 99％ The Nth Batch 5000 50 4950 99％

[0136] The yield rate of each batch filled with glue by the method of the present invention remains at about 99%. Therefore, the preparation method of the present invention has high feasibility, relatively few unqualified quantities, and can ensure product quality through repair or scrap treatment. Therefore, the preparation method of the present invention has high feasibility and reliability in practical applications.

[0137] In summary, the present invention changes the manufacturing method. After using brush resin for the thin plate line pitch, directly cover it with PP, and then directly press it. Utilize the pressing temperature to cure the resin and PP of the printed line pitch together, which can fill the space between thick copper wires, reduce the baking and grinding processes after resin printing, solve the problems of baking and grinding costs, and the situation of being unable to manufacture.

[0138] In the description of this specification, the description referring to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0139] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the relevant technical fields can understand and utilize the present invention well. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A method for filling glue between thick copper wires of a thin - plate PCB, characterized in that, It includes the following steps: S1. Blanking and positioning cutting: Use high-precision cutting equipment to precisely position and cut the CCL to ensure consistent sheet sizes; S2. Inner layer cleaning and pattern making: Clean the board surface with micro-etching solution, cover with photosensitive ink and expose, develop, and etch to form the required pattern; S3. Inner layer AOI inspection: Use AOI equipment to compare with the designed pattern to ensure the accuracy of circuit design and repair defects; S4. Inter-line resin printing and PP covering: Precisely print resin and cover with PP material, isolate with white paper to achieve uniform distribution and curing of the resin; S5. Laminating and curing: Brown the inner layer board, laminate according to normal lamination parameters to cure the resin and PP, and enhance the inter-layer bonding force; S6. Drilling and positioning: Select drilling parameters according to requirements, and perform hole positioning after drilling; S7. Copper deposition and electroplating: Use CuCL2 solution for copper deposition, and increase the thickness of the copper layer through electroplating process; S8. Circuit making and solder mask treatment: Clean the board surface and then press and cover with photosensitive dry film, expose, develop, and etch to form the circuit pattern, and then perform solder mask treatment; S9. Character printing and surface treatment: Perform character printing and surface treatment according to requirements.

2. The method for filling glue between thick copper wires of a thin - plate PCB according to claim 1, characterized in that, The implementation steps of step S1 are as follows: S1.

1. Preparation of high-precision cutting equipment: Use a high-precision laser cutting machine with an accuracy of ±0.02 mm to prepare for cutting the incoming CCL; S1.

2. Positioning of incoming CCL: Use a mechanical positioning system to accurately position the incoming CCL to ensure accurate cutting positions; S1.

3. Setting of cutting parameters: Set the cutting speed to 2 m / s and the cutting depth to 90% of the CCL thickness, and start positioning cutting; S1.

4. Completion and inspection of cutting: After cutting, use a vernier caliper with an accuracy of ±0.05 mm for size inspection to ensure consistent sheet sizes.

3. A method for filling glue between thick copper wires of a thin - plate PCB according to claim 2, characterized in that, The implementation steps of step S2 are as follows: S2.

1. Preparation of micro-etching solution: Prepare micro-etching solution according to the ratio of H2SO4:H2O2 = 3:1 to ensure appropriate solution concentration; S2.

2. Cleaning of board surface: Immerse the board surface completely in the micro-etching solution, set the cleaning time to 2 minutes to remove surface stains and oxides; S2.

3. Covering with photosensitive ink: Use an automatic coater to evenly apply photosensitive ink with a thickness of 8 μm to ensure full coverage; S2.

4. Drying and curing: Put the coated board surface into an oven at 80°C for 10 minutes for curing; S2.

5. Ultraviolet exposure: Use a high-precision exposure machine, set the exposure energy to 6 grids, and perform ultraviolet irradiation to cause the ink to polymerize; S2.

6. Development, etching, and stripping: Perform development through the DES line, the etching solution concentration is 50 g / L, the etching time is 3 minutes, and use NaOH solution with a concentration of 10% in the stripping section for 1 minute of treatment.

4. A method for filling glue between thick copper wires of a thin plate PCB according to claim 3, characterized in that, The implementation steps of step S3 are as follows: S3.

1. Calibration of AOI equipment: Calibrate the AOI equipment with a standard sample to ensure the image comparison accuracy is ±3 μm; S3.

2. Image comparison and inspection: Compare the images using the AOI equipment according to the designed pattern to detect the accuracy of circuit design.

5. A method for filling glue between thick copper wires of a thin plate PCB according to claim 4, characterized in that, The implementation steps of step S4 are as follows: S4.

1. Preparation of the resin printing equipment: Use a resin printer with an accuracy of ±2 μm and prepare for resin printing; S4.

2. Resin coating: Set the resin printing thickness to 15 μm and the printing speed to 0.5 m / s, and evenly coat the resin on the entire board surface; S4.

3. Preparation and covering of PP material: Use PP material preheated at 120 °C and directly cover it on the resin surface to ensure no bubbles; S4.

4. White paper isolation: Cover a layer of 0.1 mm thick white paper on the PP material as an isolation layer to prevent resin adhesion.

6. A method for filling glue between thick copper wires of a thin plate PCB according to claim 5, characterized in that, The implementation steps of step S5 are as follows: S5.

1. Inner layer board brownification treatment: Brownify all layers of the inner layer board. The concentration of the brownification solution is 30 g / L, the treatment temperature is 60 °C, and the time is 10 minutes; S5.

2. Lamination parameter setting: Set the lamination machine temperature to 180 °C, the pressure to 5 MPa, and the lamination time to 90 minutes; S5.

3. Lamination and curing: Perform lamination and drilling according to the set lamination parameters to cure the resin and PP with the printed line pitch together.

7. A method for filling glue between thick copper wires of a thin - plate PCB according to claim 6, characterized in that, The implementation steps of step S6 are as follows: S6.

1. Drilling equipment preparation: Use a high-precision drilling machine with an accuracy of ±0.01 mm and prepare for drilling; S6.

2. Drilling parameter setting: According to the drilling requirements and the type of board, set the drill bit diameter to 0.3 mm, the rotation speed to 25000 rpm, and the feed speed to 20 mm / min; S6.

3. Drilling and positioning: Perform drilling operations, and then use high-precision positioning equipment to accurately position the hole positions.

8. A method for filling glue between thick copper wires of a thin - plate PCB according to claim 7, characterized in that, The implementation steps of step S7 are as follows: S7.

1. Preparation of the copper deposition solution: Prepare the copper deposition solution according to the ratio of CuCL2:H2O = 1:10 to ensure that the solution concentration is appropriate; S7.

2. Copper deposition on the entire board and in the holes: Immerse the entire board and the holes completely in the copper deposition solution, set the deposition time to 30 minutes, and form a uniform copper layer; S7.

3. Electroplating parameter setting: Set the electroplating solution concentration to CuSO4:H2SO4 = 1:4, the current density to 2 ASD, and the electroplating time to 60 minutes; S7.4 Electroplating additional plating: Through the electroplating process, convert the copper-phosphorus balls into copper ions and deposit them on the board surface to increase the thickness of the copper layer.

9. A method for filling glue between thick copper wires of a thin - plate PCB according to claim 8, characterized in that, The implementation steps of step S8 are as follows: S8.

1. Re-cleaning of the board surface: Use micro-etching solution and brush process to re-clean the board surface to ensure that there are no stains and oxides on the surface; S8.

2. Laminating photosensitive dry film: Uniformly laminate a layer of photosensitive dry film with a thickness of 10 μm to ensure full coverage; S8.

3. Exposure, development and etching: Use an exposure machine for ultraviolet irradiation, the exposure energy is 7 grids, and then perform development and etching operations to obtain the required circuit pattern; S8.

4. Preparation of solder mask ink: Prepare solder mask ink according to the ratio of photosensitive ink:diluent = 3:1 to ensure that the ink viscosity is appropriate; S8.

5. Solder mask treatment: Print a layer of solder mask ink on the board surface and perform pre-baking, and use an exposure machine for ultraviolet irradiation to form a solder mask layer.

10. A method for filling glue between thick copper wires of a thin - plate PCB according to claim 9, characterized in that, The implementation steps of step S9 are as follows: S9.

1. Preparation of the character printer: Use a character printer with an accuracy of ±0.1 mm and prepare for character printing; S9.

2. Character Jet Printing Parameter Setting: Set the jet printing font size to 2 mm, the jet printing speed to 0.3 m / s, and start character jet printing; S9.

3. Product Model and Date Jet Printing: Jet print the key information of product model and production date according to requirements; S9.

4. Surface Treatment Selection: Select the surface treatment process of immersion gold, immersion tin, OSP or spray tin according to requirements; S9.

5. Surface Treatment Operation: Conduct surface treatment operation, with the concentration of immersion gold solution being 1 g / L and the treatment time being 30 minutes.