Manufacturing method of high-order large-size pen electric printed board

Abstract

The invention discloses a manufacturing method of a high-order large-size pen-type printed board. The manufacturing method comprises the following steps: making a yin-yang copper-clad copper core board according to the size of a jointed board; respectively manufacturing inner-layer circuits on the two surfaces of the cathode and anode copper-clad copper core plate by adopting a vacuum two-fluid etching machine and a single-side exposure and single-side etching mode; sequentially overlapping the yin-yang copper-clad copper core plate and the outer-layer copper foil according to requirements through prepregs to form an inner-layer plate; a blind hole and a via hole are sequentially drilled in the inner layer plate, and copper deposition and hole filling electroplating of the whole plate are sequentially carried out on the inner layer plate; resin hole plugging and curing are carried out on the via holes, redundant resin on the hole openings and the board surface is ground off, and then longitudinal and latitudinal secondary board grinding is carried out on the inner layer board; manufacturing an outer-layer circuit on the inner-layer board by adopting a vacuum two-fluid etching machine and a negative film process; and performing post-process treatment on the inner layer board to obtain the printed board. The method provided by the invention solves the problem that the cathode and anode copper thick copper-clad core plate is difficult to manufacture, and ensures that the impedance control meets the design requirements.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board manufacturing technology, specifically to a method for manufacturing a high-end, large-size laptop printed circuit board. Background Technology

[0002] The rise of esports has brought a surge of attention to the laptop market. High-end gaming laptops are demanding higher efficiency, higher definition, and smoother performance, making their market prospects and future prospects extremely promising. The popularity of esports has brought new performance and quality requirements to high-end gaming laptops, and has also created new market opportunities for PCB manufacturers.

[0003] High-end laptop motherboards require high-speed, high-definition, and efficient transmission performance. Many chips and components need to be densely arranged on the motherboard to make room for the battery and other connected devices. Therefore, the PCB needs to adopt a high-density and highly integrated structural design.

[0004] The standard design process for medium to large-sized laptop printed circuit boards is as follows:

[0005] Material cutting → Inner layer patterning → Inner layer etching → Inner layer AOI → Browning → Lamination → Drilling target holes → LDD browning → Laser drilling → Mechanical drilling → Browning removal → Electroless copper plating → Full board hole filling → Resin plugging → Ceramic grinding plate 1 → Resin plugging AOI → Outer layer patterning → Outer layer etching → Outer AOI → Silk screen solder mask / characters → Impedance testing → Pre-forming testing → Secondary drilling → Forming → FQC1 → OSP → FQC2 → FQA → Packaging.

[0006] Printed circuit boards (PCBs) are trending towards smaller size, higher precision, and greater intelligence. More and more customers have extremely stringent impedance requirements for PCBs, especially for inner layers. Recently, customers have encountered situations where the copper thickness on the front and back of the inner layer core board is inconsistent (also known as uneven copper thickness), leading to significant risks and manufacturing difficulties during production. Therefore, eliminating poor inner layer impedance during mass production and addressing the issue of inconsistent copper thickness on the front and back sides is a major challenge in the PCB industry. Conventional manufacturing processes cannot meet the needs of such products, line parameters cannot be matched and adjusted, and existing etching methods are inadequate for processing these products. Furthermore, regardless of whether it's inner or outer layer circuitry, when line width and spacing are required to be 0.05 / 0.05mm and impedance is required to be ±8%, the circuit pattern is extremely fine. Using conventional electroplating and etching methods would result in excessively thick copper and poor etching uniformity, failing to meet customer impedance control requirements. Summary of the Invention

[0007] In view of the above-mentioned technical defects, the present invention provides a method for manufacturing high-end large-size printed circuit boards for laptops, which solves the problem of difficult manufacturing of thick copper-clad laminates with positive and negative copper cores, and ensures that impedance control meets design requirements.

[0008] To address the aforementioned technical problems, this invention provides a method for manufacturing a high-end, large-size laptop printed circuit board, comprising the following steps:

[0009] S1. Cut out the male and female copper-clad core boards according to the panel size, wherein the copper layer thickness of the first surface of the male and female copper-clad core boards is greater than the copper layer thickness of the second surface.

[0010] S2. A film is applied to the copper-clad laminate, and then the inner layer circuit pattern is formed on the first surface by exposure and development in sequence. The film on the second surface is fully exposed. Then, the copper-clad laminate is etched by a vacuum two-fluid etching machine, and then the film is removed to obtain the inner layer circuit on the first surface.

[0011] S3. A film is applied to the copper-clad laminate, and then the inner layer circuit pattern is formed on the second surface by exposure and development. The film on the first surface is fully exposed. Then, the copper-clad laminate is etched by a vacuum two-fluid etching machine, and then the film is removed to obtain the inner layer circuit on the second surface.

[0012] S4. The inner layer board is formed by sequentially stacking the above-mentioned copper-clad core board and outer copper foil using a prepreg.

[0013] S5. Drill blind holes and through holes in sequence on the inner layer board, and perform copper plating and full-board hole filling electroplating on the inner layer board in sequence to fill the blind holes and plate copper layer on the hole wall of the through holes.

[0014] S6. Resin is plugged and cured on the through holes, and then the excess resin on the hole opening and board surface is ground off by a grinding plate. Then the inner layer board is ground twice in the warp and weft directions.

[0015] S7. A film is attached to the inner layer board, and then the outer layer circuit pattern is formed on the inner layer board by exposure and development in sequence. The outer layer circuit is obtained by etching the inner layer board with a vacuum two-fluid etching machine.

[0016] S8. The inner layer board is sequentially processed with solder mask, surface treatment and cutting to obtain the printed circuit board.

[0017] Furthermore, in step S1, the copper layer thickness on the first surface of the copper-clad laminate is 2 oz, and the copper layer thickness on the second surface is 0.5 oz.

[0018] Furthermore, in step S2, the etching factor during etching is ≥3.

[0019] Furthermore, step S1 also includes cutting out two copper-clad core boards with a copper thickness of 0.5oz each according to the panel size, and then sequentially fabricating the inner layer circuitry on the copper-clad core boards through film application, exposure, and development.

[0020] Furthermore, in step S4, two male and female copper clad laminates, two copper clad laminates and an outer copper foil are stacked sequentially as required by a prepreg to form an inner layer board; wherein, the stacking order from top to bottom is outer copper foil, prepreg, male and female copper clad laminates, prepreg, copper clad laminate, prepreg, copper clad laminate, prepreg, copper clad laminate, prepreg, male and female copper clad laminates, prepreg and outer copper foil, and the second surface of the upper and lower male and female copper clad laminates is adjacent to the inner copper clad laminate.

[0021] Furthermore, the steps between S7 and S8 include the following:

[0022] S71. The inner layer plate and the outer copper foil are stacked sequentially as required using a prepreg to form the outer layer plate.

[0023] S72. Drill blind holes and through holes in sequence on the outer layer board, and perform copper plating and full-board hole filling electroplating on the outer layer board in sequence to fill the blind holes and plate copper layer on the hole walls of the through holes.

[0024] S73. Resin is plugged and cured in the through holes, and then the excess resin on the hole openings and board surface is ground off by a grinding plate. Then, the outer layer board is ground twice in the warp and weft directions.

[0025] S74. A film is applied to the outer layer board, and then the outer layer circuit pattern is formed on the outer layer board by exposure and development in sequence. The outer layer circuit is obtained by etching the outer layer board using a vacuum two-fluid etching machine, and a second-order printed circuit board is produced.

[0026] Furthermore, the steps between S74 and S8 include the following:

[0027] S75. Repeat steps S71 to S74 at least once to finally obtain a three-level or higher printed circuit board.

[0028] Furthermore, mechanical drilling is used for drilling through holes, while laser drilling is used for drilling blind holes. Before each laser drilling, the board is first subjected to LDD browning treatment. After LDD browning, the thickness of the surface copper layer is controlled at 7-9μm. After each through hole is drilled, the board is subjected to debrowning treatment.

[0029] Furthermore, during the full-board through-hole electroplating, the copper layer thickness of the through-hole wall is plated to ≥20μm, and the copper thickness of the board surface layer is controlled at 35±5μm.

[0030] Furthermore, after each secondary grinding in the warp and weft directions, the board is subjected to micro-etching to reduce the copper thickness on the board surface to 22±3μm.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] This invention targets copper-clad laminates with male and female surfaces. Instead of conventional inner-layer exposure etching, single-sided exposure etching is used on both surfaces. A vacuum two-fluid etching machine is used to etch both surfaces separately, ensuring uniform linewidth after etching. This ensures impedance control within the process range, meeting the requirements for 50 / 50µm linewidth and spacing on the copper-clad laminate. A second grinding process is performed in the warp and weft directions after the first grinding to ensure the physical tensile coefficient in the warp and weft directions is within a controllable range and to ensure uniform copper thickness on the surface, thus meeting the requirements for copper thickness uniformity and ±0.05mm expansion / contraction of the finished product.

[0033] Secondly, after each secondary grinding in the warp and weft directions, the board is micro-etched to reduce copper content, which facilitates the subsequent etching of fine lines and avoids excessive copper thickness that could lead to severe side etching and line etching failure. In the process of fabricating the outer layer lines, a vacuum two-fluid etching machine is also used to ensure etching uniformity of ≥95% and meet the requirements of 50 / 50um line width and spacing for the outer layer lines. Detailed Implementation

[0034] To better understand the technical content of this invention, the technical solution of this invention will be further introduced and explained below in conjunction with specific embodiments.

[0035] Example

[0036] The method for manufacturing a high-end, large-size laptop printed circuit board shown in this embodiment includes the following processing steps in sequence:

[0037] (1) Cutting: Cut the male and female copper clad core boards and copper core boards according to the panel size of 520mm×620mm. The thickness of the copper core board is 0.5mm, and the copper layer thickness on both surfaces of the copper core board is 0.5oz. The thickness of the male and female copper clad core boards is 0.5mm, and the copper layer thickness on the first surface of the male and female copper clad core boards is 2oz, and the copper layer thickness on the second surface is 0.5oz.

[0038] (2) Inner layer circuit fabrication (negative film process): including the fabrication of copper-clad core boards and copper-clad core boards with positive and negative copper.

[0039] In this process, a photosensitive film is coated onto the copper-clad laminate using a vertical coating machine. The film thickness is controlled at 8μm. A fully automatic exposure machine is used, employing 5-6 exposure scales (or 21 exposure scales) to expose the inner layer circuitry. After development, the inner layer circuitry pattern is formed. Inner layer etching involves etching the inner layer circuitry onto the exposed and developed copper-clad laminate. The inner layer linewidth is measured to be 3mil. Inner layer AOI is then performed, followed by inspection for defects such as open circuits, short circuits, gaps, and pinholes in the inner layer circuitry. Defective products are scrapped, while defect-free products proceed to the next process.

[0040] The copper-clad laminate (CCL) is coated with a photosensitive film using a vertical coating machine, with the film thickness controlled at 8μm. A fully automatic exposure machine is used, employing 5-6 exposure increments (or 21 exposure increments) to expose the inner layer circuitry on the first surface, while the second surface is fully exposed. After development, the inner layer circuitry pattern is formed. The inner layer is then etched, followed by etching using a vacuum two-fluid etching machine. The film is then stripped to obtain the inner layer circuitry on the first surface, with a measured linewidth of 3mil. Finally, the photosensitive film is coated again using a vertical coating machine, with the film thickness controlled at 8μm. The process involves using a fully automatic exposure machine with 5-6 exposure scales (or 21 exposure scales) to expose the inner layer circuitry on the second surface, while the first surface is fully exposed. After development, the inner layer circuitry pattern is formed. The inner layer is then etched, and a vacuum two-fluid etching machine is used to etch the copper-clad laminate. The film is then removed to obtain the inner layer circuitry on the second surface. The inner layer linewidth is measured to be 3 mil. The inner layer undergoes AOI (Automated Optical Inspection), and then defects such as open circuits, short circuits, gaps, and pinholes in the inner layer circuitry are inspected. Defective products are scrapped, while defect-free products proceed to the next process.

[0041] In the above, the etching factor of the first surface is ≥3 when using a vacuum two-fluid etching machine to ensure line width uniformity, thereby ensuring that the impedance is controlled within the process range.

[0042] (3) Browning: The copper-clad laminate and copper core board are browned to enhance the bonding force between the copper-clad laminate and copper core board and the prepreg.

[0043] (4) Lamination: The inner layer board is formed by stacking two male and female copper clad laminates, two copper clad laminates and outer copper foil in sequence according to the requirements through a prepreg. The stacking sequence from top to bottom is outer copper foil, prepreg, male and female copper clad laminate, prepreg, copper clad laminate, prepreg, copper clad laminate, prepreg, copper clad laminate, prepreg, and outer copper foil. The second surface of the upper and lower male and female copper clad laminates is adjacent to the inner copper clad laminate, so that the entire stacked structure is symmetrical and the pressing force is evenly distributed during lamination, avoiding problems such as uneven pressing force and board bursting caused by asymmetrical stacked structure.

[0044] In the above, the thickness of the outer copper foil is 0.5 oz.

[0045] (5) Drilling blind holes: First, perform LDD browning treatment on the inner layer board to increase the roughness of the outer copper foil and improve the absorption capacity of the copper foil to the laser. After LDD browning, control the thickness of the surface copper to 7-9μm. Then, use a laser to drill blind holes on the inner layer board that connect to the next outer layer circuit.

[0046] (6) Drilling: According to the existing mechanical drilling technology, drilling is carried out on the inner layer board according to the design requirements to drill through holes; then the inner layer board is de-brownened to remove the brown layer on the board surface.

[0047] (7) Copper plating: A thin layer of copper is deposited on the board surface and hole walls using chemical copper plating. The backlight test is level 10, and the copper plating thickness in the hole is 0.5μm.

[0048] (8) Full-board hole filling electroplating: Full-board hole filling electroplating is performed on the inner layer board to fill blind holes and plate copper layers on the walls of through holes.

[0049] In the above, during the whole board filling electroplating, the copper layer thickness of the hole wall of the through hole is plated to ≥20μm, and the copper thickness of the board surface layer is controlled at 35±5μm.

[0050] In another embodiment, during the full-board through-hole plating, the blind holes are plated separately. That is, the blind holes are plated first to fill the holes, and then the through holes are plated. During the second plating of the through holes, the clamping point position is reversed to reduce the current density and extend the plating time (relative to the parameters when plating the blind holes). That is, the current density when plating the through holes is less than the current density when plating the blind holes, ensuring that the copper thickness uniformity is within ±3μm. The through hole wall is plated to a copper thickness of ≥20μm with an average of 23μm, and the surface copper thickness is controlled at 35±5μm.

[0051] (9) Resin plugging: Resin plugging and curing are performed on the through holes.

[0052] (10) Grinding plate: The excess resin on the orifice and the plate surface is ground off by a ceramic grinding plate, and then the inner layer plate is ground twice in the warp and weft directions, that is, the inner layer plate is ground once in the long side direction and the short side direction respectively, to ensure that the physical tensile coefficient in the warp and weft directions is within a controllable range.

[0053] (11) Micro-etching: Micro-etching is performed on the inner layer board to reduce the copper thickness. Acid etching is used to reduce the surface copper thickness to 22±3μm, which facilitates the subsequent etching to create fine lines and avoids severe side etching and line etching failure due to excessive surface copper thickness.

[0054] (12) Fabrication of outer layer circuits (negative film process): outer layer pattern transfer, photosensitive film is coated using a vertical coating machine, the film thickness of the photosensitive film is controlled at 8μm, and the outer layer circuit is exposed using a fully automatic exposure machine with 5-6 exposure rulers (21 exposure rulers). After development, the outer layer circuit pattern is formed; outer layer etching, the outer layer circuit is etched from the inner layer board after exposure and development, and the outer layer line width is measured to be 3mil; outer layer AOI, and then check for defects such as open and short circuits, line gaps, and line pinholes in the outer layer circuit. Defective products are scrapped, and defect-free products are sent to the next process.

[0055] (13) Lamination: The inner layer board and the outer layer copper foil are laminated in sequence according to the requirements through the prepreg to form the outer layer board; wherein, the lamination sequence from top to bottom is the outer layer copper foil, prepreg, inner layer board, prepreg and outer layer copper foil.

[0056] In the above, the thickness of the outer copper foil is 0.5 oz.

[0057] (14) Drilling blind holes: First, perform LDD browning treatment on the outer layer board to increase the roughness of the outer copper foil and improve the absorption capacity of the copper foil to the laser. After LDD browning, control the thickness of the surface copper to 7-9μm. Then, use a laser to drill blind holes on the outer layer board that connect to the next outer layer circuit.

[0058] (15) Drilling: According to the existing mechanical drilling technology, drilling is carried out on the outer layer board according to the design requirements to drill through holes; then the outer layer board is de-brownened to remove the brown layer on the board surface.

[0059] (16) Copper plating: A thin layer of copper is deposited on the board surface and hole walls using chemical copper plating. The backlight test is level 10, and the copper plating thickness in the hole is 0.5μm.

[0060] (17) Full-board hole filling electroplating: Full-board hole filling electroplating is performed on the outer layer to fill blind holes and plate copper layers on the walls of through holes.

[0061] In the above, during the whole board filling electroplating, the copper layer thickness of the hole wall of the through hole is plated to ≥20μm, and the copper thickness of the board surface layer is controlled at 35±5μm.

[0062] In another embodiment, during the full-board through-hole plating, the blind holes are plated separately. That is, the blind holes are plated first to fill the holes, and then the through holes are plated. During the second plating of the through holes, the clamping point position is reversed to reduce the current density and extend the plating time (relative to the parameters when plating the blind holes). That is, the current density when plating the through holes is less than the current density when plating the blind holes, ensuring that the copper thickness uniformity is within ±3μm. The through hole wall is plated to a copper thickness of ≥20μm with an average of 23μm, and the surface copper thickness is controlled at 35±5μm.

[0063] (18) Resin plugging: Resin plugging and curing are performed on the through holes.

[0064] (19) Grinding plate: The excess resin on the orifice and the plate surface is ground off by a ceramic grinding plate, and then the outer layer plate is ground twice in the warp and weft directions, that is, the outer layer plate is ground once in the long side direction and once in the short side direction, to ensure that the physical tensile coefficient in the warp and weft directions is within a controllable range.

[0065] (20) Micro-etching: Micro-etching is performed on the outer layer to reduce copper thickness. Acid etching is used to reduce the surface copper thickness to 22±3μm, which facilitates subsequent etching to create fine lines and avoids severe side etching and line etching failure due to excessive surface copper thickness.

[0066] (21) Fabrication of outer layer circuits (negative film process): outer layer pattern transfer, photosensitive film is coated using a vertical coating machine, the film thickness of the photosensitive film is controlled at 8μm, and the outer layer circuit is exposed using a fully automatic exposure machine with 5-6 exposure rulers (21 exposure rulers). After development, the outer layer circuit pattern is formed; outer layer etching, the outer layer circuit is etched on the exposed and developed outer layer board, and the outer layer line width is measured to be 3mil; outer layer AOI, and then check for defects such as open circuits, short circuits, line gaps, and line pinholes in the outer layer circuit. Defective products are scrapped, and defect-free products are sent to the next process.

[0067] (22) Lamination: The outer layer board and the outer copper foil are laminated in sequence according to the requirements through the prepreg to form the production board; wherein, the lamination sequence from top to bottom is outer copper foil, prepreg, outer layer board, prepreg and outer copper foil.

[0068] In the above, the thickness of the outer copper foil is 0.5 oz.

[0069] (23) Drilling blind holes: First, perform LDD browning treatment on the production board to increase the roughness of the outer copper foil and improve the absorption capacity of the copper foil to the laser. After LDD browning, control the thickness of the surface copper to 7-9μm. Then, use a laser to drill blind holes on the production board that connect to the next outer layer circuit.

[0070] (24) Drilling: According to the existing mechanical drilling technology, drilling is carried out on the production board according to the design requirements to drill through holes; then the production board is de-brownened to remove the brown layer on the board surface.

[0071] (25) Copper plating: A thin layer of copper is deposited on the board surface and hole walls using chemical copper plating. The backlight test is level 10, and the copper plating thickness in the hole is 0.5μm.

[0072] (26) Full board filling electroplating: Full board filling electroplating is performed on the production board to fill blind holes and plate copper layers on the walls of through holes.

[0073] In the above, during the whole board filling electroplating, the copper layer thickness of the hole wall of the through hole is plated to ≥20μm, and the copper thickness of the board surface layer is controlled at 35±5μm.

[0074] In another embodiment, during the full-board through-hole plating, the blind holes are plated separately. That is, the blind holes are plated first to fill the holes, and then the through holes are plated. During the second plating of the through holes, the clamping point position is reversed to reduce the current density and extend the plating time (relative to the parameters when plating the blind holes). That is, the current density when plating the through holes is less than the current density when plating the blind holes, ensuring that the copper thickness uniformity is within ±3μm. The through hole wall is plated to a copper thickness of ≥20μm with an average of 23μm, and the surface copper thickness is controlled at 35±5μm.

[0075] (27) Resin plugging: Resin plugging and curing are performed on the through holes.

[0076] (28) Grinding plate: The excess resin on the orifice and plate surface is ground off by a ceramic grinding plate. Then, the production plate is ground twice in the warp and weft directions, that is, it is ground once along the long side and the short side of the production plate to ensure that the physical tensile coefficient in the warp and weft directions is within a controllable range.

[0077] (29) Micro-etching: Micro-etching is performed on the production board to reduce the copper thickness. Acid etching is used to reduce the surface copper thickness to 22±3μm, which facilitates the subsequent etching to create fine lines and avoids severe side etching and line etching failure due to excessive surface copper thickness.

[0078] (30) Fabrication of outer layer circuits (negative film process): outer layer pattern transfer, photosensitive film is coated using a vertical coating machine, the film thickness of the photosensitive film is controlled at 8μm, a fully automatic exposure machine is used, and the outer layer circuit is exposed with 5-6 exposure rulers (21 exposure rulers), and the outer layer circuit pattern is formed after development; outer layer etching, the outer layer circuit is etched on the exposed and developed production board, and the outer layer line width is measured to be 3mil; outer layer AOI, and then check for defects such as open and short circuits, line gaps, and line pinholes in the outer layer circuit. Defective products are scrapped, and defect-free products are sent to the next process.

[0079] In another embodiment, the expansion and contraction data of the outer layer of the first 5 PNL boards are measured, and the expansion and contraction coefficient of the outer layer circuit pattern is adjusted according to the actual expansion and contraction data. The solder mask is stretched according to the expansion and contraction coefficient of the outer layer circuit pattern. Both the circuit pattern and the solder mask are produced using a fully automatic exposure machine to ensure that the expansion and contraction tolerance requirement of ±0.05mm is met after reflow soldering.

[0080] (31) Solder resist and screen printing: After screen printing solder resist ink on the surface of the production board, it is then subjected to pre-curing, exposure, development and heat curing treatment in sequence to cure the solder resist ink into a solder resist layer; specifically, the solder resist ink on the TOP side and the characters on the TOP side are added with "UL mark", thereby coating a layer on the lines and substrates that do not need to be soldered to prevent bridging between lines during soldering, provide a permanent electrical environment and chemical corrosion resistance, and at the same time beautify the appearance.

[0081] (32) Surface treatment (immersion nickel and gold): The copper surface of the solder pads of the solder mask opening position is uniformly deposited with a nickel layer and a gold layer of a certain required thickness through chemical principle. The thickness of the nickel layer is 3-5μm; the thickness of the gold layer is 0.05-0.1μm.

[0082] (33) Electrical test: Test the electrical conductivity of the finished board. The test method used for this board is: flying probe test.

[0083] (34) Molding: Based on existing technology and according to design requirements, the shape is shaped with a tolerance of + / -0.05mm, and a high-order large-size laptop printed circuit board of the third stage is produced.

[0084] (35) FQC: Inspect the appearance of the printed circuit board according to the customer's acceptance standards and the applicant's inspection standards. If there are any defects, repair them in time to ensure excellent quality control for the customer.

[0085] (36)FQA: Re-test the appearance of the printed circuit board, the thickness of the through-hole copper, the thickness of the dielectric layer, the thickness of the solder mask, the thickness of the inner layer copper, etc. to see if they meet the customer's requirements.

[0086] (37) Packaging: The printed circuit boards are sealed according to the packaging method and quantity required by the customer, and desiccant and humidity card are placed in the packaging before shipment.

[0087] The technical solutions provided by the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the embodiments of the present invention. The descriptions of the embodiments above are only for helping to understand the principles of the embodiments of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the embodiments of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for manufacturing a high-order large-size notebook printed board, characterized by comprising the steps of: The method comprises the following steps: ​ S1, cutting out a yin-yang copper-clad core board according to the size of the board, wherein the thickness of the copper layer on the first surface is greater than that on the second surface; S2, laminating a film on the yin-yang copper-clad core board, then forming an inner layer circuit pattern on the first surface by exposure and development in sequence, the film on the second surface is exposed in whole, then etching the yin-yang copper-clad core board by a vacuum two-fluid etching machine, and removing the film to obtain the inner layer circuit on the first surface; S3, laminating a film on the yin-yang copper-clad core board, then forming an inner layer circuit pattern on the second surface by exposure and development in sequence, the film on the first surface is exposed in whole, then etching the yin-yang copper-clad core board by a vacuum two-fluid etching machine, and removing the film to obtain the inner layer circuit on the second surface; S4, laminating the yin-yang copper-clad core board and an outer layer copper foil according to requirements by prepreg to form an inner layer board; S5, drilling blind holes and through holes on the inner layer board in sequence, and then carrying out copper plating and whole board hole filling electroplating on the inner layer board to fill the blind holes and form a copper layer on the wall of the through holes; S6, resin plug is carried out on the through holes and is solidified, then the excess resin on the hole and the surface of the board is removed by grinding, and then the inner layer board is ground in the warp and weft directions again; S7, laminating a film on the inner layer board, then forming an outer layer circuit pattern on the inner layer board by exposure and development in sequence, and then etching the inner layer board by a vacuum two-fluid etching machine to obtain the outer layer circuit; S8, sequentially carrying out solder mask manufacturing, surface treatment and forming cutting on the inner layer board to obtain a printed board.

2. The method of claim 1, wherein the method further comprises: In step S1, the thickness of the copper layer on the first surface of the yin-yang copper-clad core board is 2oz, and the thickness of the copper layer on the second surface is 0.5oz.

3. The method of claim 2, wherein the method further comprises: In step S2, the etching factor during etching is greater than or equal to 3.

4. The method of claim 1, wherein the method further comprises: In step S1, a copper-clad core board with a copper thickness of 0.5oz on both surfaces is also cut out according to the size of the board, and then an inner layer circuit is manufactured on the copper-clad core board by laminating a film, exposure and development in sequence.

5. The method of claim 4, wherein the method further comprises: In step S4, two yin-yang copper-clad core boards, two copper-clad core boards and an outer layer copper foil are laminated according to requirements by prepreg to form an inner layer board; wherein the laminating order from top to bottom is outer layer copper foil, prepreg, yin-yang copper-clad core board, prepreg, copper-clad core board, prepreg, copper-clad core board, prepreg, yin-yang copper-clad core board, prepreg and outer layer copper foil, and the second surfaces of the upper and lower yin-yang copper-clad core boards are adjacent to the inner copper-clad core boards.

6. The method of claim 1-5, wherein, Between steps S7 and S8, the following steps are further included: S71, laminating the inner layer board and an outer layer copper foil according to requirements by prepreg to form an outer layer board; S72, drilling blind holes and through holes on the outer layer board in sequence, and then carrying out copper plating and whole board hole filling electroplating on the outer layer board to fill the blind holes and form a copper layer on the wall of the through holes; S73, resin plug is carried out on the through holes and is solidified, then the excess resin on the hole and the surface of the board is removed by grinding, and then the outer layer board is ground in the warp and weft directions again; S74, laminating a film on the outer layer board, then forming an outer layer circuit pattern on the outer layer board by exposure and development in sequence, and then etching the outer layer board by a vacuum two-fluid etching machine to obtain the outer layer circuit, thereby obtaining a second-order printed board.

7. The method of claim 6, wherein the method further comprises: Between step S74 and S8, the following steps are also included: S75, repeat steps S71 to S74 at least once, and finally make three and three or more printed boards.

8. The method of claim 7, wherein the method further comprises: Mechanical drilling is used for drilling through holes, and laser drilling is used for drilling blind holes. Before each laser drilling, the board is first subjected to LDD brown oxidation treatment. After LDD brown oxidation, the thickness of the surface copper layer is controlled at 7-9 μm. After each drilling of the through hole, the board is subjected to de-browning treatment.

9. The method of claim 7, wherein the method further comprises: When filling the holes of the whole plate with electroplating, the thickness of the hole wall copper layer of the through hole is plated to ≥20 μm, and the surface layer copper thickness of the plate is controlled at 35±5 μm.

10. The method of claim 7, wherein the method further comprises: After each longitudinal and latitudinal twice grinding of the plate, the plate is subjected to micro-etching and copper reduction to reduce the surface layer copper thickness of the plate to 22±3 μm.