Blind buried hole circuit board manufacturing method and circuit board thereof

Abstract

The invention provides a blind buried hole circuit board manufacturing method and a circuit board thereof. Relates to the technical field of circuit boards, in particular to a blind buried hole circuit board manufacturing method and a circuit board thereof. S2, cleaning the surface of the copper-clad plate, removing oil stains and an oxide layer, coating the surface of the copper-clad plate with a layer of photoresist, and transferring the designed inner-layer circuit pattern to the photoresist through an exposure machine; after developing treatment, the exposed part of the photoresist is reserved to form an anti-corrosion layer of the circuit; s3, putting the copper-clad plate into an etching solution to obtain a circuit part covered by the photoresist, and removing the photoresist to obtain an inner-layer circuit board; and S4, the inner-layer circuit board, the prepreg and the outer-layer copper foil are stacked and laminated. The blind and buried hole circuit board manufacturing method and the circuit board thereof have the advantages that operation is convenient, chips generated by punching are cleaned, and the blind and buried hole walls are electroplated uniformly.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit boards, and in particular to a method for manufacturing a blind buried via circuit board and the circuit board thereof. Background Art

[0002] With the development of electronic products towards being light, thin, short, and small, the layout density of electronic components has become higher, and the hole and line densities of the circuit boards carrying the electronic components have also become higher. Therefore, the blind buried via technology has emerged. The blind buried via technology realizes signal transmission without penetrating the entire PCB board by forming blind vias or buried vias in the inner layer, thereby saving valuable wiring space; this enables more signal lines to be wired in a limited space, improving the wiring density and the degree of freedom in design. Blind buried vias are widely used in the design of modern circuit boards and provide strong support for the development of circuit boards.

[0003] However, during the drilling process of the existing blind buried via circuit boards, debris will adhere to the hole walls, resulting in hindering the full contact between the electroplating solution and the blind buried via walls, causing phenomena such as uneven electroplating layers and insufficient thickness on the blind buried via walls, affecting the electrical conductivity and corrosion resistance of the circuit boards, and reducing the product quality.

[0004] Therefore, it is necessary to provide a method for manufacturing a blind buried via circuit board and the circuit board thereof to solve the above technical problems. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a method for manufacturing a blind buried via circuit board and the circuit board thereof, which is convenient to operate, can clean the debris generated during drilling, and make the electroplating on the blind buried via walls uniform.

[0006] To solve the above technical problems, the method for manufacturing a blind buried via circuit board and the circuit board thereof provided by the present invention includes: S1. Cutting the copper clad laminate into appropriate sizes; S2. Cleaning the surface of the copper clad laminate to remove oil stains and oxide layers, coating a layer of photoresist on the surface of the copper clad laminate, and transferring the designed inner layer circuit pattern onto the photoresist through an exposure machine; after developing, the exposed part of the photoresist remains to form the anti-etching layer of the circuit; S3. Placing the copper clad laminate in the etching solution to obtain the circuit part covered by the photoresist, and removing the photoresist to obtain the inner layer circuit board; S4. Stacking and laminating the inner layer circuit board with the prepreg and the outer copper foil to obtain a semi-finished circuit board; S5. Drilling the semi-finished circuit board through a drilling device, and successively performing electroless copper plating and electroplating on the drilled positions to obtain the finished blind buried via circuit board; The drilling device includes four support rods fixedly installed on the top of the placement plate. The tops of the four support rods are fixedly installed with a top plate. Two electric push rods are fixedly installed at the bottom of the top plate. First cross plates are fixedly installed on the output shafts of the two electric push rods respectively. A rotation motor is fixedly installed on the top of the first cross plate. The output shaft of the rotation motor penetrates through the first cross plate and is movably connected to the first cross plate. A drill rod is fixedly installed on the output shaft of the rotation motor. A water tank is fixedly installed on the top of the top plate. An air suction fan is fixedly installed at the bottom of the top plate. A telescopic bellows is fixedly installed at the air inlet of the air suction fan. The bottom end of the telescopic bellows is fixedly installed with two L-shaped pipes, and both of the two L-shaped pipes are fixedly connected to the first cross plate. Air collecting hoods are respectively fixedly installed at the bottom ends of the two L-shaped pipes. A connecting pipe is fixedly installed at the air outlet of the air suction fan, and the top end of the connecting pipe extends into the water tank and is hermetically connected to the water tank. An M-shaped pipe is fixedly installed at the top end of the connecting pipe. Two first fixing plates are fixedly installed in the M-shaped pipe. Rotating rods are respectively rotatably installed on the two first fixing plates. A plurality of stirring rods are respectively fixedly installed on the two rotating rods. Propellers are respectively fixedly installed at the top ends of the two rotating rods.

[0007] Preferably, a first annular plate and a second cross plate are fixedly installed in the M-shaped pipe, and the first annular plate is located above the second cross plate. A backflow prevention plate is arranged on the top of the first annular plate. Two elastic pull ropes are fixedly installed at the bottom of the backflow prevention plate, and the bottom ends of both of the two elastic pull ropes are fixedly connected to the second cross plate. Both of the two elastic pull ropes are slidably connected to the first annular plate.

[0008] Preferably, a fixing pipe is detachably installed on the top of the water tank. An activated carbon plate and a second annular plate are fixedly installed in the fixing pipe, and the activated carbon plate is located above the second annular plate. Two sliding rods are slidably installed on the second annular plate. Sealing circular plates are fixedly installed at the top ends of the two sliding rods.

[0009] Preferably, limiting plates are respectively fixedly installed at the bottom ends of the two sliding rods.

[0010] Preferably, rotation holes are respectively formed on the two first fixing plates. Rotation bearings are respectively fixedly installed in the two rotation holes. The two rotating rods respectively penetrate through the two rotation bearings and are respectively fixedly connected to the inner walls of the two rotation bearings.

[0011] Preferably, two through holes are formed on the first annular plate. Linear bearings are respectively fixedly installed in the two through holes. The two elastic pull ropes respectively penetrate through the two linear bearings and are respectively slidably connected to the inner walls of the two linear bearings.

[0012] Preferably, a sewage discharge pipe is fixedly installed on the water tank, and a control valve is arranged in the sewage discharge pipe.

[0013] A blind buried via circuit board is manufactured by using the above-mentioned manufacturing method of blind buried via circuit board.

[0014] Compared with the related art, the manufacturing method of blind buried via circuit board and the circuit board provided by the present invention have the following beneficial effects: The present invention provides a manufacturing method of blind buried via circuit board and the circuit board thereof. The semi-finished circuit board is placed on the placement board. The output shaft of the electric push rod extends to drive the drill rod to move downward to contact the semi-finished circuit board. The drill rod is rotated by the rotation of the rotating motor to drill the semi-finished circuit board. The suction fan works to generate a strong suction force, adsorbing the debris and toxic gases generated during the drilling process into the suction fan, preventing them from adhering to the hole wall, ensuring that the electroplating solution is in full contact with the blind buried via hole wall, and avoiding the phenomena of uneven electroplating layer and insufficient thickness on the blind buried via hole wall. Along with the high-pressure gas discharged by the suction fan, it enters the M-shaped pipe, pushing the anti-backflow plate upward to separate from the first annular plate and opening the M-shaped pipe. Then, the high-pressure gas continues to flow in the M-shaped pipe, causing the stirring rod to rotate, keeping the adsorbed water in the water tank in a flowing state all the time, and adsorbing the debris and water-soluble toxic gases more evenly. Thus, the utilization of the adsorbed water is maximized. The water-insoluble toxic gases are adsorbed by the activated carbon plate to prevent air pollution. When the suction fan is turned off, the elastic pull rope returns to its original state, pulling the anti-backflow plate back to the original position to closely contact the first annular plate, thereby blocking the M-shaped pipe and preventing the adsorbed water in the water tank from entering the suction fan and affecting the service life of the suction fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is the front view structural schematic diagram of the manufacturing method of blind buried via circuit board and the circuit board provided by the present invention; Figure 2 is Figure 1 the enlarged schematic diagram of part A shown in Figure 3 is Figure 2 the enlarged schematic diagram of part B shown in Figure 4 is Figure 2 the enlarged schematic diagram of part C shown in Figure 5 is Figure 2 the enlarged schematic diagram of part D shown in Figure 6 is Figure 1 the assembly drawing of the propeller and the stirring rod shown in Figure 7 is the front view of the manufacturing method of blind buried via circuit board and the circuit board provided by the present invention; Reference numerals in the figure: 1, placing board; 2, support rod; 3, top board; 4, electric push rod; 5, first horizontal board; 6, rotating motor; 7, drill rod; 8, L-shaped pipe; 9, air collecting hood; 10, telescopic bellows; 11, suction fan; 12, water tank; 13, M-shaped pipe; 14, stirring rod; 15, rotating rod; 16, propeller; 17, first fixing plate; 19, first annular plate; 20, anti-backflow plate; 21, second horizontal board; 22, elastic pull rope; 23, fixed pipe; 24, sealing round plate; 25, second annular plate; 26, sliding rod; 27, limiting plate; 28, activated carbon plate. Specific implementation manner

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] Please refer to Figures 1-7 , in the embodiment of the present invention, the production of blind buried via circuit boards includes the following steps; S1, cutting the copper clad laminate into appropriate sizes; S2, cleaning the surface of the copper clad laminate to remove oil stains and oxide layers, coating a layer of photoresist on the surface of the copper clad laminate, and transferring the designed inner layer circuit pattern to the photoresist through an exposure machine; after development treatment, the exposed part of the photoresist is retained to form an anti-etching layer of the circuit; S3, putting the copper clad laminate into the etching solution to obtain the circuit part covered by the photoresist, removing the photoresist to obtain the inner layer circuit board; S4, stacking and laminating the inner layer circuit board with prepreg and outer copper foil to obtain a circuit board semi-finished product; S5, drilling the circuit board semi-finished product through a drilling device, and sequentially performing copper deposition and electroplating treatment on the drilled positions to obtain a finished blind buried via circuit board; The drilling device includes four support rods 2 fixedly installed on the top of the placement plate 1. The tops of the four support rods 2 are fixedly installed with a top plate 3. The bottom of the top plate 3 is fixedly installed with two electric push rods 4. First cross plates 5 are respectively fixedly installed on the output shafts of the two electric push rods 4. A rotating motor 6 is fixedly installed on the top of the first cross plate 5. The output shaft of the rotating motor 6 penetrates through the first cross plate 5 and is movably connected to the first cross plate 5. A drill rod 7 is fixedly installed on the output shaft of the rotating motor 6. A water tank 12 is fixedly installed on the top of the top plate 3. In order to discharge the sewage in the water tank 12 that adsorbs debris out of the water tank 12, a sewage discharge pipe is fixedly installed on the water tank 12, and a control valve is arranged in the sewage discharge pipe. A suction fan 11 is fixedly installed on the bottom of the top plate 3. A telescopic bellows 10 is fixedly installed at the air inlet of the suction fan 11. The bottom end of the telescopic bellows 10 is fixedly installed with two L-shaped pipes 8, and both of the two L-shaped pipes 8 are fixedly connected to the first cross plate 5. Collection hoods 9 are respectively fixedly installed at the bottom ends of the two L-shaped pipes 8. Through the operation of the suction fan 11 to generate a strong suction force, the debris and toxic gases generated during the drilling process are adsorbed into the suction fan 11, preventing them from adhering to the hole wall, ensuring that the electroplating solution is in full contact with the blind buried hole wall, and avoiding the phenomena of uneven electroplating layer and insufficient thickness on the blind buried hole wall. A connecting pipe is fixedly installed at the air outlet of the suction fan 11, and the top end of the connecting pipe extends into the water tank 12 and is hermetically connected to the water tank 12. An M-shaped pipe 13 is fixedly installed at the top end of the connecting pipe. Two first fixing plates 17 are fixedly installed in the M-shaped pipe 13. Rotating rods 15 are respectively rotatably installed on the two first fixing plates 17. A plurality of stirring rods 14 are respectively fixedly installed on the two rotating rods 15. Propellers 16 are respectively fixedly installed at the top ends of the two rotating rods 15. The continuous flow of high-pressure gas in the M-shaped pipe 13 causes the stirring rods 14 to rotate, keeping the adsorbed water in the water tank 12 always in a flowing state, so that the adsorption of debris and water-soluble toxic gases is more uniform, and thus the utilization of the adsorbed water is maximized.

[0018] In order to prevent the reverse flow phenomenon in the M-shaped pipe 13 when the suction fan 11 is turned off, and prevent the adsorbed water in the water tank 12 from entering the suction fan 11 and affecting the service life of the suction fan 11, a first annular plate 19 and a second cross plate 21 are fixedly installed in the M-shaped pipe 13, and the first annular plate 19 is located above the second cross plate 21. A backflow prevention plate 20 is arranged on the top of the first annular plate 19. Two elastic pull ropes 22 are fixedly installed at the bottom of the backflow prevention plate 20, and the bottom ends of both of the two elastic pull ropes 22 are fixedly connected to the second cross plate 21. Both of the two elastic pull ropes 22 are slidably connected to the first annular plate 19. In order to reduce the friction between the elastic pull ropes 22 and the first annular plate 19, thereby reducing the wear degree of the elastic pull ropes 22 and improving the service life of the elastic pull ropes 22, two through holes are opened on the first annular plate 19. Linear bearings are respectively fixedly installed in the two through holes. The two elastic pull ropes 22 respectively penetrate through the two linear bearings and are respectively slidably connected to the inner walls of the two linear bearings.

[0019] In order to absorb the water-insoluble toxic gas generated during the drilling process and prevent the water-insoluble toxic gas from being directly discharged into the atmosphere, causing air pollution, a fixed pipe 23 is detachably installed at the top of the water tank 12. An activated carbon plate 28 and a second annular plate 25 are fixedly installed in the fixed pipe 23, and the activated carbon plate 28 is located above the second annular plate 25. Two sliding rods 26 are slidably installed on the second annular plate 25. In order to limit the sliding rods 26 and make the sliding rods 26 always slidably installed on the second annular plate 25 to prevent the sliding rods 26 from falling off the second annular plate 25, causing unnecessary trouble, limit plates 27 are fixedly installed at the bottom ends of the two sliding rods 26 respectively, and a sealing circular plate 24 is fixedly installed at the top ends of the two sliding rods 26.

[0020] In order to rotatably install the rotating rod 15 on the first fixing plate 17, rotating holes are respectively formed in the two first fixing plates 17, rotating bearings are respectively fixedly installed in the two rotating holes, and the two rotating rods 15 respectively penetrate through the two rotating bearings and are fixedly connected to the inner walls of the two rotating bearings respectively. Through the rotating bearings, the rotating rod 15 rotates more stably on the first fixing plate 17.

[0021] The manufacturing method of the blind buried via circuit board provided by the present invention and the working principle of the circuit board are as follows: In the initial state, the elastic pull rope 22 is in a stretched state, the anti-backflow plate 20 is closely attached to the first annular plate 19, the water tank 12 is filled with adsorbed water, and the outlet of the M-shaped pipe 13 is located below the liquid level of the adsorbed water. When drilling the circuit board semi-finished product is required, the circuit board semi-finished product is placed on the placement plate 1, the electric push rod 4 is started, the output shaft of the electric push rod 4 extends to drive the first cross plate 5 to move downward, the first cross plate 5 moves downward to drive the rotating motor 6 and the drill rod 7 to move downward to contact the circuit board semi-finished product, the rotating motor 6 is started, and the rotating motor 6 rotates to drive the drill rod 7 to rotate to drill the circuit board semi-finished product. At the same time, the suction fan 11 is started, and the suction fan 11 generates a strong suction force to adsorb the debris and toxic gases generated during the drilling process into the air collecting hood 9, preventing them from adhering to the hole wall, so that the electroplating solution can fully contact the blind buried via wall, avoiding the phenomenon of uneven electroplating layer and insufficient thickness on the blind buried via wall. Finally, the debris and toxic gases enter the telescopic bellows 10 and enter the M-shaped pipe 13 together with the high-pressure gas discharged from the air outlet of the suction fan 11. At this moment, the thrust generated by the high-pressure gas is greater than the elastic force of the elastic pull rope 22, and the high-pressure gas will push the anti-backflow plate 20 to move upward and separate from the first annular plate 19, thereby opening the M-shaped pipe 13. Then, the high-pressure gas continues to flow in the M-shaped pipe 13 to push the propeller 16 to rotate, the propeller 16 rotates to drive the rotating rod 15 to rotate, and the rotating rod 15 rotates to drive the stirring rod 14 to rotate, so that the adsorbed water in the water tank 12 is always in a flowing state, adsorbing the debris and water-soluble toxic gases more evenly, thereby maximizing the utilization of the adsorbed water. The water-insoluble toxic gases will separate from the adsorbed water to the upper part of the liquid level, increasing the air pressure in the water tank 12. Under the action of the air pressure, the sealing circular plate 24 is pushed upward to separate from the second annular plate 25, opening the fixed pipe 23, so that the water-insoluble toxic gases contact the activated carbon plate 28, and the activated carbon plate 28 adsorbs the water-insoluble toxic gases to prevent air pollution. When the drilling of the circuit board semi-finished product is completed and the suction fan 11 is turned off, at this moment, the suction fan 11 no longer generates high-pressure gas, and the elastic pull rope 22 will return to its original state and pull the anti-backflow plate 20 back to the original position to closely contact the first annular plate 19, thereby blocking the M-shaped pipe 13. When the suction fan 11 is turned off, a backflow phenomenon occurs in the M-shaped pipe 13 to block the M-shaped pipe 13, preventing the adsorbed water in the water tank 12 from entering the suction fan 11 and affecting the service life of the suction fan 11.

[0022] Compared with the related technology, the blind buried via circuit board manufacturing method and the circuit board provided by the present invention have the following beneficial effects: Place the semi-finished circuit board on the placement board 1. The output shaft of the electric push rod 4 extends to drive the drill rod 7 to move downward and contact the semi-finished circuit board. The drill rod 7 is rotated by the rotation of the rotation motor 6 to perform drilling operations on the semi-finished circuit board. The suction fan 11 works to generate a strong suction force, adsorbing the debris and toxic gases generated during the drilling process into the suction fan 11, preventing them from adhering to the hole wall, ensuring that the electroplating solution comes into full contact with the blind buried hole wall, and avoiding the phenomena of uneven electroplating layer and insufficient thickness on the blind buried hole wall. Along with the high-pressure gas discharged from the suction fan 11, it enters the M-shaped pipe 13, pushing the anti-backflow plate 20 to move upward and separate from the first annular plate 19 to open the M-shaped pipe 13. Then, the high-pressure gas continues to flow in the M-shaped pipe 13, causing the stirring rod 14 to rotate, keeping the adsorbed water in the water tank 12 in a flowing state, and making the adsorption of debris and water-soluble toxic gases more uniform. Thus, the utilization of the adsorbed water is maximized. The water-insoluble toxic gases are adsorbed by the activated carbon plate 28 to prevent air pollution. When the suction fan 11 is turned off, the elastic pull rope 22 returns to its original state, pulling the anti-backflow plate 20 back to its original position and tightly contacting the first annular plate 19, thereby blocking the M-shaped pipe 13 and preventing the adsorbed water in the water tank 12 from entering the suction fan 11 and affecting the service life of the suction fan 11.

[0023] The present invention also provides a blind buried hole circuit board, which is manufactured by using the above-mentioned manufacturing method of the blind buried hole circuit board.

[0024] The above are only the embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. A method for manufacturing a blind buried via circuit board, characterized in that, Including the following steps; S1. Cut the copper clad laminate into appropriate sizes; S2. Clean the surface of the copper clad laminate to remove oil stains and oxide layers. Coat a layer of photoresist on the surface of the copper clad laminate. Transfer the designed inner layer circuit pattern onto the photoresist through an exposure machine; After developing, the exposed part of the photoresist remains to form an anti-etching layer for the circuit; S3. Place the copper clad laminate in the etching solution to obtain the circuit part covered by the photoresist, and remove the photoresist to obtain the inner layer circuit board; S4. Stack and press the inner layer circuit board, prepreg, and outer copper foil together to obtain a semi-finished circuit board; S5. Drill the semi-finished circuit board through a drilling device, and perform electroless copper plating and electroplating treatments on the drilled positions in sequence to obtain a finished blind and buried via circuit board; The drilling device includes four support rods fixedly installed on the top of a placement plate. The tops of the four support rods are fixedly installed with a top plate. Two electric push rods are fixedly installed at the bottom of the top plate. First cross plates are respectively fixedly installed on the output shafts of the two electric push rods. A rotating motor is fixedly installed on the top of the first cross plate, and the output shaft of the rotating motor penetrates through the first cross plate and is movably connected to the first cross plate. A drill rod is fixedly installed on the output shaft of the rotating motor. A water tank is fixedly installed on the top of the top plate. An air suction fan is fixedly installed at the bottom of the top plate. A telescopic bellows is fixedly installed at the air inlet of the air suction fan. The bottom end of the telescopic bellows is fixedly installed with two L-shaped pipes, and both of the two L-shaped pipes are fixedly connected to the first cross plate. Air collecting hoods are respectively fixedly installed at the bottom ends of the two L-shaped pipes. A connecting pipe is fixedly installed at the air outlet of the air suction fan, and the top end of the connecting pipe extends into the water tank and is hermetically connected to the water tank. An M-shaped pipe is fixedly installed at the top end of the connecting pipe. Two first fixing plates are fixedly installed in the M-shaped pipe. Rotating rods are respectively rotatably installed on the two first fixing plates. A plurality of stirring rods are respectively fixedly installed on the two rotating rods. Propellers are respectively fixedly installed at the top ends of the two rotating rods.

2. The method for manufacturing a blind buried via circuit board according to claim 1, wherein, A first annular plate and a second cross plate are fixedly installed in the M-shaped pipe, and the first annular plate is located above the second cross plate. A backflow prevention plate is arranged on the top of the first annular plate. Two elastic pull ropes are fixedly installed at the bottom of the backflow prevention plate, and the bottom ends of both of the two elastic pull ropes are fixedly connected to the second cross plate. Both of the two elastic pull ropes are slidably connected to the first annular plate.

3. The method for manufacturing a blind buried via circuit board according to claim 2, wherein A fixing pipe is detachably installed on the top of the water tank. An activated carbon plate and a second annular plate are fixedly installed in the fixing pipe, and the activated carbon plate is located above the second annular plate. Two sliding rods are slidably installed on the second annular plate. Sealing round plates are fixedly installed at the top ends of the two sliding rods.

4. The method for manufacturing a blind buried via circuit board according to claim 3, wherein Limit plates are respectively fixedly installed at the bottom ends of the two sliding rods.

5. The method for manufacturing a blind buried via circuit board according to claim 4, characterized in that, Rotating holes are respectively opened on the two first fixing plates. Rotating bearings are respectively fixedly installed in the two rotating holes. The two rotating rods respectively penetrate through the two rotating bearings and are respectively fixedly connected to the inner walls of the two rotating bearings.

6. The method for manufacturing a blind buried via circuit board according to claim 5, wherein, Two through holes are formed in the first annular plate, and linear bearings are fixedly installed in the two through holes respectively. The two elastic ropes respectively penetrate through the two linear bearings and are respectively slidably connected with the inner walls of the two linear bearings.

7. The method for manufacturing a blind buried via circuit board according to claim 6, characterized in that, A sewage discharge pipe is fixedly installed on the water tank, and a control valve is arranged in the sewage discharge pipe.

8. A blind buried via circuit board, characterized in that, It is manufactured by using the method for manufacturing a blind buried hole circuit board according to any one of claims 1-7.

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