Manufacturing method of printed circuit board and printed circuit board

Abstract

The invention discloses a manufacturing method of a printed circuit board and the printed circuit board, and the method comprises the steps: exposing and removing a part, corresponding to a first blind hole, of a dry film on a double-sided board, so as to form a second blind hole; plating a copper / tin column in the second blind hole; a third blind hole is drilled in the part, corresponding to the cylinder part, of the first prepreg, so that a middle-layer plate is obtained; a fourth blind hole is drilled in the part, corresponding to the cylinder part, of the second prepreg, so that an upper-layer plate is obtained; and at least any two of the upper-layer plate, the middle-layer plate and the lower-layer plate are stacked in the vertical direction and connected in a press fit mode. Therefore, at least any two of the upper-layer plate, the middle-layer plate and the lower-layer plate can be stacked in the vertical direction and are mutually pressed and connected to form the printed circuit board, so that the pressing times of the printed circuit board in the manufacturing process can be reduced, and the layers can be electrically connected through copper / tin columns; and the connection stability and reliability can be improved.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board technology, and in particular to a method for manufacturing a printed circuit board and a printed circuit board. Background Technology

[0002] As electronic products become increasingly integrated and denser, PCBs (printed circuit boards) are also undergoing in-depth research and development in the direction of high-density design and processing.

[0003] With the trend towards miniaturization and multi-functionality in PCB products, PCB designs are becoming increasingly high-density. Most existing PCBs employ a multi-layer lamination process, which, due to the high number of layers, often results in long processing flows, long delivery cycles, and low yields. Some PCBs are manufactured using sintering, which, while reducing process steps and time, suffers from limitations, making high-density boards prone to short circuits due to plating defects, leading to questionable yields. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one object of the present invention is to provide a method for manufacturing a printed circuit board, which simplifies the manufacturing process and enables the manufactured printed circuit board to have a stable and reliable structure.

[0005] The present invention further proposes a printed circuit board.

[0006] The method for manufacturing a printed circuit board according to the present invention includes: preparing a double-sided board, wherein the double-sided board includes a dielectric layer and a plurality of copper pillar pads, each copper pillar pad includes a pillar portion and a pad portion, the pillar portion penetrates the dielectric layer, the pad portion is connected to both ends of the pillar portion and is located above and below the dielectric layer, and the plurality of copper pillar pads are spaced apart from each other; applying an ABF film to the top surface of the prepared double-sided board; drilling a first blind hole in the portion of the ABF film corresponding to the pillar portion, and flash-plating a conductive copper layer on the upper side of the ABF film and the portion corresponding to the sidewall of the first blind hole; applying a dry film to both the upper and lower surfaces of the double-sided board after flash-plating the conductive copper layer, and applying a dry film to the upper and lower surfaces of the double-sided board on the upper and lower surfaces of the double-sided board after flash-plating the conductive copper layer. The portion of the film corresponding to the first blind hole is exposed and removed to form a second blind hole; copper / tin pillars are plated in the second blind hole, and the dry films on the upper and lower surfaces are removed, and the conductive copper layer on the upper side of the ABF film is removed to obtain a lower layer board; a first prepreg is attached to the lower layer board, and a third blind hole is drilled in the portion of the first prepreg corresponding to the pillar portion to obtain a middle layer board; a second prepreg is attached to the lower surface of the prepared double-sided board, and a fourth blind hole is drilled in the portion of the second prepreg corresponding to the pillar portion to obtain an upper layer board; at least two of the upper layer board, the middle layer board, and the lower layer board are stacked and pressed together in the vertical direction.

[0007] Therefore, at least two of the upper, middle, and lower layers can be stacked vertically and pressed together to form a printed circuit board. This not only reduces the number of pressing operations during the manufacturing process, but also improves the stability and reliability of the connection by electrically connecting the layers through copper / tin pillars.

[0008] In some examples of the present invention, the step of stacking and pressing together any at least two of the upper layer board, the middle layer board, and the lower layer board in the vertical direction includes: stacking and pressing together the upper layer board, the middle layer board, and the lower layer board in the vertical direction, wherein the copper / tin pillar of the middle layer board corresponds to the fourth blind via, and the copper / tin pillar of the lower layer board corresponds to the third blind via.

[0009] In some examples of the present invention, the step of stacking and pressing the upper layer board, the middle layer board, and the lower layer board in the vertical direction, wherein the copper / tin pillars of the middle layer board correspond to the fourth blind via, and the copper / tin pillars of the lower layer board correspond to the third blind via, includes: there are multiple middle layer boards, the multiple middle layer boards are stacked in the vertical direction, the copper / tin pillar of one of two adjacent middle layer boards corresponds to the third blind via of the other, the copper / tin pillar of the uppermost of the multiple middle layer boards corresponds to the fourth blind via, and the third blind via of the lowermost of the multiple middle layer boards corresponds to the copper / tin pillar of the lower layer board.

[0010] In some examples of the present invention, the step of plating copper / tin pillars in the third blind hole, removing the dry film on the upper and lower surfaces, and removing the conductive copper layer on the upper side of the ABF film to obtain the lower board further includes: making the copper / tin pillars protrude from the upper side of the ABF film, and setting the length of the portion of the copper / tin pillars protruding from the upper side of the ABF film in the vertical direction as L1, where L1 satisfies the relationship: 20μm≤L1≤40μm.

[0011] In some examples of the present invention, the copper / tin pillar includes a copper pillar and a tin pillar, the tin pillar being located above the copper pillar, and the thickness of the tin pillar being less than the thickness of the copper pillar.

[0012] In some examples of the present invention, the step of applying an ABF film to the top of the prepared double-sided panel includes: the ABF film covering the top of the dielectric layer and the pad portion located on the dielectric layer.

[0013] In some examples of the present invention, the step of drilling a first blind hole in the portion of the ABF film corresponding to the column portion, and flash-plating a conductive copper layer on the upper side of the ABF film and the portion corresponding to the sidewall of the first blind hole includes: setting the thickness of the conductive copper layer to L2, where L2 satisfies the relationship: 1μm≤L2≤2μm.

[0014] In some examples of the present invention, the step of attaching dry film to both the upper and lower surfaces of the double-sided panel on which the conductive copper layer has been flash-plated, and exposing and removing the portion of the dry film on the upper surface of the double-sided panel corresponding to the first blind hole to form a second blind hole includes: exposing and removing the portion of the dry film on the upper surface of the double-sided panel corresponding to the first blind hole to form a first through hole, the first through hole corresponding to and communicating with the first blind hole to form a second blind hole, and the width of the first through hole being greater than the width of the first blind hole.

[0015] In some examples of the present invention, the distance between two adjacent copper pillar pads in the double-sided board is set to L3, and L3 satisfies the relationship: 0.08mm≤L3≤0.12mm.

[0016] The printed circuit board according to the present invention is applicable to the above-described method for manufacturing the printed circuit board.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart of a method for manufacturing a printed circuit board according to an embodiment of the present invention; Figure 2 This is a manufacturing process diagram of the lower layer plate according to an embodiment of the present invention; Figure 3 This is a manufacturing process diagram of the middle layer plate according to an embodiment of the present invention; Figure 4 This is a manufacturing process diagram of the upper plate according to an embodiment of the present invention; Figure 5 This is an exploded view of a printed circuit board according to an embodiment of the present invention; Figure 6 This is a schematic diagram of a printed circuit board according to an embodiment of the present invention.

[0019] Figure label: 100. Printed circuit boards; 10. Double-sided board; 11. Dielectric layer; 12. Copper pillar pad; 121. Pillar section; 122. Pad section; 13. ABF film; 14. First blind via; 15. Conductive copper layer; 16. Second blind via; 17. Copper / tin pillar; 18. Lower layer board; 19. Dry film; 20. First prepreg; 21. Third blind hole; 22. Middle layer board; 30. Second prepreg; 31. Fourth blind hole; 32. Upper plate. Detailed Implementation

[0020] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0021] The following is for reference. Figures 1-6 A method for manufacturing a printed circuit board 100 according to an embodiment of the present invention is described, which can produce the printed circuit board 100.

[0022] Combination Figures 1-6 As shown, the manufacturing method of the printed circuit board 100 according to the present invention mainly includes the following steps: S1. Prepare a double-sided panel 10, wherein the double-sided panel 10 includes a dielectric layer 11 and a plurality of copper pillar pads 12. The copper pillar pads 12 include a pillar portion 121 and a pad portion 122. The pillar portion 121 passes through the dielectric layer 11. The pad portion 122 is connected to both ends of the pillar portion 121 and is located above and below the dielectric layer 11. The plurality of copper pillar pads 12 are spaced apart from each other. S2. Attach ABF film 13 to the prepared double-sided panel 10; S3. Drill a first blind hole 14 into the portion of ABF film 13 corresponding to the column portion 121, and flash plate a conductive copper layer 15 onto the upper side of ABF film 13 and the portion corresponding to the sidewall of the first blind hole 14. S4. Dry film 19 is applied to both the upper and lower surfaces of the double-sided panel 10 that has been flash-plated with conductive copper layer 15, and the portion of the dry film 19 on the upper surface of the double-sided panel 10 corresponding to the first blind hole 14 is exposed and removed to form the second blind hole 16. S5. Plating copper / tin pillars 17 in the second blind hole 16, removing the dry film 19 on the upper and lower surfaces, and removing the conductive copper layer 15 on the upper side of the ABF film 13 to obtain the lower board 18. S6. A first prepreg 20 is attached to the bottom of the lower plate 18, and a third blind hole 21 is drilled in the part of the first prepreg 20 corresponding to the column part 121 to obtain the middle plate 22. S7. Attach the second semi-cured sheet 30 to the bottom of the prepared double-sided panel 10, and drill a fourth blind hole 31 in the part of the second semi-cured sheet 30 corresponding to the column part 121 to obtain the upper plate 32. S8. Stack any two of the upper plate 32, the middle plate 22 and the lower plate 18 in the vertical direction and press them together.

[0023] Specifically, an ABF film 13, which is an epoxy resin film, is applied to the top of the prepared double-sided panel 10. In some embodiments of the present invention, pure adhesive is applied to the top of the prepared double-sided panel 10. Further, a first blind hole 14 is laser-drilled into the portion of the ABF film 13 corresponding to the pillar portion 121. In some embodiments of the present invention, the diameter of the first blind hole 14 can be 50 μm. Further, a conductive copper layer 15 is flash-plated onto the upper side of the ABF film 13 and the portion corresponding to the sidewall of the first blind hole 14. The conductive copper layer 15 can... The dry film 19 serves as an electrical conductor, preparing for the subsequent electroplating of copper and tin pillars. Dry films 19 are applied to both the upper and lower surfaces of the double-sided board 10, which has been flash-plated with a conductive copper layer 15. The dry film 19 can act as a plating resist. The portion of the dry film 19 on the upper surface of the double-sided board 10 corresponding to the first blind hole 14 is exposed and removed to form a second blind hole 16. Then, copper / tin pillars 17 are plated inside the second blind hole 16. In some embodiments of the present invention, the copper / tin pillars 17 will protrude from the dry film 19. The dry films 19 on both the upper and lower surfaces are removed, and the conductive copper layer 15 on the upper side of the ABF film 13 is removed to obtain the lower board 18.

[0024] In some embodiments of the present invention, based on the lower plate 18, a first prepreg 20 is attached to the underside of the lower plate 18, and a third blind hole 21 is drilled in the portion of the first prepreg 20 corresponding to the column portion 121 to obtain the middle plate 22.

[0025] In some embodiments of the present invention, after the double-sided panel 10 is prepared, a second prepreg 30 can be attached to the underside of the double-sided panel 10, and a fourth blind hole 31 can be drilled in the part of the second prepreg 30 corresponding to the column part 121 to obtain the upper plate 32.

[0026] Since the copper / tin pillars 17 of the middle layer board 22 and the lower layer board 18 are located on top, at least two of the upper layer board 32, the middle layer board 22 and the lower layer board 18 are stacked and pressed together in the vertical direction.

[0027] In some embodiments of the present invention, when the upper plate 32 and the middle plate 22 are stacked in the vertical direction, the copper / tin pillars 17 on the middle plate 22 can be pressed together with the fourth blind hole 31 on the upper plate 32.

[0028] In other embodiments of the present invention, when the lower layer board 18 and the middle layer board 22 are stacked in the vertical direction, the copper / tin pillars 17 of the lower layer board 18 can be pressed together with the third blind hole 21 of the middle layer board 22.

[0029] In other embodiments of the present invention, when the upper plate 32 and the lower plate 18 are stacked in the vertical direction, the copper / tin pillars 17 of the lower plate 18 are pressed together with the third blind hole 21 of the middle plate 22.

[0030] In some other embodiments of the present invention, the upper plate 32, the middle plate 22 and the lower plate 18 are stacked and pressed together in the vertical direction, wherein the copper / tin pillars 17 of the middle plate 22 correspond to the fourth blind hole 31 and the copper / tin pillars 17 of the lower plate 18 correspond to the third blind hole 21.

[0031] The steps of stacking and pressing together the upper layer board 32, the middle layer board 22, and the lower layer board 18 in the vertical direction, wherein the copper / tin pillars 17 of the middle layer board 22 correspond to the fourth blind via 31, and the copper / tin pillars 17 of the lower layer board 18 correspond to the third blind via 21, include: There are multiple middle layer boards 22, which are stacked in the vertical direction. The copper / tin pillar 17 of one of two adjacent middle layer boards 22 corresponds to the third blind hole 21 of the other. The copper / tin pillar 17 of the uppermost middle layer board 22 corresponds to the fourth blind hole 31. The third blind hole 21 of the lowermost middle layer board 22 corresponds to the copper / tin pillar 17 of the lower layer board 18.

[0032] In some embodiments of the present invention, the upper layer board 32, the middle layer board 22 and the lower layer board 18 are stacked and pressed together in the vertical direction. The steps of having the copper / tin pillar 17 of the middle layer board 22 correspond to the fourth blind hole 31 and the copper / tin pillar 17 of the lower layer board 18 correspond to the third blind hole 21 include: there are multiple middle layer boards 22, the multiple middle layer boards 22 are stacked in the vertical direction, the copper / tin pillar 17 of one of two adjacent middle layer boards 22 corresponds to the third blind hole 21 of the other, the copper / tin pillar 17 of the uppermost of the multiple middle layer boards 22 corresponds to the fourth blind hole 31, and the third blind hole 21 of the lowermost of the multiple middle layer boards 22 corresponds to the copper / tin pillar 17 of the lower layer board 18.

[0033] In some embodiments of the present invention, the steps of plating copper / tin pillars 17 in the third blind hole 21, removing the dry films 19 on the upper and lower surfaces, and removing the conductive copper layer 15 on the upper side of the ABF film 13 to obtain the lower plate 18 further include: making the copper / tin pillars 17 protrude from the upper side of the ABF film 13, and setting the length of the portion of the copper / tin pillars 17 protruding from the upper side of the ABF film 13 in the vertical direction as L1, where L1 satisfies the relationship: 20μm≤L1≤40μm, thereby ensuring that the copper / tin pillars 17 extend into the blind hole and that the copper / tin pillars 17 are connected and fixed stably and reliably to the blind hole, while preventing the copper / tin pillars 17 from being too long and the structure from being unstable.

[0034] In some embodiments of the present invention, the copper / tin pillar 17 includes a copper pillar and a tin pillar, with the tin pillar located above the copper pillar and the thickness of the tin pillar being less than the thickness of the copper pillar.

[0035] Specifically, by placing the tin pillar on top of the copper pillar, and making the tin pillar thinner than the copper pillar, the copper / tin pillar 17 retains the high electrical and thermal conductivity of copper, enabling efficient transmission of large currents and rapid heat dissipation. This is particularly suitable for high-power applications such as new energy and industrial control. The tin pillar's location on top of the copper pillar allows for rapid fusion with the solder (such as tin-lead or lead-free solder) during the soldering process, forming a stable solder interface. This solves the problems of "difficult soldering" and "cold solder joints" caused by oxidation of pure copper surfaces, significantly improving connection reliability.

[0036] Combination Figure 2 As shown, the step of attaching ABF film 13 to the top of the prepared double-sided panel 10 includes: ABF film 13 covering the top of the dielectric layer 11 and the pad portion 122 located on the dielectric layer 11.

[0037] In some embodiments of the present invention, the step of drilling a first blind hole 14 in the portion of the ABF film 13 corresponding to the column portion 121, and flash-plating a conductive copper layer 15 on the upper side of the ABF film 13 and the portion corresponding to the sidewall of the first blind hole 14 includes: setting the thickness of the conductive copper layer 15 to L2, where L2 satisfies the relationship: 1μm≤L2≤2μm. This can prevent the conductive copper layer 15 from being too thick, thus affecting the subsequent production process of the printed circuit board 100, while ensuring the conductivity stability of the conductive copper layer 15.

[0038] Combination Figure 2 As shown, the steps of applying dry film 19 to both the upper and lower surfaces of the double-sided panel 10 after flash plating conductive copper layer 15, and partially exposing and removing the dry film 19 on the upper surface of the double-sided panel 10 corresponding to the first blind hole 14 to form the second blind hole 16 include: partially exposing and removing the dry film 19 on the upper surface of the double-sided panel 10 corresponding to the first blind hole 14 to form a first through hole, the first through hole corresponding to the first blind hole 14 and communicating to form the second blind hole 16, the width of the first through hole being greater than the width of the first blind hole 14.

[0039] In some embodiments of the present invention, the distance between two adjacent copper pillar pads 12 in the double-sided board 10 is set to L3, and L3 satisfies the relationship: 0.08mm≤L3≤0.12mm. This allows for a higher density of copper pillar pads 12 on the double-sided board 10. By using a double-sided board 10 with a higher density to manufacture the printed circuit board 100, the size of the printed circuit board 100 can be reduced while ensuring the functionality of the printed circuit board 100. Furthermore, through the one-time lamination manufacturing method of the present invention, the printed circuit board 100 manufactured by the double-sided board 10 with a higher density is less prone to short circuits and has a higher yield.

[0040] Furthermore, in some embodiments of the present invention, the steps for preparing the double-sided panel 10 include: preparing a copper-clad laminate with a thin copper layer of 3-5 μm, wherein the thin copper layer of 3-5 μm is located on both sides of the dielectric layer 11, the thickness of the dielectric layer 11 is between 0.05 mm and 0.2 mm, drilling through holes in the copper-clad laminate, forming a conductive layer in the laser-drilled through holes, exposing the patterned area by applying a dry film 19, filling the through holes with copper, removing the dry film 19 to expose the remaining copper layers on both sides of the dielectric layer 11, and connecting the copper layers with the copper in the through holes to form a double-sided panel 10 with copper pillar pads 12.

[0041] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0043] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for manufacturing a printed circuit board, characterized in that, Includes the following steps: A double-sided panel (10) is prepared, wherein the double-sided panel (10) includes a dielectric layer (11) and a plurality of copper pillar pads (12). The copper pillar pads (12) include a pillar portion (121) and a pad portion (122). The pillar portion (121) passes through the dielectric layer (11). The pad portion (122) is connected to both ends of the pillar portion (121) and is located above and below the dielectric layer (11). The plurality of copper pillar pads (12) are spaced apart from each other. ABF film (13) is attached to the top of the prepared double-sided panel (10). A first blind hole (14) is drilled in the portion of the ABF film (13) corresponding to the column portion (121), and a conductive copper layer (15) is flash-plated on the upper side of the ABF film (13) and the portion corresponding to the sidewall of the first blind hole (14). Dry film (19) is applied to both the upper and lower surfaces of the double-sided panel (10) after the conductive copper layer (15) is flash-plated, and the dry film (19) on the upper surface of the double-sided panel (10) is partially exposed and removed corresponding to the first blind hole (14) to form the second blind hole (16). Copper / tin pillars (17) are plated in the second blind hole (16), and the dry film (19) on the upper and lower surfaces is removed, and the conductive copper layer (15) on the upper side of the ABF film (13) is removed to obtain the lower plate (18). A first prepreg (20) is attached to the underside of the lower plate (18), and a third blind hole (21) is drilled in the part of the first prepreg (20) corresponding to the column part (121) to obtain the middle plate (22). A second prepreg (30) is attached to the bottom of the prepared double-sided panel (10), and a fourth blind hole (31) is drilled in the part of the second prepreg (30) corresponding to the column part (121) to obtain the upper plate (32). Any at least two of the upper layer plate (32), the middle layer plate (22) and the lower layer plate (18) are stacked and pressed together in the vertical direction.

2. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The step of stacking and pressing together any two of the upper plate (32), the middle plate (22) and the lower plate (18) in the vertical direction includes: The upper plate (32), the middle plate (22) and the lower plate (18) are stacked and pressed together in the vertical direction, wherein the copper / tin pillar (17) of the middle plate (22) corresponds to the fourth blind hole (31) and the copper / tin pillar (17) of the lower plate (18) corresponds to the third blind hole (21).

3. The method for manufacturing a printed circuit board according to claim 2, characterized in that, The step of stacking and pressing the upper plate (32), the middle plate (22), and the lower plate (18) in the vertical direction, wherein the copper / tin pillars (17) of the middle plate (22) correspond to the fourth blind hole (31), and the copper / tin pillars (17) of the lower plate (18) correspond to the third blind hole (21) includes: There are multiple middle layer boards (22), which are stacked in the vertical direction. The copper / tin pillar (17) of one of two adjacent middle layer boards (22) corresponds to the third blind hole (21) of the other. The copper / tin pillar (17) of the uppermost middle layer board (22) corresponds to the fourth blind hole (31). The third blind hole (21) of the lowermost middle layer board (22) corresponds to the copper / tin pillar (17) of the lower layer board (18).

4. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The step of plating copper / tin pillars (17) in the third blind hole (21), removing the dry film (19) on the upper and lower surfaces, and removing the conductive copper layer (15) on the upper side of the ABF film (13) to obtain the lower board (18) further includes: Make the copper / tin pillar (17) protrude from the upper side of the ABF film (13), and set the length of the upper part of the copper / tin pillar (17) protruding from the upper side of the ABF film (13) in the vertical direction as L1, and L1 satisfies the relationship: 20μm≤L1≤40μm.

5. The method for manufacturing a printed circuit board according to claim 4, characterized in that, The copper / tin pillar (17) includes a copper pillar and a tin pillar, the tin pillar being located above the copper pillar, and the thickness of the tin pillar being less than the thickness of the copper pillar.

6. The method for manufacturing a printed circuit board (100) according to claim 1, characterized in that, The step of attaching the ABF film (13) to the prepared double-sided panel (10) includes: The ABF film (13) covers the top of the dielectric layer (11) and the pad portion (122) located on the dielectric layer (11).

7. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The step of drilling a first blind hole (14) in the portion of the ABF film (13) corresponding to the column portion (121), and flash-plating a conductive copper layer (15) on the upper side of the ABF film (13) and the portion corresponding to the sidewall of the first blind hole (14) includes: The thickness of the conductive copper layer (15) is set to L2, and L2 satisfies the relationship: 1μm≤L2≤2μm.

8. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The step of attaching dry film (19) to both the upper and lower surfaces of the double-sided panel (10) after flash plating the conductive copper layer (15), and partially exposing and removing the dry film (19) on the upper surface of the double-sided panel (10) corresponding to the first blind hole (14) to form the second blind hole (16) includes: The dry film (19) on the upper surface of the double-sided panel (10) is partially exposed and removed to form a first through hole corresponding to the first blind hole (14). The first through hole is connected to the first blind hole (14) to form a second blind hole (16). The width of the first through hole is greater than the width of the first blind hole (14).

9. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The distance between two adjacent copper pillar pads (12) in the double-sided panel (10) is set to L3, and L3 satisfies the relationship: 0.08mm≤L3≤0.12mm.

10. A printed circuit board (100), characterized in that, The method of manufacturing a printed circuit board applicable to any one of claims 1-9.

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