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: preparing a core board which comprises an insulating layer, an upper copper layer and a lower copper layer; a groove corresponding to the preset circuit pattern area is cut in the upper surface of the core board; the groove is subjected to roughening treatment; dry films are attached to the upper surface and the lower surface of the core plate, and groove areas are exposed; filling an electroplating copper layer in the groove; removing the dry film; and removing the part, which is not corresponding to the groove, of the upper copper layer in the vertical direction. Therefore, the groove corresponding to the preset circuit pattern area is cut in the upper surface of the core board, the depth of the groove penetrates into the insulating layer from the upper copper layer, then the groove is coarsened, and the copper layer is electroplated in the groove, so that the circuit embedded into the insulating layer can be formed on the upper surface of the core board; the bonding force between the insulating layer and the circuit is increased, the circuit is prevented from loosening, falling off or floating, and the stability and durability of the printed circuit board are 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] With the continuous development of semiconductor technology, the packaging process of circuit boards is also constantly improving, and the requirements for the stability and durability of circuit boards are becoming increasingly stringent. The bonding force between the circuit and the insulating dielectric layer is one of the key performance indicators for measuring the reliability and durability of circuit boards.

[0003] In related technologies, the bonding force between the circuit and the insulating dielectric layer is poor, and the circuit is prone to floating away from the insulating dielectric layer, which leads to poor stability and durability of the printed circuit board, requiring frequent repair or replacement of the circuit board. 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 (PCB) that is more reliable, improves the bonding force between the core board and the circuitry, prevents the circuitry from loosening, falling off, or detaching, and enhances the stability and durability of the PCB.

[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 core board, wherein the core board includes an insulating layer, an upper copper layer, and a lower copper layer, the upper copper layer and the lower copper layer being located on the upper surface and lower surface of the insulating layer, respectively; cutting a groove corresponding to a preset circuit pattern area on the upper surface of the core board, wherein the depth of the groove extends from the upper copper layer into the insulating layer; roughening the groove by horizontal descaling; attaching a dry film to the upper and lower surfaces of the core board, and exposing and developing the dry film on the upper surface of the core board to expose the groove; filling the groove with an electroplated copper layer, wherein the electroplated copper layer fills the groove, and the upper surface of the electroplated copper layer is flush with the upper surface of the dry film; removing the dry film on the upper and lower surfaces of the core board; removing the portion of the upper copper layer that does not correspond to the groove in the vertical direction, and retaining the portion of the upper copper layer that corresponds to the groove in the vertical direction and the electroplated copper layer.

[0007] Therefore, by cutting grooves corresponding to the preset circuit pattern area on the upper surface of the core board, and making the grooves penetrate from the upper copper layer to the insulating layer, and then roughening the grooves, and then electroplating copper layers in the grooves, circuits embedded in the insulating layer can be formed on the upper surface of the core board. This increases the bonding force between the insulating layer and the circuits, prevents the circuits from loosening, falling off or floating, and improves the stability and durability of the printed circuit board.

[0008] In some examples of the present invention, before the step of cutting a groove corresponding to the circuit pattern area on the upper surface of the core board, the method further includes: opening positioning holes for cutting alignment on the core board, wherein the positioning holes are provided adjacent to the corner areas of the core board, and there are multiple positioning holes, each of which corresponds to a multiple corner areas of the core board.

[0009] In some examples of the present invention, the step of roughening the groove by horizontal descaling further includes: simultaneously cleaning away the residue generated from cutting the groove by horizontal descaling.

[0010] In some examples of the present invention, the depth of the groove in the vertical direction is set to H, and the thickness of the core plate in the vertical direction is set to D. If D satisfies the relationship: 15%D≤15μm, then H satisfies the relationship: H=15%D.

[0011] In some examples of the present invention, the depth of the groove in the vertical direction is set to H, and the thickness of the core plate in the vertical direction is set to D. If D satisfies the relationship: 15%D>15μm, then H satisfies the relationship: H=15μm.

[0012] In some examples of the present invention, the grooves are irregularly distributed.

[0013] In some examples of the present invention, there are multiple grooves, which are spaced apart in a first direction. The width of the groove in the first direction is set as L1, and L1 satisfies the relationship: 13μm≤L1≤17μm.

[0014] In some examples of the present invention, the step of attaching a dry film to the upper and lower surfaces of the core board and exposing and developing the dry film on the upper surface of the core board to expose the groove further includes: the dry film having an exposure opening corresponding to the groove, and the width of the exposure opening in a first direction being greater than the width of the preset circuit pattern area in a first direction.

[0015] In some examples of the present invention, the thickness of the upper copper layer is set to L, and the difference between the width of the exposed opening and the width of the preset circuit pattern area in the first direction is set to X. Then L and X satisfy the relationship: 0≤X≤2L.

[0016] A printed circuit board according to an embodiment of the present invention includes: a manufacturing method for a printed circuit board as described above.

[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 flowchart of a method for manufacturing a printed circuit board according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the printed circuit board manufacturing process according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the printed circuit board manufacturing process according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the printed circuit board manufacturing process according to an embodiment of the present invention; Figure 6 This is a cross-sectional view during the fabrication process of a printed circuit board according to an embodiment of the present invention; Figure 7 This is a cross-sectional view during the fabrication process of a printed circuit board according to an embodiment of the present invention; Figure 8 This is a cross-sectional view during the fabrication process of a printed circuit board according to an embodiment of the present invention; Figure 9 This is a cross-sectional view during the fabrication process of a printed circuit board according to an embodiment of the present invention; Figure 10 This is a cross-sectional view during the fabrication process of a printed circuit board according to an embodiment of the present invention; Figure 11 This is a cross-sectional view during the fabrication process of a printed circuit board according to an embodiment of the present invention; Figure 12 This is a cross-sectional view of a printed circuit board after it has been manufactured according to an embodiment of the present invention.

[0019] Figure label: 100. Printed circuit boards; 10. Core board; 101. Insulation layer; 102. Upper copper layer; 103. Lower copper layer; 104. Positioning hole; 20. Groove; 30. Dry film; 301. Exposure port; 40. Copper layer; 50. Circuit; 501. Circuit diagram. 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 1-12 A method for manufacturing a printed circuit board 100 according to an embodiment of the present invention is described. The method for manufacturing the printed circuit board 100 can be used to produce the printed circuit board 100.

[0022] Combination Figures 1-12 As shown, the manufacturing method of the printed circuit board 100 according to the present invention mainly includes the following steps: preparing a core board 10, wherein the core board 10 includes an insulating layer 101, an upper copper layer 102 and a lower copper layer 103, the upper copper layer 102 and the lower copper layer 103 being located on the upper surface and lower surface of the insulating layer 101, respectively; cutting a groove 20 corresponding to the area of ​​a preset circuit pattern 501 on the upper surface of the core board 10, wherein the depth of the groove 20 extends from the upper copper layer 102 into the insulating layer 101; roughening the groove 20 by horizontal descaling; and cutting grooves 20 on the upper surface of the core board 10. A dry film 30 is applied to the upper and lower surfaces of the core board 10, and the dry film 30 on the upper surface of the core board 10 is exposed and developed to reveal the groove 20. An electroplated copper layer 40 is filled into the groove 20, wherein the electroplated copper layer 40 fills the groove 20 completely, and the upper surface of the electroplated copper layer 40 is flush with the upper surface of the dry film 30. The dry film 30 on the upper and lower surfaces of the core board 10 is removed. The portion of the upper copper layer 102 that does not correspond to the groove 20 in the vertical direction is removed, while the portion of the upper copper layer 102 that corresponds to the groove 20 in the vertical direction and the electroplated copper layer 40 are retained.

[0023] Specifically, a core board 10 is first prepared, which includes an insulating layer 101, an upper copper layer 102, and a lower copper layer 103. The upper copper layer 102 and the lower copper layer 103 are respectively tightly attached to the upper and lower surfaces of the insulating layer 101 to form a composite structure of a conductive layer and an insulating layer 101. The insulating layer 101 can effectively block electrical interference between the upper copper layer 102 and the lower copper layer 103. This not only ensures the electrical insulation performance and bidirectional conductivity of the core board 10, laying the foundation for the subsequent processing of the circuit 50, but also balances the internal stress of the core board 10 and prevents the core board 10 from warping and deforming during subsequent processing.

[0024] Furthermore, a groove 20 corresponding to the area of ​​the preset circuit pattern 501 is cut on the upper surface of the core board 10. The outline and position of the groove 20 are completely matched with the preset circuit pattern 501, which facilitates subsequent processing steps such as electroplating and etching of the circuit 50, ensures the manufacturing accuracy of the circuit 50, and prevents the circuit 50 from shifting.

[0025] Furthermore, the groove 20 extends from the upper copper layer 102 into the insulating layer 101. Compared to extending the groove 20 from the upper copper layer 102 to the upper surface of the insulating layer 101, extending the groove 20 from the upper copper layer 102 into the insulating layer 101 allows for the subsequent formation of lines 50 embedded in the insulating layer 101, thereby improving the bonding strength between the lines 50 and the insulating layer 101 and enhancing the stability and durability of the printed circuit board 100.

[0026] In some embodiments of the present invention, a groove 20 corresponding to the area of ​​a preset circuit pattern 501 is cut on the upper surface of the core board 10 using ultraviolet laser cutting technology. The ultraviolet laser cutting machine is equipped with editing software corresponding to the processing path. The file of the corresponding preset circuit pattern 501 is uploaded to the editing software, and the reference coordinates are set. The preset circuit pattern 501 can then be converted into the processing path of the ultraviolet laser cutting machine through the editing software, thus making the processing path of the ultraviolet laser cutting machine the same as the preset circuit pattern 501. The cutting width of the ultraviolet laser cutting process is adjustable, preferably 15μm, to meet the specifications of a line width of 20μm to 30μm and a line spacing of 20μm to 30μm. When the line width and line spacing on the printed circuit board 100 are other values, other processes such as mechanical sawing, die punching, or milling can be used instead.

[0027] Furthermore, the inner wall of the groove 20 is roughened by horizontal descaling. The inner wall of the groove 20 includes the cut surface of the upper copper layer 102 and the exposed surface of the insulating layer 101. This increases the roughness of the inner wall of the groove 20, increases the contact area and bonding force between the inner wall surface of the groove 20 and the plating layer, and prevents the plating layer from peeling off or loosening.

[0028] Furthermore, a dry film 30 is attached to the upper surface of the upper copper layer 102 and the lower surface of the lower copper layer 103, and the preset circuit pattern 501 is aligned with the dry film 30. Then, the dry film 30 on the upper side of the upper copper layer 102 is exposed and developed to reveal the groove 20. This not only facilitates the subsequent electroplating process in the groove 20 to form a plating layer corresponding to the circuit pattern 501, but also ensures that the position and size of the circuit 50 meet the design requirements through the circuit pattern 501 formed on the surface of the dry film 30.

[0029] Furthermore, an electroplated copper layer 40 is filled into the groove 20 to form a plating layer corresponding to the circuit pattern 501. The electroplated copper layer 40 fills the groove 20 completely, and the upper surface of the electroplated copper layer 40 is flush with the upper surface of the dry film 30. This not only improves the perpendicularity of the circuit 50 relative to the core board 10 and the accuracy of the height of the circuit 50, and avoids the upper surface of the circuit 50 from protruding or sinking relative to the upper surface of the dry film 30, thus affecting the manufacturing accuracy of the circuit 50, but also improves the flatness of the upper surface of the copper layer 40 and improves the overall flatness of the printed circuit board 100.

[0030] Thus, the height of the dry film 30 determines the height of the circuit 50. Increasing the height of the dry film 30 increases the height of the circuit 50, thereby improving its current-carrying capacity. The height of the dry film 30 should be set according to the preset height of the circuit 50 and the processing technology. The height of the circuit 50 refers to its vertical dimension.

[0031] In some other embodiments of the present invention, the upper surface of the electroplated copper layer 40 is not flush with the upper surface of the dry film 30, wherein the height of the electroplated copper layer 40 is set according to the preset height of the circuit 50 and the processing technology, etc.

[0032] Furthermore, the dry film 30 on the upper and lower surfaces of the core board 10 is removed, which makes it easier to remove the excess upper copper layer 102.

[0033] Furthermore, the portions of the upper copper layer 102 that do not correspond to the groove 20 in the vertical direction are removed, while the portions of the upper copper layer 102 that correspond to the groove 20 in the vertical direction and the electroplated copper layer 40 are retained, thereby completing the fabrication of the circuit 50 on the upper surface of the core board 10. The upper copper layer 102 electrically connects different circuits 50. Removing the upper copper layer 102 in areas other than circuit 50 electrically isolates different circuits 50, ensuring the normal function of the circuits 50 and the normal operation of the printed circuit board 100.

[0034] Therefore, a groove 20 corresponding to the area of ​​the preset circuit pattern 501 is first cut on the upper surface of the core board 10, and the depth of the groove 20 extends from the upper copper layer 102 into the insulating layer 101. Then, the groove 20 is roughened, and a copper layer 40 is electroplated in the groove 20. Finally, a circuit 50 is formed on the upper surface of the core board 10. This forms a circuit 50 embedded in the insulating layer 101, increases the bonding force between the insulating layer 101 and the circuit 50, and prevents the circuit 50 from loosening, falling off, or floating away. This improves the stability and durability of the printed circuit board 100, extends the service life of the printed circuit board 100, and reduces the maintenance and replacement frequency of the printed circuit board 100.

[0035] In some embodiments of the present invention, the lower copper layer 103 side of the core board 10 may adopt the same processing steps and processes as the upper copper layer 102 side.

[0036] In some embodiments of the present invention, the structures forming lines 50 on the upper surface and / or lower surface of the core board 10 can be stacked in the vertical direction to form a multilayer printed circuit board 100. Holes can be drilled in the core board 10 and penetrate it, thereby enabling conduction between different layers of lines 50 through the dielectric material within the holes.

[0037] Combination Figure 3 , Figure 4 and Figure 5 As shown, before the step of cutting a groove 20 corresponding to the area of ​​the circuit pattern 501 on the upper surface of the core board 10, the method further includes: opening positioning holes 104 for cutting alignment on the core board 10, wherein the positioning holes 104 are set near the corner area of ​​the core board 10, and there are multiple positioning holes 104, which correspond one-to-one with multiple corner areas of the core board 10.

[0038] Specifically, a positioning hole 104 is made through the core board 10. Before processing the core board 10, the core board 10 needs to be fixed through the positioning hole 104. This not only ensures the stability of the printed circuit board 100 during the processing and improves the accuracy of the setting position of the line 50, but also makes it easier to set the line pattern 501 on the core board 10 with the positioning hole 104 as a reference.

[0039] In addition, the positioning hole 104 can also facilitate the assembly of the printed circuit board 100, and improve the assembly accuracy and efficiency of the printed circuit board 100 in the corresponding equipment.

[0040] Furthermore, the positioning hole 104 is located near the corner area of ​​the core board 10. This not only helps to limit the translation and rotation of the printed circuit board 100 to the greatest extent, but also keeps the positioning hole 104 away from the core functional area of ​​the printed circuit board 100. When fixing the printed circuit board 100, it can prevent the force of the tooling fixture from damaging the lines 50, components and other key structures on the printed circuit board 100.

[0041] Furthermore, there are multiple positioning holes 104, each corresponding to a different corner region of the core board 10. This not only improves the stability of the printed circuit board 100 during processing through the cooperation of multiple positioning holes 104, but also prevents the stability of the printed circuit board 100 during processing from being affected by the structural failure of a single positioning hole 104. The number of positioning holes 104 can be two or more.

[0042] Combination Figure 5 , Figure 6 and Figure 7 As shown, the step of roughening the groove 20 by horizontal descaling also includes: simultaneously cleaning away the residue generated from cutting the groove 20 by horizontal descaling.

[0043] Specifically, the residue generated during the cutting of the groove 20 will adhere to the inner wall of the groove 20. If it is not removed, it will hinder the direct contact between the subsequent electroplated copper layer 40 and the inner wall of the groove 20, resulting in insufficient bonding force between the electroplated copper layer 40 and the core board 10. The cleaned inner wall can form a tight bond with the electroplated copper layer 40, improving the structural stability of the circuit 50.

[0044] Combination Figure 5 , Figure 6 and Figure 7 As shown, the depth of the groove 20 in the vertical direction is set to H, and the thickness of the core plate 10 in the vertical direction is set to D. If D satisfies the relationship: 15%D≤15μm, then H satisfies the relationship: H=15%D.

[0045] This design, when the core board 10 is relatively thin, not only prevents the groove 20 from being too deep and damaging the structure of the core board 10, but also preserves a sufficiently thick insulation layer 101 to prevent the groove 20 on the upper surface of the core board 10 from penetrating the core board 10 and damaging the lower copper layer 103 or the circuit 50 on the lower surface of the core board 10. It also prevents the groove 20 from being too shallow, resulting in poor bonding between the core board 10 and the circuit 50. Furthermore, this design ensures both the structural stability and reliability of the core board 10, while also ensuring good bonding between the core board 10 and the circuit 50, preventing the circuit 50 from loosening, falling off, or detaching.

[0046] Combination Figure 5 , Figure 6 and Figure 7 As shown, the depth of the groove 20 in the vertical direction is set to H, and the thickness of the core plate 10 in the vertical direction is set to D. If D satisfies the relationship: 15%D>15μm, then H satisfies the relationship: H=15μm.

[0047] With this setup, when the core board 10 is thick, a groove 20 of a certain depth is provided to ensure good bonding between the core board 10 and the circuit 50. There is no need to provide an excessively deep groove 20. This reduces the processing difficulty of the groove 20 and prevents the core board 10 from cracking or the circuit 50 from having excessive resistance due to an excessively deep groove 20.

[0048] In some embodiments of the present invention, the reference value for setting the depth of the groove 20 in the vertical direction includes, but is not limited to, 15 μm. The depth of the groove 20 in the vertical direction can be adjusted according to the thickness of the core board 10, the material of the core board 10, the processing technology and the specific application environment.

[0049] Combination Figure 6 , Figure 7and Figure 12 As shown, the grooves 20 are irregularly distributed. Specifically, after the grooves 20 are roughened, uniformly distributed pits, micropores, or microcracks are formed on the inner wall of the grooves 20, making the overall shape of the grooves 20 irregular. Among them, the overall shape of the grooves 20 can be honeycomb-like, tree root-like, or multi-segment zigzag-like, which can effectively improve the bonding force between the circuit 50 and the core board 10, prevent the circuit 50 from loosening, falling off, or floating away, and improve the stability and durability of the printed circuit board 100.

[0050] In some embodiments of the present invention, before the groove 20 is roughened, the cross-sectional shape of the groove 20 in the vertical direction includes, but is not limited to, a portion of a triangle, trapezoid, rectangle, or circle.

[0051] Combination Figure 5 , Figure 6 and Figure 7 As shown, there are multiple grooves 20, which are spaced apart in the first direction. The width of the groove 20 in the first direction is set as L1, and L1 satisfies the relationship: 13μm≤L1≤17μm.

[0052] Specifically, setting multiple grooves 20 can facilitate the formation of multiple stable lines 50. The multiple grooves 20 are spaced apart in the first direction, which can prevent structural interference between adjacent grooves 20 and prevent electrical contact between adjacent lines 50 that is not designed for the lines 50. Setting the width range of the grooves 20 in the first direction can not only facilitate the processing and formation of the lines 50 and prevent deviation of the line pattern 501, thus improving the manufacturing accuracy of the lines 50, but also improve the stability of the core board 10 and prevent the core board 10 from breaking or deforming.

[0053] The width of the line 50 in the first direction can be slightly larger than the width of the groove 20 in the first direction to further improve the stability and reliability of the line 50. The specific width value of the groove 20 in the first direction should be set according to the specific width of the line 50, the spacing between different lines 50, the processing technology, and processing losses.

[0054] In some embodiments of the present invention, when the cutting width of the ultraviolet laser cutting process is set to 15μm, the specifications of line width of 20μm to 30μm and line spacing of 20μm to 30μm can be met. Furthermore, by setting the width of the groove 20 in the first direction within the above-mentioned range, the width of the groove 20 in the first direction can be made smaller than the width of the line 50, thereby improving the stability and durability of the line 50.

[0055] Combination Figures 8-12As shown, the process of applying a dry film 30 to the upper and lower surfaces of the core board 10 and exposing and developing the dry film 30 on the upper surface of the core board 10 to expose the groove 20 further includes: the dry film 30 having an exposure opening 301, the exposure opening 301 corresponding to the groove 20, and the width of the exposure opening 301 in the first direction being greater than the width of the preset circuit pattern 501 area in the first direction.

[0056] Specifically, the exposed opening 301 will be filled with the electroplated copper layer 40. The width of the exposed opening 301 in the first direction is the width of the electroplated copper layer 40 in the first direction. During the removal of the upper copper layer 102, a portion of both sides of the electroplated copper layer 40 in the first direction will also be removed. In other words, the width of the final formed circuit 50 in the first direction will be smaller than the width of the electroplated copper layer 40 in the first direction. Therefore, the width of the exposed opening 301 in the first direction should be greater than the width of the preset circuit pattern 501 area in the first direction to compensate for the reduction in width of the electroplated copper layer 40 in the first direction due to the removal of the upper copper layer 102.

[0057] Combination Figures 8-12 As shown, the thickness of the upper copper layer 102 is set to L, and the difference between the width of the exposed opening 301 and the width of the preset circuit pattern 501 area in the first direction is set to X. Then L and X satisfy the relationship: 0≤X≤2L.

[0058] Specifically, the width of the exposure opening 301 in the first direction is the width of the electroplated copper layer 40 in the first direction. After the dry film 30 is removed, when the upper copper layer 102 is removed by etching, the thickness of the upper copper layer 102 will be etched away on both sides of the electroplated copper layer 40 in the first direction. In other words, the width of the electroplated copper layer 40 in the first direction should be twice the width of the upper copper layer 102 in the first direction of the preset circuit pattern 501 area. That is, the width of the electroplated copper layer 40 in the first direction of the exposure opening 301 should be twice the width of the upper copper layer 102 in the first direction of the preset circuit pattern 501 area to compensate for the reduction in width of the electroplated copper layer 40 in the first direction due to the etching process of the upper copper layer 102, so that the actual width of the finally formed circuit 50 is the same as the width in the first direction of the preset circuit pattern 501 area.

[0059] However, in the actual manufacturing of the printed circuit board 100, different manufacturing processes may be used, and the dimensions of the copper plating layer 40 etched away on both sides in the first direction may also differ. Consequently, the width deviation between the actual circuit 50 and the preset circuit pattern 501 will also differ, requiring different pre-compensation values ​​for the copper plating layer 40. That is, the difference between the width of the exposed opening 301 in the first direction and the width of the preset circuit pattern 501 area in the first direction will vary. Therefore, the difference between the width of the exposed opening 301 and the width of the preset circuit pattern 501 area in the first direction can be adjusted based on the specific manufacturing process of the printed circuit board 100, precision requirements, predictable system errors, and application environment.

[0060] According to the printed circuit board 100 of the present invention, the above-described manufacturing method of the printed circuit board 100 is applicable. Specifically, since the manufacturing method of the printed circuit board 100 is more reliable and the bonding effect between the circuit 50 and the insulating layer 101 is better, using the manufacturing method of the printed circuit board 100 to manufacture the printed circuit board 100 can prevent the circuit 50 in the printed circuit board 100 from becoming loose, falling off, or floating away, thereby improving the stability and reliability of the printed circuit board 100 and extending its service life.

[0061] 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.

[0062] 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.

[0063] 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 core board (10) is prepared, wherein the core board (10) includes an insulating layer (101), an upper copper layer (102) and a lower copper layer (103), wherein the upper copper layer (102) and the lower copper layer (103) are located on the upper surface and the lower surface of the insulating layer (101), respectively. A groove (20) corresponding to the area of ​​the preset circuit pattern (501) is cut out on the upper surface of the core board (10), wherein the depth of the groove (20) extends from the upper copper layer (102) to the insulating layer (101); The groove (20) is roughened by horizontal descaling; Dry film (30) is attached to the upper and lower surfaces of the core plate (10), and the dry film (30) on the upper surface of the core plate (10) is exposed and developed to expose the groove (20); An electroplated copper layer (40) is filled in the groove (20), wherein the electroplated copper layer (40) fills the groove (20) completely, and the upper surface of the electroplated copper layer (40) is flush with the upper surface of the dry film (30). Remove the dry film (30) from the upper and lower surfaces of the core plate (10); Remove the portion of the upper copper layer (102) that does not correspond to the groove (20) in the vertical direction, and retain the portion of the upper copper layer (102) that corresponds to the groove (20) in the vertical direction and the electroplated copper layer (40).

2. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The step of cutting a groove (20) corresponding to the area of ​​the circuit pattern (501) on the upper surface of the core board (10) further includes: Positioning holes (104) for cutting alignment are opened on the core plate (10), wherein the positioning holes (104) are arranged near the corner area of ​​the core plate (10), and there are multiple positioning holes (104), each of which corresponds to a multiple corner area of ​​the core plate (10).

3. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The step of roughening the groove (20) by horizontal deburring further includes: At the same time, the residue generated by the cutting groove (20) is cleaned away by horizontal descaling.

4. The method for manufacturing a printed circuit board according to claim 1, characterized in that, Let the depth of the groove (20) in the vertical direction be H, and let the thickness of the core plate (10) in the vertical direction be D. If D satisfies the relationship: 15%D≤15μm, then H satisfies the relationship: H=15%D.

5. The method for manufacturing a printed circuit board according to claim 1, characterized in that, Let the depth of the groove (20) in the vertical direction be H, and let the thickness of the core plate (10) in the vertical direction be D. If D satisfies the relationship: 15%D>15μm, then H satisfies the relationship: H=15μm.

6. The method for manufacturing a printed circuit board according to claim 1, characterized in that, The grooves (20) are irregularly distributed.

7. The method for manufacturing a printed circuit board according to claim 1, characterized in that, There are multiple grooves (20), and the multiple grooves (20) are spaced apart in the first direction. The width of the groove (20) in the first direction is set as L1, and L1 satisfies the relationship: 13μm≤L1≤17μm.

8. The method for manufacturing a printed circuit board according to claim 7, characterized in that, The step of attaching a dry film (30) to the upper and lower surfaces of the core plate (10) and exposing and developing the dry film (30) on the upper surface of the core plate (10) to expose the groove (20) further includes: The dry film (30) has an opening (301) that corresponds to the groove (20). The width of the opening (301) in the first direction is greater than the width of the area of ​​the preset circuit pattern (501) in the first direction.

9. The method for manufacturing a printed circuit board according to claim 8, characterized in that, The thickness of the upper copper layer (102) is set to L, and the difference between the width of the exposed opening (301) and the width of the preset circuit pattern (501) area in the first direction is set to X. Then L and X satisfy the relationship: 0≤X≤2L.

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

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