Printed circuit board and manufacturing method thereof

Abstract

The invention discloses a printed circuit board and a manufacturing method of the printed circuit board. The printed circuit board is characterized in that metal wires are arranged inside and / or on the surface of the printed circuit board; the cross section of the metal wire in the axial direction is in a polygon shape, and the number of edges of the polygon is larger than four. Wherein the metal wires are symmetric about a first symmetric axis and a second symmetric axis; the first symmetric axis is an axis which passes through the center of the cross section and is vertical to the surface of the printed circuit board, and the second symmetric axis is an axis which passes through the center of the cross section and is parallel to the surface of the printed circuit board. Through the above mode, insertion loss can be effectively reduced, transmission efficiency and signal integrity can be improved, a simple structure can be maintained, and production requirements can be met.

Description

Technical Field

[0001] The present application relates to the field of printed circuit boards, and particularly to a printed circuit board and a manufacturing method thereof. Background Art

[0002] With the rapid development of industries such as communication technology, artificial intelligence, and big data, the requirements for the manufacturing process technology of printed circuit boards are also constantly increasing, becoming the pursuit of the industry. Especially for insertion loss, as an important production index of circuit boards, stricter control is required. Insertion loss has a significant impact on the reliability and stability of products. Existing printed circuit boards are difficult to meet the growing product requirements and still need to be improved. Summary of the Invention

[0003] To solve the above technical problems, the present application provides a printed circuit board and a manufacturing method thereof, which can effectively reduce insertion loss, improve transmission efficiency and signal integrity, maintain a simple structure, and meet production requirements.

[0004] To solve the above technical problems, the technical solution adopted by the present application first provides a printed circuit board.

[0005] The printed circuit board includes: metal wires are arranged on the inside and / or surface of the printed circuit board; the cross-sectional shape of the metal wire along the axial direction is a polygon, and the number of sides of the polygon is greater than four; wherein, the metal wire is axisymmetric about a first axis of symmetry and a second axis of symmetry; the first axis of symmetry is an axis passing through the center of the cross-section and perpendicular to the surface of the printed circuit board, and the second axis of symmetry is an axis passing through the center of the cross-section and parallel to the surface of the printed circuit board.

[0006] Wherein, the cross-sectional shape of the metal wire is an octagon.

[0007] To solve the above technical problems, the second aspect of the present application provides a manufacturing method of a printed circuit board, wherein the manufacturing method of the printed circuit board is used to prepare any one of the above printed circuit boards.

[0008] The manufacturing method includes: preparing a metal sheet, making a groove on one side surface of the metal sheet so that a metal block with the surface shape of a metal wire is formed on the surface of the metal sheet; wherein, the groove forming the metal block is axisymmetric about a first symmetry axis, the metal block is axisymmetric about the first symmetry axis, and the first symmetry axis is an axis passing through the center of the cross-section and perpendicular to the surface of the metal sheet; placing the surfaces of two metal sheets with grooves opposite to each other, and pressing them with an insulating material so that the insulating material fills the grooves; making the same grooves on the surface of the metal sheet opposite to the side where the insulating material is pressed, so that metal blocks with the surface shape of metal wires are formed on both surfaces of the metal sheet; wherein, the grooves on both surfaces of the metal sheet are axisymmetric about a second symmetry axis, and the formed metal blocks are axisymmetric about the second symmetry axis, and the second symmetry axis is an axis passing through the center of the cross-section and parallel to the surface of the metal sheet; developing and etching the metal sheet to expose the insulating material, forming a substrate body with metal wires, wherein the cross-sectional shape of the metal wires in the axial direction is a polygon, and the number of sides of the polygon is greater than four.

[0009] Wherein, the manufacturing method includes: the groove is an inclined groove, the side wall of the inclined groove is perpendicular to the surface of the metal sheet, and the ratio range of the depth to the width of the inclined groove is 1:1 to 1:1.5.

[0010] Wherein, the manufacturing method includes: the depth of the grooves on both surfaces of the metal sheet is 10% - 20% of the thickness of the metal wire.

[0011] Wherein, the manufacturing method includes: the groove is formed by laser ablation, and the ablation degree of the laser is controlled to form an inclined surface with a slope on the inclined groove, and the inclined surface of the inclined groove includes one and / or more slopes.

[0012] Wherein, the step of making the same grooves on the surface of the metal sheet opposite to the side where the insulating material is pressed so that metal blocks with the surface shape of metal wires are formed on both surfaces of the metal sheet includes: plating tin on the surface of the metal sheet opposite to the side where the insulating material is pressed, ablating the tin layer by laser in the projection area where the groove is set to expose the surface of the metal sheet; removing the tin layer after making the same grooves on the surface.

[0013] Wherein, the step of developing and etching the metal sheet to expose the insulating material and forming a substrate body with metal wires includes: pressing insulating materials on both surfaces of the substrate body to make an insulating encapsulation layer; making a surface metal layer on the surface of the insulating encapsulation layer to form a printed circuit board.

[0014] Wherein, the step of encapsulating the surface of the substrate body by pressing an insulating material includes: pressing the substrate body with an insulating material on the surface of the substrate body to form multiple layers of metal wires.

[0015] Among them, the steps of fabricating a surface metal layer on the surface of the insulation encapsulation layer to enable the internal setting of metal wires in the printed circuit board include: fabricating a groove on the surface of the metal sheet; pressing the surface with the groove to the surface of the insulation encapsulation layer away from the substrate body to form the surface metal layer; fabricating a groove on the surface of the surface metal layer to enable the setting of metal wires on the surface of the printed circuit board.

[0016] Different from the prior art, the printed circuit board and the manufacturing method thereof provided in this application can effectively reduce the insertion loss, improve the transmission efficiency and signal integrity, maintain a simple structure, reduce the production cost, and meet the production requirements. Description of the Drawings

[0017] Figure 1 is a schematic structural diagram of an embodiment of the printed circuit board of this application;

[0018] Figure 2 is a schematic structural diagram of another embodiment of the printed circuit board of this application;

[0019] Figure 3 is a schematic diagram of the signal simulation results of the metal wires of another embodiment of the printed circuit board of this application and the existing straight lines;

[0020] Figure 4 is a schematic flow diagram of the processing steps of an embodiment of the manufacturing method of the printed circuit board of this application;

[0021] Figures 5a to 5g is a set of schematic structural diagrams of the processing steps of an embodiment of the manufacturing method of the printed circuit board of this application;

[0022] Figure 6 is a schematic flow diagram of the processing steps of another embodiment of the manufacturing method of the printed circuit board of this application;

[0023] Figures 7a to 7j is a set of schematic structural diagrams of the processing steps of another embodiment of the manufacturing method of the printed circuit board of this application;

[0024] Figure 8 is a schematic flow diagram of the processing steps of yet another embodiment of the manufacturing method of the printed circuit board of this application;

[0025] Figures 9a to 9c is a set of schematic structural diagrams of the processing steps of yet another embodiment of the manufacturing method of the printed circuit board of this application. Detailed Embodiments

[0026] The present application will be described in detail below with reference to the drawings and embodiments.

[0027] The present application first provides a printed circuit board. Please refer to Figure 1 , Figure 1It is a schematic structural diagram of an embodiment of the printed circuit board of the present application.

[0028] As Figure 1 shown, the printed circuit board 100 in this embodiment includes:

[0029] The printed circuit board 100 includes: Metal wires 101 are provided on the inside and / or surface of the printed circuit board 100; The cross-sectional shape of the metal wire 101 in the axial direction is a polygon, and the number of sides of the polygon is greater than four.

[0030] The outer shape of the metal wire 101 is an important influencing factor affecting the insertion loss of the metal wire 101. The material of the metal wire 101 can be a metal with good conductivity or low insertion loss, such as copper, copper alloy, aluminum, aluminum alloy, etc.

[0031] The printed circuit board 100 can be a multi-layer printed circuit board 100. Metal wires 101 are provided on one or more internal layers according to production requirements, or metal wires 101 are only provided on the metal layer on the surface of the printed circuit board 100, or metal wires 101 are provided on the entire board. According to the position of the provided metal wires 101, the product effect required by production is achieved.

[0032] The polygon can be a pentagon, hexagon, octagon, decagon, dodecagon, etc. Effectively increasing the number of sides of the outer shape of the metal wire 101 makes the metal wire 101 as round as possible, which can effectively reduce the insertion loss. However, the increase in the number of sides during the processing process also increases the processing steps and processing costs. Therefore, it is necessary to design the corresponding number of sides of the wire outer shape according to the specific requirements of the product.

[0033] In a specific embodiment, the metal wire 101 can be a structure with a cross-sectional shape of a polygon etched or laser processed on a copper foil or a copper substrate; The copper foil can be first processed into the required metal wire 101 structure and then laminated and encapsulated onto the printed circuit board 100, or the copper foil or copper substrate can be first laminated and encapsulated onto the printed circuit board 100, and then processed on the copper foil or copper substrate.

[0034] Among them, the metal wire 101 is axisymmetric about the first symmetry axis and the second symmetry axis; The first symmetry axis is an axis passing through the center of the cross-section and perpendicular to the surface of the printed circuit board 100, and the second symmetry axis is an axis passing through the center of the cross-section and parallel to the surface of the printed circuit board 100.

[0035] The metal wire 101 forming an axisymmetric figure can maintain the consistency and integrity during the signal transmission process, and can reduce the deformation caused by thermal expansion or mechanical stress during the processing and use processes, improving the reliability of the printed circuit board 100.

[0036] Please refer to Figure 2 , Figure 2It is a schematic structural diagram of another embodiment of the printed circuit board of the present application.

[0037] As Figure 2 shown, the printed circuit board 100 in this embodiment includes:

[0038] The printed circuit board 100 includes: metal wires 101 are disposed on the inside and / or surface of the printed circuit board 100; the cross-sectional shape of the metal wires 101 in the axial direction is a polygon, and the number of sides of the polygon is greater than four; the outer shape of the metal wires 101 is an important influencing factor affecting the insertion loss of the metal wires 101, and the material of the metal wires 101 can be a metal with good electrical conductivity or low insertion loss such as copper, copper alloy, aluminum, aluminum alloy, etc.

[0039] The printed circuit board 100 can be a multi-layer printed circuit board 100. Metal wires 101 are disposed on one or more internal layers according to production requirements, or metal wires 101 are only disposed on the metal layer on the surface of the printed circuit board 100, or metal wires 101 are disposed on the entire board. It can be understood that metal wires 101 can also be selected to be disposed on a part of the metal wires 101 in one layer, and the desired product effect can be achieved according to the position of the disposed metal wires 101.

[0040] The polygon can be a pentagon, hexagon, octagon, decagon, dodecagon, etc. Effectively increasing the number of sides of the outer shape of the metal wires 101 makes the metal wires 101 as round as possible, which can effectively reduce the insertion loss. However, the increase in the number of sides during the processing process also increases the processing steps and processing costs. Therefore, the corresponding number of sides of the wire outer shape needs to be designed according to the specific requirements of the product.

[0041] In a specific embodiment, the metal wires 101 can be structures with a cross-sectional shape of a polygon etched or laser processed on a copper foil or a copper substrate; the copper foil can be first processed into the required metal wire 101 structure and then laminated and encapsulated onto the printed circuit board 100, or the copper foil or copper substrate can be first laminated and encapsulated onto the printed circuit board 100, and then processed on the copper foil or copper substrate.

[0042] Among them, the metal wires 101 are axisymmetric about the first symmetry axis and the second symmetry axis; the first symmetry axis is an axis passing through the center of the cross-section and perpendicular to the surface of the printed circuit board 100, and the second symmetry axis is an axis passing through the center of the cross-section and parallel to the surface of the printed circuit board 100.

[0043] The metal wires 101 forming an axisymmetric figure can maintain the consistency and integrity during the signal transmission process, and can reduce the deformation caused by thermal expansion or mechanical stress during the processing and use processes, improving the reliability of the printed circuit board 100.

[0044] In an alternative embodiment, the cross-sectional shape of the metal wire 101 is octagonal.

[0045] When the cross-sectional shape of the metal wire 101 is octagonal, it can effectively reduce the insertion loss of the metal wire and take into account the tightness and bonding degree of the processing of the printed circuit board 100, so as to obtain a reliable printed circuit board 100 in processing.

[0046] In an alternative embodiment, the line width of the metal wire 101 is 4 mil to 12 mil, specifically it can be 4 mil, 5 mil, 6 mil, 8 mil, 10 mil, 12 mil, and the thickness is determined according to the thickness of the processed copper foil or copper substrate, with a range of 0.5 oz to 2 oz, specifically it can be 0.5 oz, 1 oz, 1.5 oz, 2 oz, etc., and it is specifically determined according to the requirements of current carrying and signal transmission.

[0047] In a specific embodiment, please refer to Figure 3 , Figure 3 which is a schematic diagram of the signal simulation results of the metal wire of another embodiment of the printed circuit board of the present application and the existing straight line;

[0048] In the simulation results, the line specifications of the metal wire of another embodiment of the printed circuit board of the present application and the existing straight line are both 100 mil in length, 6 mil in line width, and 8 mil in line spacing.

[0049] As Figure 3 shown, the Y-axis is the loss coefficient, the X-axis is the frequency, curve a is the signal simulation result of the straight line, and curve b is the signal simulation result of the metal wire of another embodiment of the printed circuit board of the present application. It can be obtained that from port 2 to port 1, the SDD (Differential Insertion Loss) of the metal wire of another embodiment of the printed circuit board of the present application has a significant reduction in insertion loss.

[0050] The present application also provides a method for manufacturing a printed circuit board, wherein the method for manufacturing a printed circuit board is used to prepare the printed circuit board as described above in any one.

[0051] Please refer to Figure 4 and Figures 5a to 5g , which is a schematic flow diagram of the processing steps of an embodiment of the method for manufacturing a printed circuit board of the present application; Figures 5a to 5g is a set of schematic structural diagrams of the processing steps of an embodiment of the method for manufacturing a printed circuit board of the present application.

[0052] The manufacturing method includes: S101: Prepare a metal sheet, and make a groove 103 on one surface of the metal sheet, so that a metal block with the surface shape of the metal wire 101 is formed on the surface of the metal sheet 102. Among them, the groove 103 for forming the metal block 104 is axisymmetric along the first symmetry axis, the metal block 104 is axisymmetric along the first symmetry axis, and the first symmetry axis is the axis passing through the center of the cross-section and perpendicular to the surface of the metal sheet 102;

[0053] The material of the metal sheet 102 can be a metal with good conductivity or low insertion loss such as copper, copper alloy, aluminum, aluminum alloy, etc. The thickness is determined according to the thickness of the processed copper foil or copper substrate, and the range is 0.5 oz to 2 oz. Specifically, it can be 0.5 oz, 1 oz, 1.5 oz, 2 oz, etc. Specifically, it is determined according to the demand for carrying current and the demand for signal transmission.

[0054] The groove 103 can be made by etching, laser ablation or machine tool etching. It can be understood that there is more than one metal wire 101 on the printed circuit board 100. In a specific implementation manner, after all the grooves 103 on one surface of the metal sheet 102 are made, the grooves 103 on the other surface are made.

[0055] As Figure 5a shown, in this embodiment, grooves 103 with different slopes are made on one surface of the metal sheet 102, so that the formed metal block 104 has a cross-sectional shape close to a roundness.

[0056] By making the groove 103, a metal block 104 axisymmetric along the first symmetry axis is formed on the metal sheet 102, so that the metal wire 101 formed after processing the metal block 104 is also a figure axisymmetric along the first symmetry axis, which can maintain the consistency and integrity during signal transmission, and can reduce the deformation caused by thermal expansion or mechanical stress during processing and use, and improve the reliability of the printed circuit board 100.

[0057] As Figure 5b shown, S102: Place the surfaces of two metal sheets 102 with grooves 103 facing each other, and press them with the insulating material 105 so that the insulating material 105 fills the grooves 103.

[0058] The two metal sheets 102 are fixed by the insulating material 105, so that there is support and fixation when processing the grooves 103 on the other side of the metal sheet 102, and an insulating layer (not marked in the figure) is provided between the two metal wires 101 formed subsequently, which can effectively save the process and reduce the processing cost.

[0059] S103: Make the same grooves 103 on the surface of the metal sheet 102 on the side opposite to the side where the insulating material 105 is laminated, so that metal blocks with the surface shape of the metal wire 101 are formed on both surfaces of the metal sheet 102. Among them, the grooves 103 on both surfaces of the metal sheet 102 are axisymmetric about the second axis of symmetry, and the formed metal blocks 104 are axisymmetric about the second axis of symmetry. The second axis of symmetry is the axis passing through the center of the cross-section and parallel to the surface of the metal sheet 102;

[0060] As Figure 5c shown, the metal blocks 104 formed on both surfaces of a metal sheet 102 are axisymmetric about the second axis of symmetry, which can make the metal wire 101 formed after processing the metal blocks 104 also axisymmetric about the second axis of symmetry.

[0061] S104: Develop and etch the metal sheet 102 to expose the insulating material, forming a substrate body with the metal wire 101. Among them, the cross-sectional shape of the metal wire 101 in the axial direction is a polygon, and the number of sides of the polygon is greater than four.

[0062] As Figure 5d shown, cover a wet film on the metal sheet 102, expose the wet film, cure the wet film in the projection area of the metal wire 101, and the wet film in the part that needs to be removed is not cured, and then perform etching to form, as Figure 5e shown, the metal wire 101 fixed on the insulating material 105, and perform a stripping treatment on the developing film covering the metal wire 101 to form, as Figure 5f shown, the substrate body 107 with the metal wire 101.

[0063] Then perform subsequent production operations on the substrate body 107, such as insulation encapsulation, metal plating, etching, etc., to form the final printed circuit board 100.

[0064] Among them, the polygonal interface shape of the metal wire 101 can be a pentagon, hexagon, octagon, decagon, dodecagon, etc. Effectively increasing the number of outer sides of the metal wire 101 makes the metal wire 101 as round as possible, which can effectively reduce the insertion loss. However, the increase in the number of sides during the processing process also increases the processing steps and processing costs accordingly. Therefore, it is necessary to design the corresponding number of outer sides of the wire according to the specific requirements of the product.

[0065] In an optional implementation manner, S105: Laminate the insulating material 105 on the surfaces on both sides of the substrate body to make an insulation encapsulation layer (not marked in the figure); make a surface metal layer on the surface of the insulation encapsulation layer to form a printed circuit board.

[0066] The printed circuit board 100 can be a multi-layer printed circuit board 100. Metal wires 101 are arranged on one or more internal layers according to production requirements, or only on the surface metal layer 106 of the printed circuit board 100, or metal wires 101 are arranged on the entire board. In a specific embodiment, as Figure 5g shown, a printed circuit board 100 is formed with two layers of metal wires 101 arranged inside and surface metal layers 106 on both sides, and the product effect required for production is achieved according to the position of the arranged metal wires 101.

[0067] Please refer to Figure 6 and Figures 7a to 7j , Figure 6 is a schematic flow chart of the processing steps of another implementation manner of the manufacturing method of the printed circuit board of the present application, Figures 7a to 7j is a set of schematic structural diagrams of the processing steps of another implementation manner of the manufacturing method of the printed circuit board of the present application.

[0068] As Figure 6 shown, the present application provides a manufacturing method of a printed circuit board. The manufacturing method of the printed circuit board is used to prepare any one of the above-mentioned printed circuit boards 100.

[0069] The manufacturing method includes: S201: Prepare a metal sheet 102, and make a groove 103 on one side surface of the metal sheet 102 so that a metal block with the surface shape of the metal wire 101 is formed on the surface of the metal sheet 102. Among them, the groove 103 forming the metal block 104 is axisymmetric along the first symmetry axis, and the metal block 104 is axisymmetric along the first symmetry axis. The first symmetry axis is an axis passing through the center of the cross-section and perpendicular to the surface of the metal sheet 102.

[0070] The material of the metal sheet 102 can be a metal with good conductivity or low insertion loss such as copper, copper alloy, aluminum, aluminum alloy, etc. The thickness is determined according to the thickness of the processed copper foil or copper substrate, and the range is 0.5 oz to 2 oz. Specifically, it can be 0.5 oz, 1 oz, 1.5 oz, 2 oz, etc. Specifically, it is determined according to the requirements of the load current and the signal transmission requirements.

[0071] In an alternative embodiment, the groove 103 is formed by laser ablation, and the ablation degree of the laser is controlled to form a slope on the inclined groove, and the inclined groove includes one and / or more sloped surfaces.

[0072] In the processing area of a groove 103, the energies corresponding to laser ablation at positions with different depths are inconsistent. By controlling laser processing parameters such as the laser energy, the number of emissions, or the diameter of the laser, slopes with different depths and uniform changes can be achieved. Specifically, the processing direction of the groove 103 can be determined according to production requirements. In other embodiments, the groove 103 can be made by etching or machine etching. It can be understood that there is more than one metal wire 101 on the printed circuit board 100. In a specific embodiment, after all the grooves 103 on one side surface of the metal sheet 102 are made, the grooves 103 on the other side are made.

[0073] As Figure 7a shown, in this embodiment, grooves 103 with different slopes are made on one side surface of the metal sheet 102, so that the formed metal block 104 has a nearly round cross-sectional shape.

[0074] By making the groove 103, metal blocks 104 symmetric about the first axis of symmetry are formed on the metal sheet 102, so that the metal wires 101 formed after processing the metal blocks 104 are also figures symmetric about the first axis of symmetry, which can maintain the consistency and integrity during signal transmission, and can reduce the deformation caused by thermal expansion or mechanical stress during processing and use, improving the reliability of the printed circuit board 100.

[0075] As Figure 7b shown, S202: Place the surfaces of two metal sheets 102 with grooves 103 facing each other, and press them with the insulating material 105 so that the insulating material 105 fills the grooves 103.

[0076] The two metal sheets 102 are fixed by the insulating material 105, which provides support and fixation when processing the grooves 103 on the other side of the metal sheet 102, and an insulating layer (not marked in the figure) is provided between the two metal wires 101 formed subsequently, which can effectively save processes and processing costs.

[0077] In an alternative embodiment, S203: Tin is plated on the surface of the metal sheet 102 opposite to the side where the insulating material 105 is pressed, and the tin layer is ablated by laser in the projection area where the groove 103 is set to expose the surface of the metal sheet 102.

[0078] As Figure 7c shown, by plating tin on the surface of the metal sheet 102 and then processing, the tin layer can be effectively used to protect the surface of the metal sheet 102. As Figure 7dAs shown, after ablating the tin layer, the surface of the monitoring board is further processed on this basis, which can effectively improve the processing accuracy of the groove 103 of the metal plate 102. The laser energy for ablating the tin layer and the metal plate 102 can be the same or different, depending on the material of the metal plate 102. In other embodiments, the groove 103 on the surface of the tin-plated side of the metal plate 102 can be formed by etching, and setting the tin layer can protect the part outside the processing area of the metal plate 102.

[0079] As Figure 7e shown, S204: Make the same groove on the surface of the side of the metal plate 102 opposite to the pressed insulating material 105, so that metal blocks 104 with the surface shape of the metal wire 101 are formed on both surfaces of the metal plate 102. Among them, the grooves 103 on both surfaces of the metal plate 102 are axisymmetric about the second symmetry axis, and the formed metal blocks 104 are axisymmetric about the second symmetry axis. The second symmetry axis is the axis passing through the center of the cross-section and parallel to the surface of the metal plate 102.

[0080] Making the metal blocks 104 formed on both surfaces of a metal plate 102 axisymmetric about the second symmetry axis through the groove 103 can make the metal wire 101 formed after processing the metal blocks 104 also axisymmetric about the second symmetry axis.

[0081] As Figure 7f shown, S205: Remove the tin layer. It can be removed by a tin-removing liquid that does not react with the metal plate 102. After removing the tin layer, the entire surface of the metal plate 102 is exposed. In an alternative embodiment, the groove 103 is an inclined groove, the side wall of the inclined groove is perpendicular to the surface of the metal plate 102, and the ratio range of the depth to the width of the inclined groove is 1:1 to 1:1.5. The ratio of the depth to the width of the inclined groove is an important factor affecting the shape of the metal block 104. Specifically, the ratio range of the depth to the width of the inclined groove is 1:1, 1:1.2, 1:1.3, 1:1.4, 1:1.5.

[0082] In an alternative embodiment, the depth of the grooves 103 on both surfaces of the metal plate 102 is 10% - 20% of the thickness of the metal wire 101.

[0083] The range of a single groove 103 can be 10%, 12%, 15%, 16%, 18%, 20%, etc. of the thickness of the metal wire 101. The depths of the grooves 103 corresponding to metal wires 101 with different line widths and thicknesses are also different. It can be understood that when the thickness of the metal wire 101 is relatively thin, the depth of the groove 103 needs to be reduced so that the side wall of the metal wire 101 has a certain length to ensure that the side wall of the metal wire 101 can be better pressed and encapsulated with the insulating material 105.

[0084] S206: Develop and etch the metal sheet 102 to expose the insulating material 105, forming a substrate body with metal wires. The cross-sectional shape of the metal wire 101 along the axial direction is a polygon, and the number of sides of the polygon is greater than four.

[0085] As Figure 7g shown, cover the wet film on the metal sheet 102, expose the wet film, cure the wet film in the projection area of the metal wire 101, and the wet film in the part to be removed is not cured, and then perform etching to form as Figure 7h shown, the metal wire 101 fixed on the insulating material 105, and perform stripping treatment on the developing film covering the metal wire 101 to form a substrate body 107 with the metal wire 101 as Figure 7i shown.

[0086] Then perform subsequent production operations on the substrate body 107, such as insulation encapsulation, metal plating, etching, etc., to form the final printed circuit board 100.

[0087] Among them, the polygonal interface shape of the metal wire 101 can be a pentagon, hexagon, octagon, decagon, dodecagon, etc. Effectively increasing the number of outer sides of the metal wire 101 makes the metal wire 101 as round as possible, which can effectively reduce the insertion loss. However, the increase in the number of sides during the processing process also increases the processing steps and processing costs accordingly. Therefore, it is necessary to design the corresponding number of outer sides of the wire according to the specific requirements of the product.

[0088] In an alternative embodiment, S207: Press the insulating material 105 on the surfaces on both sides of the substrate body to fabricate an insulation encapsulation layer (not labeled in the figure); fabricate a surface metal layer on the surface of the insulation encapsulation layer to form a printed circuit board.

[0089] The printed circuit board 100 can be a multi-layer printed circuit board 100. Metal wires 101 are arranged on one or more internal layers according to production requirements, or metal wires 101 are only arranged on the metal layer on the surface of the printed circuit board 100, or metal wires 101 are arranged on the entire board. In a specific embodiment, as Figure 7j shown, a printed circuit board 100 is formed with two layers of metal wires 101 arranged inside and surface metal layers 106 on both sides, and the product effect required for production is achieved according to the positions of the arranged metal wires 101.

[0090] Please refer to Figure 8 and Figures 9a to 9c , Figure 8 which is a schematic flow diagram of the processing steps of another embodiment of the method for manufacturing a printed circuit board according to the present application, Figures 9a to 9c and is a set of schematic structural diagrams of the processing steps of another embodiment of the method for manufacturing a printed circuit board according to the present application.

[0091] As Figure 8 shown, wherein, the manufacturing method of the printed circuit board is used to prepare any one of the above-mentioned printed circuit boards 100.

[0092] The manufacturing method includes: S301: Prepare a metal sheet 102, and make a groove 103 on one side surface of the metal sheet 102, so that a metal block 104 with the surface shape of a metal wire is formed on the surface of the metal sheet 102. Among them, the groove 103 forming the metal block 104 is axisymmetric along the first axis of symmetry, the metal block 104 is axisymmetric along the first axis of symmetry, and the first axis of symmetry is an axis passing through the center of the cross-section and perpendicular to the surface of the metal sheet 102;

[0093] S302: Oppositely arrange the surfaces of two metal sheets 102 provided with grooves 103, and press them with an insulating material so that the insulating material fills the grooves 103.

[0094] S303: Make the same grooves on the surface of the metal sheet 102 opposite to the side where the insulating material is pressed, so that metal blocks 104 with the surface shape of metal wires are formed on both surfaces of the metal sheet 102. Among them, the grooves 103 on both surfaces of the metal sheet 102 are axisymmetric along the second axis of symmetry, and the formed metal blocks 104 are axisymmetric along the second axis of symmetry. The second axis of symmetry is an axis passing through the center of the cross-section and parallel to the surface of the metal sheet 102.

[0095] S304: Develop and etch the metal sheet 102 to expose the insulating material 105, and form a substrate body with metal wires 101. Among them, the cross-sectional shape of the metal wire 101 in the axial direction is a polygon, and the number of sides of the polygon is greater than four.

[0096] In this embodiment, steps S301 to S304 for forming the substrate body 107 can refer to S201, S202, S206, and S207 for forming the substrate body 107 in the processing steps of another embodiment of the manufacturing method of the printed circuit board 100 of the present application, and will not be elaborated here.

[0097] In an optional embodiment, insulating materials 105 are pressed on both surfaces of the substrate body 107 to make an insulating encapsulation layer (not labeled in the figure); a surface metal layer 106 is made on the surface of the insulating encapsulation layer to form the printed circuit board 100.

[0098] Among them, in an optional embodiment, as Figure 9a shown, S305: Make a groove 103 on the surface of the metal sheet 102.

[0099] In order to make the metal wire 101 of the present application on the surface metal layer 106, it is necessary to first make the outer shape of the metal wire 101 on the surface of the surface metal layer 106 close to the insulating material 105.

[0100] As shown Figure 9b in Figure 9b , S306: Press the surface provided with the groove 103 onto the surface of the insulating encapsulation layer away from the substrate body to form a surface metal layer. It can be understood that the method of forming the surface metal layer 106 can refer to the processing step S202 of another embodiment of the manufacturing method of the printed circuit board in this application.

[0101] As shown Figure 9c in Figure 9c , S307: Make a groove 103 on the surface of the surface metal layer so that metal wires are provided on the surface of the printed circuit board. It can be understood that the specific steps of making the groove 103 on the surface of the surface metal layer 106 can refer to S201 or S203 - S205 of the processing steps of another embodiment of the manufacturing method of the printed circuit board in this application, and the groove 103 is made by means of etching, laser ablation or machine tool etching.

[0102] The printed circuit board 100 can be a multi - layer printed circuit board 100. Metal wires 101 are arranged on one or more internal layers according to production requirements, or metal wires 101 are only arranged on the metal layer on the surface of the printed circuit board 100, or metal wires 101 are arranged on the whole board. In a specific embodiment, a printed circuit board 100 is formed with two layers of metal wires 101 arranged inside and a double - sided surface metal layer 106 having metal wires 101, and the product effect required by production is achieved according to the position of the arranged metal wires 101.

[0103] By the above - mentioned method, a printed circuit board and a manufacturing method of the printed circuit board are provided. By using the method of making grooves to gradually form metal wires with a cross - sectional shape of a polygon and the number of sides of the polygon being greater than four, the insertion loss can be effectively reduced, the transmission efficiency and signal integrity can be improved, the structure can be kept simple, the production cost can be reduced, the production requirements can be met, so that the printed circuit board 100 can withstand high - power usage requirements and meet the production requirements.

[0104] In several embodiments provided in the present application, it should be understood that the disclosed systems and devices can be implemented in other ways. For the technical solutions in the embodiments of the present application, obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application. For example, the described device embodiments above are only illustrative. For example, the division of the modules or units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be in electrical, mechanical or other forms.

[0105] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present application, then the directional indications are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0106] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "coupled", "connected", "joined", "set", "installed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0107] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0108] In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present application.

[0109] The above are only the embodiments of the present application, and do not thus limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall similarly be included within the patent protection scope of the present application.

Claims

1. A printed circuit board, characterized in that: A metal wire is arranged inside and / or on the surface of the printed circuit board; the cross-sectional shape of the metal wire along the axial direction is a polygon, and the number of sides of the polygon is greater than four; Among them, the metal wire is axially symmetrical along a first symmetry axis and a second symmetry axis; the first symmetry axis is an axis passing through the center of the cross section and perpendicular to the surface of the printed circuit board, and the second symmetry axis is an axis passing through the center of the cross section and parallel to the surface of the printed circuit board.

2. The printed circuit board according to claim 1, characterized in that: The cross-section shape of the metal wire is an octagon.

3. A method for manufacturing a printed circuit board, characterized in that: The method for manufacturing a printed circuit board is used to prepare the printed circuit board according to claim 1 or 2, and the method comprises: Prepare a metal plate, and make a groove on one side of the metal plate so that a metal block having the shape of the surface of the metal wire is formed on the surface of the metal plate; The groove forming the metal block is axially symmetrical along a first symmetry axis, and the metal block is axially symmetrical along the first symmetry axis, and the first symmetry axis is an axis passing through the center of the cross section and perpendicular to the surface of the metal plate; Place the surfaces of the two metal plates provided with the grooves facing each other, and press them together using the insulating material so that the insulating material fills the grooves; The same groove is made on the surface of the metal plate opposite to the side where the insulating material is pressed, so that metal blocks with the shape of the surface of the metal wire are formed on both sides of the metal plate; The grooves on both sides of the metal plate are axially symmetrical along a second symmetry axis, and the formed metal block is axially symmetrical along the second symmetry axis, and the second symmetry axis is an axis passing through the center of the cross section and parallel to the surface of the metal plate; The metal plate is developed and etched to expose the insulating material, thereby forming a substrate body with the metal wire, wherein the cross-sectional shape of the metal wire along the axial direction is a polygon, and the number of sides of the polygon is greater than four.

4. The method for manufacturing a printed circuit board according to claim 3, characterized in that: The manufacturing method includes: the groove is an oblique groove, the side wall of the oblique groove is perpendicular to the surface of the metal plate, and the ratio of the depth to the width of the oblique groove is in the range of 1:1 to 1:1.

5.

5. The method for manufacturing a printed circuit board according to claim 3 or 4, characterized in that: The manufacturing method comprises: the depth of the grooves on the two side surfaces of the metal plate is 10% to 20% of the thickness of the metal wire.

6. The method for manufacturing a printed circuit board according to claim 4, characterized in that: The manufacturing method comprises: the groove is formed by laser ablation, and the ablation degree of the laser is controlled so that the inclined groove forms an inclined surface with a slope, and the inclined groove includes one and / or multiple inclined surfaces with a slope.

7. The method for manufacturing a printed circuit board according to claim 3, characterized in that: The step of making the same groove on the surface of the metal plate opposite to the side where the insulating material is pressed, so that metal blocks with the shape of the surface of the metal wire are formed on both sides of the metal plate comprises: The surface of the metal plate opposite to the side where the insulating material is pressed is tin-plated, and the tin layer is ablated in the projection area where the groove is set by laser to expose the surface of the metal plate; after making the same groove on the surface, the tin layer is removed.

8. The method for manufacturing a printed circuit board according to claim 3, characterized in that: The step of developing and etching the metal plate to expose the insulating material and form a substrate body with the metal wires comprises: Insulating materials are pressed onto the surfaces of both sides of the substrate body to form an insulating packaging layer; A surface metal layer is manufactured on the surface of the insulating packaging layer to form the printed circuit board.

9. The method for manufacturing a printed circuit board according to claim 8, characterized in that: The step of packaging the substrate body surface by pressing the insulating material comprises: The insulating material is used to press the substrate body onto the surface of the substrate body to form multiple layers of the metal wires.

10. The method for manufacturing a printed circuit board according to claim 8, characterized in that: The step of manufacturing a surface metal layer on the surface of the insulating packaging layer so that the metal wire is arranged inside the printed circuit board comprises: Making the groove on the surface of the metal plate; Pressing the surface provided with the groove onto the surface of the insulating packaging layer away from the substrate body to form a surface metal layer; The groove is made on the surface of the surface metal layer so that the metal wire is arranged on the surface of the printed circuit board.

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