Circuit board and method of manufacturing the same

Abstract

A manufacturing method of a circuit board, comprising the steps of: providing a copper-clad substrate, the copper-clad substrate comprising a substrate layer and a copper foil layer disposed on the substrate layer, the copper-clad substrate being provided with an opening, the opening penetrating the substrate layer and exposing part of the copper foil layer at the bottom of the opening; disposing a conductive body in the opening, the conductive body electrically connecting the copper foil layer; etching the copper foil layer to form a flexible circuit layer, thereby obtaining the circuit board, wherein the flexible circuit layer comprises a plurality of connection pads and a plurality of bending lines, the connection pads are arranged at intervals, the bending lines are connected between every two connection pads, the length of the bending lines is greater than the straight-line distance between every two adjacent connection pads, and part of the connection pads are electrically connected to the conductive body. In addition, the application further provides a circuit board.

Description

Technical Field

[0001] This application relates to a circuit board and a method for manufacturing the same. Background Technology

[0002] With the popularization of 5G technology, the market share of consumer electronics and wearable products is gradually increasing. In particular, emerging technology products such as foldable screen phones, AR / VR / MR, and smart clothing are developing rapidly. The circuit boards used in such electronic products need to withstand high-frequency bending during normal electrical transmission. Under normal circumstances, the lines in the bending area are designed in straight lines, and the bending area cannot be designed with vias or SMT components. Therefore, the dynamic bending performance of the circuit board is severely restricted. Furthermore, because the bending area cannot be equipped with vias or SMT components, the high-density advantage of the circuit board is severely limited. Summary of the Invention

[0003] To address the problems in the background art, this application provides a method for manufacturing a circuit board.

[0004] In addition, this application also provides a circuit board.

[0005] A method for manufacturing a circuit board includes the steps of: providing a copper-clad substrate, the copper-clad substrate including a substrate layer and a copper foil layer disposed on the substrate layer, the copper-clad substrate having an opening penetrating the substrate layer, and a portion of the copper foil layer being exposed at the bottom of the opening; disposing a conductor within the opening, the conductor electrically communicating with the copper foil layer; and etching the copper foil layer to form a flexible circuit layer to obtain the circuit board. The flexible circuit layer includes a plurality of connecting pads and a plurality of bent lines, the plurality of connecting pads being spaced apart, the bent lines connecting every two connecting pads, each bent line including at least a first line segment and a second line segment connecting the first line segment, the angle between the first line segment and the second line segment being 120°, each connecting pad including a first end and a second end opposite to the first end, two first line segments respectively connecting to the first ends of two adjacent connecting pads, and two second line segments respectively connecting to the second ends of two adjacent connecting pads, a portion of the connecting pad being electrically connected to the conductor.

[0006] Furthermore, the method includes the steps of: providing a cover layer on the flexible circuit layer, the cover layer having a window corresponding to the conductor, and providing an electronic component within the window, the electronic component being electrically connected to the conductor.

[0007] Furthermore, the method includes the step of etching another portion of the connection pad that is not electrically connected to the conductor to form an "S"-shaped circuit.

[0008] A circuit board includes a substrate layer, a conductor, and a flexible circuit layer. The substrate layer has an opening, and the conductor is disposed within the opening. The flexible circuit layer is disposed on the surface of the substrate layer and includes a plurality of connecting pads and a plurality of bent lines. The plurality of connecting pads are spaced apart, and the bent lines are connected between every two connecting pads. Each bent line includes at least a first line segment and a second line segment connecting the first line segment. The angle between the first line segment and the second line segment is 120°. Each connecting pad includes a first end and a second end opposite to the first end. Two first line segments are respectively connected to the first ends of two adjacent connecting pads, and two second line segments are respectively connected to the second ends of two adjacent connecting pads. Some of the connecting pads are electrically connected to the conductor.

[0009] Furthermore, two first line segments are correspondingly arranged between two adjacent connecting pads, and two second line segments are correspondingly arranged between two adjacent connecting pads.

[0010] Furthermore, the connecting pad is strip-shaped, and the first line segment, the second line segment, and the connecting pad are of equal length. Two adjacent connecting pads and two bent lines located between two adjacent connecting pads together form a regular hexagonal honeycomb structure.

[0011] Furthermore, the connecting pad includes a third end and a fourth end, the third end and the fourth end being electrically isolated, the bent circuit includes a third circuit segment, a fourth circuit segment and a fifth circuit segment connected between the third circuit segment and the fourth circuit segment, the ends of the two third circuit segments away from the fifth circuit segment are connected to the third ends of two adjacent connecting pads, and the ends of the two fourth circuit segments away from the fifth circuit segment are connected to the fourth ends of two adjacent connecting pads.

[0012] Furthermore, the two fifth line segments between two adjacent connecting pads are arranged in parallel relative to each other.

[0013] Furthermore, the flexible circuit layer also includes a connecting wire end, which is connected to the connecting pad.

[0014] Furthermore, it also includes a cover layer and electronic components. The cover layer is disposed on the flexible circuit layer and has a window. The electronic components are disposed in the window and are electrically connected to the conductor.

[0015] The circuit board provided in this application has a flexible circuit layer, which includes a plurality of spaced connecting pads and a bent circuit connecting each pair of adjacent connecting pads. The overall length of the bent circuit is greater than the straight distance between each pair of adjacent connecting pads. This allows the portion of the bent circuit that exceeds the straight distance between adjacent connecting pads to stretch slowly as the bending occurs, even when the bent circuit is subjected to external force. This reduces the risk of repeated bending fatigue caused by straight-line design and improves the overall flexibility of the circuit board. Attached Figure Description

[0016] Figure 1 This is a cross-sectional schematic diagram of the copper-clad substrate provided in an embodiment of this application.

[0017] Figure 2 for Figure 1 The diagram shows a cross-sectional view of the copper-clad substrate after the opening is set.

[0018] Figure 3 for Figure 2 The diagram shows a cross-section after a conductor is installed inside the opening.

[0019] Figure 4 For etching Figure 3 The diagram shown is a cross-sectional view of the copper foil layer after it has been used to form a flexible circuit layer. Figure 5 (Schematic diagram of a cross section along line IV-IV).

[0020] Figure 5 For etching Figure 3 The copper foil layer shown is a bottom view after it has been used to form a flexible circuit layer.

[0021] Figure 6 This is a bottom view of a flexible circuit layer provided in another embodiment of this application.

[0022] Figure 7 for Figure 4 The diagram shows a cross-sectional view of the flexible circuit layer after a cover film has been applied.

[0023] Figure 8 A schematic cross-sectional view of the circuit board provided in the embodiments of this application ( Figure 9 (Cross view along line VIII-VIII).

[0024] Figure 9 for Figure 8 Top view of the circuit board shown

[0025] Figure 10 This is a top view of a circuit board used in another embodiment of this application.

[0026] Explanation of main component symbols

[0027] Circuit board 100

[0028] Copper clad substrate 10

[0029] Substrate layer 11

[0030] Copper foil layer 12

[0031] Opening 21

[0032] Conductor 22

[0033] Flexible circuit layer 30

[0034] Connecting pad 31

[0035] First end 311

[0036] Second end 312

[0037] Third end 313

[0038] Fourth end 314

[0039] 32 bends

[0040] First line section 321

[0041] Second Line Section 322

[0042] Third Line Section 323

[0043] Section 324 of Line 4

[0044] Section 325 of Line 5

[0045] Connecting terminal 33

[0046] Covering membrane 41

[0047] Adhesive layer 411

[0048] Insulating ink layer 412

[0049] Window opening 413

[0050] Electronic Components 51

[0051] Main body part 511

[0052] Pin 512

[0053] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation

[0054] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0055] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or may also exist in an intervening component. When a component is considered to be "set on" another component, it can be directly set on the other component or may also exist in an intervening component.

[0056] Please see Figures 1 to 8 One embodiment of this application provides a method for manufacturing a circuit board 100, including the following steps:

[0057] S1: Please see Figure 1 A copper-clad substrate 10 is provided, the copper-clad substrate 10 including a substrate layer 11 and two copper foil layers 12, the two copper foil layers 12 being respectively disposed on opposite surfaces of the substrate layer 11. The substrate layer 11 is made of materials including, but not limited to, liquid crystal polymer (LCP), polytetrafluoroethylene (PTFE), poly(ether-ether-ketone) (PEEK), polyphenylene oxyethylene (PPO), polyimide (PI), polyethylene terephthalate (PET), and polyethylene naphthalate dimethyl ether glycol ester (PEN). Preferably, the substrate layer 11 is made of an elastic liquid crystal polymer.

[0058] S2: Please see Figure 2 An opening 21 is formed on the copper-clad substrate 10 by laser etching. The opening 21 penetrates one copper foil layer 12 and the substrate layer 11, with another copper foil layer 12 exposed at the bottom of the opening 21. In other embodiments of this application, the opening 21 can also be formed by drilling.

[0059] S3: Please see Figure 3 A conductor 22 is formed within the opening 21 by electroplating, and the conductor 22 electrically connects the two oppositely disposed copper foil layers 12. In other embodiments of this application, the conductor 22 can also be formed by filling with conductive paste.

[0060] S4: Please see Figure 4 Two copper foil layers 12 are etched to form a flexible circuit layer 30, and the two flexible circuit layers 30 are electrically connected through the conductor 22. See also... Figure 5The flexible circuit layer 30 includes a plurality of connecting pads 31 and a plurality of bent circuits 32. The plurality of connecting pads 31 are arranged in strips at intervals, and two bent circuits 32 are connected between each two adjacent connecting pads 31 to form a honeycomb structure. Specifically, the bent circuit 32 includes a first circuit segment 321 and a second circuit segment 322. The first circuit segment 321, the second circuit segment 322 and the connecting pads 31 are arranged in equal lengths, and the first circuit segment 321 and the second circuit segment 322 are connected at a 120-degree angle. The connecting pad 31 includes a first end 311 and a second end 312 disposed opposite to the first end 311. Two first line segments 321 are respectively connected to the first ends 311 of two adjacent connecting pads 31, and two second line segments 322 are respectively connected to the second ends 312 of two adjacent connecting pads 31. The two first line segments 321 disposed between two adjacent connecting pads 31 are correspondingly disposed, and the two second line segments 322 disposed between two adjacent connecting pads 31 are also correspondingly disposed, so that the two adjacent connecting pads 31 and the two bent lines 32 disposed between the two adjacent connecting pads 31 together form a regular hexagonal honeycomb structure.

[0061] Please see Figure 6 In another embodiment of this application, the connecting pad 31 includes a third end 313 and a fourth end 314, the third end 313 and the fourth end 314 being spaced apart (i.e., the third end 313 and the fourth end 314 being electrically isolated), and the bent line 32 includes a third line segment 323, a fourth line segment 324 and a fifth line segment 325 connected between the third line segment 323 and the fourth line segment 324. The ends of the two third line segments 323 away from the fifth line segment 325 are connected to the third ends 313 of the two adjacent connecting pads 31, and the ends of the two fourth line segments 324 away from the fifth line segment 325 are connected to the fourth ends 314 of the two adjacent connecting pads 31. The fifth line segments 325 between the two adjacent connecting pads 31 are arranged relatively parallel. Since the third ends 313 and the fourth ends 314 are electrically isolated, the two adjacent connecting pads 31 and the two bent lines 32 between the two adjacent connecting pads 31 together form two sets of electrically isolated arch bridge structures.

[0062] In other embodiments of this application, the first line segment 321, the second line segment 322, and the connecting pad 31 may also be of unequal length, and the shape enclosed by the two connecting pads 31 and the bent line 32 connecting the two connecting pads 31 may also be a polygon other than a hexagon. Furthermore, in other embodiments of this application, the bent line 32 may also be a curved segment. In fact, any other shape of bent line 32 that meets the condition that the total length of each bent line 32 is greater than the straight-line distance between each pair of adjacent connecting pads 31 can be used to connect two adjacent connecting pads 31.

[0063] In this embodiment, the flexible circuit layer 30 further includes a connecting terminal line 33, which connects to the connecting pad 31. The connecting terminal line 33 can be disposed in an area where bending is not required, and the flexible circuit layer 30 can be disposed in an area where bending is required.

[0064] In this embodiment, the manufacturing method further includes the step of:

[0065] S5: The etched portion is not electrically connected to the connecting pad 31 of the conductor 22 to form an "S" shaped line (not shown), which helps to increase the flexibility of the connecting pad 31.

[0066] S6: Please see Figure 7 An elastic cover film 41 is provided on both of the flexible circuit layers 30. The elastic cover film 41 includes an adhesive layer 411 and an insulating ink layer 412. The adhesive layer 411 is disposed between the insulating ink layer 412 and the flexible circuit layer 30. Part of the adhesive layer 411 is filled into the gap of the flexible circuit layer 30. The elastic cover film 41 can protect the flexible circuit layer 30. At the same time, when the elastic cover film 41 is subjected to external force and bends, it can undergo elastic deformation.

[0067] S7: Please see Figure 7 An opening 413 is provided on one of the elastic covering films 41, the opening 413 corresponding to the conductor 22, and a portion of the connecting pad 31 is exposed at the bottom of the opening 413. That is, the opening 413 corresponds to the portion of the connecting pad 31 connected to the conductor 22.

[0068] S8: Please see Figure 8 An electronic component 51 is disposed within the window 413, and the electronic component 51 is electrically connected to the connecting pad 31 to obtain the circuit board 100. The electronic component 51 includes capacitors, inductors, resistors, and integrated circuits, and the electronic component 51 can be connected to the connecting pad 31 by soldering.

[0069] Please see Figure 8 and Figure 9 In this embodiment, the electronic component 51 has a body portion 511 and two pins 512. The pins 512 are spaced apart from the body portion 511 and are electrically connected to the body portion 511. The two pins 512 are respectively disposed on two adjacent connecting pads 31.

[0070] Please see Figure 10 In another embodiment of this application, the two pins 512 of the electronic component 51 are located at the third end 313 and the fourth end 314 of the same connecting pad 31.

[0071] Please see Figure 8 and Figure 9 This application embodiment also provides a circuit board 100, which includes a substrate layer 11, a conductor 22, and a flexible circuit layer 30. The substrate layer 11 is provided with an opening 21, the conductor 22 is disposed in the opening 21, and the flexible circuit layer 30 is disposed on the surface of the substrate layer 11. The flexible circuit layer 30 includes a plurality of connecting pads 31 and a plurality of bent lines 32. The plurality of connecting pads 31 are spaced apart, and the bent lines 32 are connected between every two connecting pads 31. The length of the bent lines 32 is greater than the straight-line distance between every two adjacent connecting pads 31, and some of the connecting pads 31 are electrically connected to the conductor 22.

[0072] Compared with the prior art, the circuit board 100 provided in this application has the following advantages:

[0073] (i) By setting a flexible circuit layer 30, the flexible circuit layer 30 includes a plurality of spaced connecting pads 31 and a bent circuit 32 connecting each two adjacent connecting pads 31, and the overall length of the bent circuit 32 is greater than the straight distance between each two adjacent connecting pads 31, so that even if the bent circuit 32 is bent by an external force, the portion of the bent circuit 32 that exceeds the straight distance between the adjacent connecting pads 31 can be slowly stretched as the bending occurs, thereby reducing the risk of multiple bending fatigue caused by the straight design and improving the overall flexibility of the circuit board 100.

[0074] (ii) By setting multiple connecting pads 31, some connecting pads are connected to the conductor 22. These connecting pads 31 can be used to set electronic components 51, thereby increasing the density of the circuit board 100.

[0075] Please see Figure 5 or Figure 9In this embodiment, the connecting pad 31 includes a first end 311 and a second end 312 opposite to the first end 311. The bent line 32 includes a first line segment 321 and a second line segment 322 connecting the first line segment 321. The two first line segments 321 are respectively connected to the first ends 311 of two adjacent connecting pads 31, and the two second line segments 322 are respectively connected to the second ends 312 of the two connecting pads 31.

[0076] Please see Figure 6 or Figure 10 In another embodiment of this application, the connecting pad 31 includes a third end 313 and a fourth end 314, the third end 313 and the fourth end 314 being spaced apart (i.e., the third end 313 and the fourth end 314 are electrically isolated). The bent wire 32 includes a third wire segment 323, a fourth wire segment 324, and a fifth wire segment 325 connecting the third wire segment 323 and the fourth wire segment 324. The ends of the two third wire segments 323 away from the fifth wire segment 325 are connected to the third ends 313 of two adjacent connecting pads 31, and the ends of the two fourth wire segments 324 away from the fifth wire segment 325 are connected to the fourth ends 314 of two adjacent connecting pads 31. The fifth wire segments 325 between two adjacent connecting pads 31 are arranged relatively parallel.

[0077] The specific embodiments of this application have been described above with reference to the accompanying drawings. However, those skilled in the art will understand that various changes and substitutions can be made to the specific embodiments of this application without departing from the spirit and scope of this application. All such changes and substitutions fall within the scope defined by this application.

Claims

1. A method for manufacturing a circuit board, characterized in that, Including the following steps: A copper-clad substrate is provided, the copper-clad substrate including a substrate layer and a copper foil layer disposed on the substrate layer, the copper-clad substrate having an opening that penetrates the substrate layer, and a portion of the copper foil layer being exposed at the bottom of the opening; A conductor is provided within the opening, and the conductor is electrically connected to the copper foil layer; The copper foil layer is etched to form a flexible circuit layer to obtain the circuit board. The flexible circuit layer includes a plurality of connecting pads and a plurality of bent lines. The plurality of connecting pads are spaced apart. The bent lines are connected between every two connecting pads. Each bent line includes at least a first line segment and a second line segment connecting the first line segment. The angle between the first line segment and the second line segment is 120°. Each connecting pad includes a first end and a second end opposite to the first end. Two first line segments are respectively connected to the first ends of two adjacent connecting pads. Two second line segments are respectively connected to the second ends of two adjacent connecting pads. Part of the connecting pads are electrically connected to the conductor. The first line segment, the second line segment, and the connecting pads are of equal length. Two adjacent connecting pads and two bent lines located between two adjacent connecting pads together form a regular hexagonal honeycomb structure.

2. The manufacturing method as described in claim 1, characterized in that, It also includes the following steps: A cover layer is provided on the flexible circuit layer, the cover layer having a window corresponding to the conductor; and An electronic component is disposed within the window, and the electronic component is electrically connected to the conductor.

3. The manufacturing method as described in claim 1, characterized in that, It also includes the following steps: Etch another portion of the connection pad that is not electrically connected to the conductor to form an "S" shaped circuit.

4. A circuit board, characterized in that, The device includes a substrate layer, a conductor, and a flexible circuit layer. The substrate layer has openings, and the conductor is disposed within the openings. The flexible circuit layer is disposed on the surface of the substrate layer and includes multiple connecting pads and multiple bent circuits. The multiple connecting pads are spaced apart, and the bent circuits are connected between every two connecting pads. Each bent circuit includes at least a first circuit segment and a second circuit segment connecting the first circuit segment. The angle between the first circuit segment and the second circuit segment is 120°. Each connecting pad includes a first end and a second end opposite to the first end. Two first circuit segments are respectively connected to the first ends of two adjacent connecting pads, and two second circuit segments are respectively connected to the second ends of two adjacent connecting pads. Some of the connecting pads are electrically connected to the conductor. The first circuit segment, the second circuit segment, and the connecting pads are of equal length. Two adjacent connecting pads and two bent circuits disposed between two adjacent connecting pads together form a regular hexagonal honeycomb structure.

5. The circuit board as described in claim 4, characterized in that, Two first line segments are correspondingly arranged between two adjacent connecting pads, and two second line segments are also correspondingly arranged between two adjacent connecting pads.

6. The circuit board as described in claim 4, characterized in that, The connecting pad includes a third end and a fourth end, the third end and the fourth end are electrically isolated, the bent circuit includes a third circuit segment, a fourth circuit segment and a fifth circuit segment connected between the third circuit segment and the fourth circuit segment, the ends of the two third circuit segments away from the fifth circuit segment are connected to the third ends of the two adjacent connecting pads, and the ends of the two fourth circuit segments away from the fifth circuit segment are connected to the fourth ends of the two adjacent connecting pads.

7. The circuit board as described in claim 6, characterized in that, The two fifth line segments between two adjacent connecting pads are arranged in parallel relative to each other.

8. The circuit board as described in claim 4, characterized in that, The flexible circuit layer also includes a connecting wire end, which is connected to the connecting pad.

9. The circuit board as described in claim 4, characterized in that, The circuit board also includes a cover layer and electronic components. The cover layer is disposed on the flexible circuit layer and has a window. The electronic components are disposed in the window and are electrically connected to the conductor.

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