Circuit board
By designing a protective layer with partition covering and hollow structure on the circuit board, the problem of foreign objects scratching or extrusion during the tape reel is solved, and the protection of the circuit and the yield rate are improved.
Patent Information
- Application Number
- CN202410286677.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-02-06
- Filing Date
- 2024-03-13
- Publication Date
- 2025-08-08
AI Technical Summary
During the conveying or reeling of the existing circuit board, foreign objects scratch or squeeze the circuit, resulting in damage to the external pins and test pads, resulting in the substrate unit being detected as a defective product.
A circuit board structure is designed, wherein the circuit is divided into a first wire segment, a second wire segment and a third wire segment. The protective layer covers the first and third wire segments, reveals the second wire segment, and a hollow part is provided between the wire segments. The predetermined cutting line passes through the hollow part to separate the finished product and the part to be removed. The second protective part of the protective layer covers the third wire segment to avoid scratching and squeezing of foreign objects.
Effectively prevent foreign objects from scratching or squeezing the circuit, avoiding the generation of tin whiskers, and ensuring the normal transportation and processing of the circuit board.
Smart Images
Figure CN120456404A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a circuit board, in particular to a flexible circuit board which prevents circuits from being scratched or squeezed by foreign objects. Background Art
[0002] See also Figure 1 A conventional circuit board tape T1 includes a plurality of substrate units 10. The substrate unit 10 includes a carrier board 11, a plurality of circuits 12, and a protective layer 13. The circuits 12 have inner pins 12a, outer pins 12b, and a test pad 12c. The outer pins 12b are located between the inner pins 12a and the test pad 12c. The protective layer 13 covers the plurality of circuits 12 and exposes the inner pins 12a, the outer pins 12b, and the test pad 12c.
[0003] When the circuit board tape T1 is being conveyed or reeled, foreign matter (not shown, such as metal particles / debris, ink particles / debris, etc. generated in the process environment) remaining on the circuit board tape T1 may scratch the exposed external pins 12b and the test pads 12c, or cause the external pins 12b and the test pads 12c to be squeezed, generating tin whiskers or deformation, thereby causing the substrate unit 10 to be detected as defective. Summary of the Invention
[0004] The main purpose of the present invention is to provide a circuit board that can prevent foreign matter remaining on the circuit board (such as metal particles / debris, ink particles / debris, etc. generated in the process environment) from scratching the circuit boards when the circuit boards are rolled up or conveyed, and can prevent the circuit boards from being squeezed and generating tin whiskers.
[0005] A circuit board of the present invention includes a carrier, multiple circuits and a protective layer. The carrier has a surface. Along a first direction of conveying the circuit board, the surface includes a first area, a second area and a third area. The second area is located between the first area and the third area. Each of the circuits includes a first wire segment arranged in the first area, a second wire segment arranged in the second area and a third wire segment arranged in the third area. The second wire segment is located between the first wire segment and the third wire segment, and the second wire segment connects the outer pin of the first wire segment and the third wire segment. The protective layer covers the first wire segment and the third wire segment of the multiple circuits and exposes the second wire segment, the inner pin of the first wire segment and the outer pin.
[0006] Preferably, the protective layer includes a first protective portion, at least one second protective portion and a hollow portion, the hollow portion is located between the first protective portion and the second protective portion, the protective layer covers the first wire segment with the first protective portion, and exposes the inner pin and the outer pin of the first wire segment, the protective layer covers the third wire segment with the second protective portion, the hollow portion exposes the second wire segment, and the outer pin is exposed in the hollow portion, the predetermined cutting line passes through the hollow portion and is located between the first protective portion and the second protective portion, so that the circuit board is divided into a finished product portion and a portion to be removed, the outer pin of the first wire segment is located between the first protective portion and the predetermined cutting line, the first wire segment of each circuit and the first protective portion covering the first wire segment are located in the finished product portion, the second wire segment, the third wire segment and the second protective portion covering the third wire segment are located in the portion to be removed.
[0007] Preferably, the second protection portion exposes the test pad of the third wire segment.
[0008] Preferably, the protection layer includes two second protection portions, and the first protection portion is located between the two second protection portions.
[0009] Preferably, along the first direction, there is a first distance between the first protection portion and the second protection portion, and the first distance is not less than 0.5 um and not more than 2 um.
[0010] Preferably, the second protection portion exposes the test pad of the third wire segment, and along the first direction, there is a second distance between the second protection portion and the end of the test pad, and the second distance is not less than 0.5 um and not more than 2 um.
[0011] Preferably, the second protection portion has an appearance of a continuous geometric shape.
[0012] Preferably, the appearance of the second protection portion is a discontinuous geometric shape, and the second protection portion includes a plurality of protrusions. Along a second direction intersecting with the first direction, there is a third distance between two adjacent protrusions, and the third distance is not less than 0.5um and not more than 158mm.
[0013] Preferably, the second protection portion has a discontinuous geometric shape, and includes a plurality of protrusions. Along the first direction, there is a fourth distance between two adjacent protrusions, and the fourth distance is not less than 0.5 um and not more than 50 mm.
[0014] Preferably, the second protective portion covers the upper surface and side surfaces of the third wire segment and the surface of the carrier between the two third wire segments, and the second protective portion covering the upper surface of the third wire segment has a thickness that is not less than 0.5um and not more than 50um.
[0015] Preferably, the circuit has a copper layer and a tin layer, and the tin layer is located between the copper layer and the second protection portion.
[0016] Preferably, the appearance of the second protective portion is a continuous geometric shape or a discontinuous geometric shape, and the second protective portion has a first edge and a second edge, the first edge is closer to the first protective portion than the second edge, and there is a fifth distance between the first edge and the second edge, and the fifth distance is not less than 0.5um and not more than 50mm.
[0017] The present invention prevents foreign matter remaining on the circuit board from scratching the exposed outer pin of the first wire segment and the second wire segment by virtue of the protective layer covering the third wire segment being higher than the circuit, and prevents the exposed second wire segment and the outer pin from being squeezed to generate tin whiskers. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 : A schematic diagram of a conventional circuit board tape.
[0019] Figure 2 : Schematic diagram of the circuit board tape of the present invention.
[0020] Figure 3 : A schematic diagram of a circuit board of the present invention.
[0021] Figure 4A and Figure 4B : A schematic diagram of a circuit board of the present invention.
[0022] Figure 5 :Along Figure 3 Cross-sectional view along line AA.
[0023] Figure 6 : A partial cross-sectional view of a circuit board tape of the present invention being wound up.
[0024]
Main component symbol description
[0025] 10: Baseboard unit 11: Carrier board
[0026] 12: Line 12a: Inner pin
[0027] 12b: External pin 12c: Test pad
[0028] 13: Protective layer 100: Circuit board
[0029] 100a: Finished product part 100b: Part to be removed
[0030] 110: carrier board 111: surface
[0031] 111a: First zone 111b: Second zone
[0032] 111c: Third Zone 120: Line
[0033] 120a: copper layer 120b: tin layer
[0034] 121: first wire segment 121a: inner pin
[0035] 121b: External pin 122: Second wire segment
[0036] 123: third wire segment 123a: test pad
[0037] 123b: upper surface 123c: side surface
[0038] 130: Protective layer 131: First protective portion
[0039] 132: Second protection portion 132a: Convex body
[0040] 132b: first edge 132c: second edge
[0041] 133: hollow portion 140: planned cutting line
[0042] G1: First distance G2: Second distance
[0043] G3: third distance G4: fourth distance
[0044] G5: Fifth distance T1: Circuit board tape
[0045] T2: PCB tape X: Second direction
[0046] Y: first direction DETAILED DESCRIPTION
[0047] See also Figure 2 and Figure 3 A circuit board tape T2 includes multiple circuit boards 100, each of which includes a carrier board 110, multiple circuits 120, and a protective layer 130. The material of the carrier board 110 can be selected from materials such as polyimide (PI). The carrier board 110 has a surface 111. Along a first direction Y in which the circuit boards 110 are conveyed, the surface 111 includes a first area 111a, a second area 111b, and a third area 111c. The second area 111b is located between the first area 111a and the third area 111c.
[0048] See also Figure 2 、 Figure 3 and Figure 5The plurality of circuits 120 are provided on the surface 111. The material of the circuits 120 can be selected from copper and other materials. In this embodiment, the circuits 120 have a copper layer 120a and a tin layer 120b. The tin layer 120b covers the copper layer 120a. Each of the circuits 120 includes a first wire segment 121, a second wire segment 122 and a third wire segment 123. The second wire segment 122 is located between the first wire segment 121 and the third wire segment 123, and the second wire segment 122 is connected to the first wire segment 121 and the third wire segment 123. The outer pin 121b of the first wire segment 121 is connected to the third wire segment 123. The first wire segment 121 has an inner pin 121a. In this embodiment, the third wire segment 123 has a test pad 123a. The first wire segment 121 is disposed in the first area 111a, the second wire segment 122 is disposed in the second area 111b, and the third wire segment 123 is disposed in the third area 111c. The inner pin 121a is used to connect to an electronic component (not shown, such as a chip).
[0049] See also Figure 2 and Figure 3 The protective layer 130 covers the first wire segment 121 and the third wire segment 123 of the multiple circuits 120, and exposes the second wire segment 122, the inner pin 121a of the first wire segment 121, the outer pin 121b and the test pad 123a of the third wire segment 123. The material of the protective layer 130 can be selected from green paint (Solder Mask) and other materials.
[0050] See also Figure 2 and Figure 3 The protective layer 130 includes a first protective portion 131, at least one second protective portion 132 and a hollow portion 133. In this embodiment, the protective layer 130 includes two second protective portions 132, and the first protective portion 131 is located between the two second protective portions 132, but this is not a limitation. The hollow portion 133 is located between the first protective portion 131 and the second protective portion 132.
[0051] See also Figure 3 and Figure 5 The protective layer 130 covers the first wire segment 121 with the first protective portion 131, exposing the inner pin 121a and the outer pin 121b. The protective layer 130 covers the third wire segment 123 with the second protective portion 132, exposing the test pad 123a. In this embodiment, the second protective portion 132 covers the tin layer 120b, and the tin layer 120b is located between the copper layer 120a and the second protective portion 132. The hollow portion 133 located between the first protective portion 131 and the second protective portion 132 exposes the second wire segment 122 located between the first wire segment 121 and the third wire segment 123.
[0052] See also Figure 3 and Figure 5 The second protection portion 132 covers the upper surface 123 b and the side surface 123 c of the third wire segment 123 and the surface 111 of the carrier 110 located between the two third wire segments 123. The second protection portion 132 covering the upper surface 123 b of the third wire segment 123 has a thickness D, which is not less than 0.5 μm and not more than 50 μm, so that the height of the second protection portion 132 is higher than the height of the circuit 120.
[0053] See also Figure 3 The first wire segment 121 is connected to the second wire segment 122 via the outer pin 121 b , the first protection portion 131 exposes the outer pin 121 b , and the outer pin 121 b is exposed in the hollow portion 123 .
[0054] See also Figure 3 Along the second direction X intersecting with the first direction Y, the predetermined cutting line 140 passes through the hollow portion 133. The predetermined cutting line 140 is located between the first protection portion 131 and the second protection portion 132, and the outer lead 121b is located between the first protection portion 131 and the predetermined cutting line 140. In this embodiment, the predetermined cutting line 140 surrounds the first area 111a, so that the circuit board 100 is divided into a finished product portion 100a and a to-be-removed portion 100b. The first wire segment 121 of each circuit 120 and the outer lead covering the first wire segment 121 are The first protection portion 131 is located in the finished portion 100a, and the second wire segment 122, the third wire segment 123, and the second protection portion 132 covering the third wire segment 123 are located in the to-be-removed portion 100b. During the cutting process, the circuit board 100 is cut along the predetermined cutting line 140 by a cutting tool (not shown) to separate the finished portion 100a and the to-be-removed portion 100b, and the first wire segment 121 of each of the circuits 120 is disconnected from the second wire segment 122, and the external pin 121b is retained in the finished portion 100a.
[0055] See also Figure 3 Along the first direction Y, there is a first distance G1 between the first protection portion 131 and the second protection portion 132, and the first distance G1 is not less than 0.5um and not more than 2um. There is a second distance G2 between the second protection portion 132 and the end of the test pad 123a, and the second distance G2 is not less than 0.5um and not more than 2um.
[0056] See also Figure 3 and Figure 4AThe appearance of the second protection portion 132 is a continuous geometric shape. The appearance of the second protection portion 132 can be selected from regular or irregular geometric shapes such as straight lines, curves, and squares, or, please refer to Figure 4B The second protection portion 132 has a discontinuous geometric shape. The second protection portion 132 includes a plurality of protrusions 132a. The plurality of protrusions 132a can be selected from regular or irregular geometric shapes such as rectangles and circles. Along the second direction X, there is a third distance G3 between two adjacent protrusions 132a. The third distance G3 is not less than 0.5um and not more than 158mm. Along the first direction Y, there is a fourth distance G4 between two adjacent protrusions 132a. The fourth distance G4 is not less than 0.5um and not more than 50mm. Please refer to Figure 3 Along the first direction Y, the second protecting portion 132 has a first edge 132b and a second edge 132c. The first edge 132b is closer to the first protecting portion 131 than the second edge 132c. There is a fifth distance G5 between the first edge 132b and the second edge 132c. The fifth distance G5 is not less than 0.5um and not more than 50mm.
[0057] See also Figure 2 、 Figure 3 、 Figure 5 and Figure 6 When the circuit board tape T2 is being conveyed or reeled, the second protection portion 132 disposed on the third area 111 c and the third conductor segment 123 is higher than the circuit 120. This prevents foreign matter (not shown, such as metal particles / debris, ink particles / debris, etc. generated in the process environment) remaining on the circuit board 100 from scratching the outer lead 121 b of the first conductor segment 121, the second conductor segment 122, and the test pad 123 a of the third conductor segment 123. This also prevents the outer lead 121 b of the first conductor segment 121, the second conductor segment 122, and the test pad 123 a of the third conductor segment 123 of the circuit board 100 from being squeezed and generating tin whiskers.
[0058] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.
Claims
1. A circuit board, characterized in that: Include: A carrier having a surface, along a first direction of conveying the circuit board, the surface comprising a first area, a second area, and a third area, wherein the second area is located between the first area and the third area; a plurality of circuits, each of the circuits comprising a first wire segment disposed in the first region, a second wire segment disposed in the second region, and a third wire segment disposed in the third region, the second wire segment being located between the first wire segment and the third wire segment, and the second wire segment connecting an external pin of the first wire segment and the third wire segment; and The protection layer covers the first conductive line segment and the third conductive line segment of the plurality of circuits, and exposes the second conductive line segment, the inner pin of the first conductive line segment, and the outer pin.
2. The circuit board according to claim 1, wherein The protective layer includes a first protective portion, at least one second protective portion and a hollow portion, the hollow portion is located between the first protective portion and the second protective portion, the protective layer covers the first wire segment with the first protective portion, and exposes the inner pin and the outer pin of the first wire segment, the protective layer covers the third wire segment with the second protective portion, the hollow portion exposes the second wire segment, and the outer pin is exposed in the hollow portion, a predetermined cutting line passes through the hollow portion and is located between the first protective portion and the second protective portion, so that the circuit board is divided into a finished product portion and a portion to be removed, the outer pin of the first wire segment is located between the first protective portion and the predetermined cutting line, the first wire segment of each circuit and the first protective portion covering the first wire segment are located in the finished product portion, the second wire segment, the third wire segment and the second protective portion covering the third wire segment are located in the portion to be removed.
3. The circuit board according to claim 2, characterized in that The second protection portion exposes the test pad of the third wire segment.
4. The circuit board according to claim 2, characterized in that The protection layer includes two second protection portions, and the first protection portion is located between the two second protection portions.
5. The circuit board according to claim 2 or 3, characterized in that Along the first direction, a first distance exists between the first protection portion and the second protection portion, and the first distance is not less than 0.5 um and not more than 2 um.
6. The circuit board according to claim 5, characterized in that The second protection portion exposes the test pad of the third wire segment. Along the first direction, a second distance exists between the second protection portion and an end of the test pad. The second distance is not less than 0.5 um and not more than 2 um.
7. The circuit board according to claim 2, characterized in that The second protection portion has an appearance of a continuous geometric shape.
8. The circuit board according to claim 2, characterized in that The appearance of the second protection portion is a discontinuous geometric shape. The second protection portion includes a plurality of protrusions. Along a second direction intersecting with the first direction, there is a third distance between two adjacent protrusions, and the third distance is not less than 0.5um and not more than 158mm.
9. The circuit board according to any one of claims 2, 3 and 8, characterized in that: The second protection portion has a discontinuous geometric shape. The second protection portion includes a plurality of protrusions. Along the first direction, there is a fourth distance between two adjacent protrusions. The fourth distance is not less than 0.5 μm and not more than 50 mm.
10. The circuit board according to claim 2, characterized in that The second protection portion covers the upper surface and side surfaces of the third wire segment and the surface of the carrier between the two third wire segments. The second protection portion covering the upper surface of the third wire segment has a thickness that is not less than 0.5um and not more than 50um.
11. The circuit board according to claim 10, characterized in that The circuit has a copper layer and a tin layer, and the tin layer is located between the copper layer and the second protection portion.
12. The circuit board according to claim 2, characterized in that The appearance of the second protective portion is a continuous geometric shape or a discontinuous geometric shape. The second protective portion has a first edge and a second edge. The first edge is closer to the first protective portion than the second edge. There is a fifth distance between the first edge and the second edge. The fifth distance is not less than 0.5um and not more than 50mm.