CN212259431U - Anti-electromagnetic interference flexible circuit board structure - Google Patents
Anti-electromagnetic interference flexible circuit board structure Download PDFInfo
- Publication number
- CN212259431U CN212259431U CN202020878378.2U CN202020878378U CN212259431U CN 212259431 U CN212259431 U CN 212259431U CN 202020878378 U CN202020878378 U CN 202020878378U CN 212259431 U CN212259431 U CN 212259431U
- Authority
- CN
- China
- Prior art keywords
- circuit board
- flexible circuit
- board body
- layer
- conductive adhesive
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Structure Of Printed Boards (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The utility model provides an anti-electromagnetic interference flexible circuit board structure, belonging to the field of flexible circuit board manufacturing, comprising a flexible circuit board body and two shielding layers which are respectively pressed on the upper side and the lower side of the flexible circuit board body; the flexible circuit board body comprises a base material, a copper foil layer and a covering film; the covering film is provided with a window; a through hole is formed in a preset position on the flexible circuit board body; the shielding layer comprises a conductive adhesive layer and an insulating layer; the conductive adhesive layers are respectively contacted with two sides of the flexible circuit board body, and the two conductive adhesive layers are communicated in the open hole. Preferably, the flexible circuit board body is a single-sided flexible circuit board, and the opening is a non-metal through hole. The manufacturing process is simple, the production efficiency and the product yield are optimized, the material cost is saved, and the anti-electromagnetic interference effect can be met.
Description
Technical Field
The utility model relates to a flexible circuit board (FPC) makes the field, especially relates to a structure of flexible circuit board that can anti-electromagnetic interference.
Background
FPC is a Flexible Printed circuit board (Flexible Printed Circuits) for short, and is a light, thin, and bendable Printed circuit board. The flexible circuit board is divided into different structural types such as single-layer, double-layer (up to 6 layers), multi-layer and the like.
The flexible circuit board can encounter electromagnetic interference phenomenon in the design and application process, especially the functional flexible circuit board, and the electromagnetic Shielding (EMI Shielding) performance is an important evaluation index. Therefore, it is necessary to connect a grounding layer to the front and back (upper and lower) surfaces of the manufactured flexible printed circuit board for shielding and anti-interference. At present, the conventional method is to place a signal layer of a flexible circuit board in a middle layer, and add a ground layer on the upper and lower sides of the flexible circuit board to be connected with a ground wire in a middle circuit to play a role in shielding against electromagnetic interference, so that a structure mode of at least three layers of flexible circuit boards needs to be manufactured, and the manufacturing difficulty and cost of the flexible circuit boards are increased. In another method, a conductive shielding layer is added on the upper and lower surfaces of the manufactured flexible circuit board for anti-electromagnetic interference, and the shielding layer needs to be communicated with the ground wire inside the flexible circuit board. In order to achieve the anti-electromagnetic interference effect, a pth (plated through hole) is required to be processed on the flexible circuit board, i.e., a through hole is plated, and a layer of thin copper is plated on the non-metal hole wall. The circuit on the upper surface and the circuit on the lower surface are communicated through the plated through hole, and then the covering films on the upper and lower surfaces are punched by using a die to form windows. The shielding layer pressed on the upper surface of the FPC is communicated with the ground wire in the circuit through the windowing of the covering film on the upper surface of the flexible circuit board, and the shielding layer pressed on the lower surface of the FPC is communicated with the ground wire in the circuit board through the windowing of the covering film on the lower surface of the flexible circuit board, so that a copper conductor circuit is formed through PTH electroplating, the purpose of forming a conductor loop between layers is achieved, further the conduction between the upper shielding layer and the lower shielding layer is achieved, and the effect of resisting electromagnetic interference is achieved. In this method, the process for processing PTH is difficult and requires strict quality control. The material cost is increased invisibly, and the working procedure is more complex. The conventional complete production flow for manufacturing such an emi-resistant flexible circuit board structure includes: blanking → drilling hole → PTH electroplating via hole → chemical cleaning → dry film → film alignment double-sided circuit → exposure → development → etching → film removal → punching → chemical cleaning → blanking two-layer cover film → pressing → baking → sand blasting → nickel electroplating-nickel blanking-two-layer shielding layer → pressing → baking → printing characters → baking → cutting mold division → shape one-time punching → electrical testing → shape two-time punching → FQC → FQA → packaging warehousing and shipment.
Therefore, in order to optimize production resource allocation, improve the yield and production efficiency of the flexible circuit board and meet the preset requirement of anti-electromagnetic interference, it is necessary to design an anti-electromagnetic interference flexible circuit board structure, simplify the process, save the cost and be beneficial to improving the product yield.
Disclosure of Invention
The utility model relates to a solve above-mentioned problem and go on, aim at provides an anti-electromagnetic interference flexible circuit board structure, optimizes process flow, simple manufacture, practices thrift the cost, and production efficiency is high, can satisfy anti-electromagnetic interference's requirement and with low costs.
The utility model provides an anti-electromagnetic interference flexible circuit board structure, which comprises a flexible circuit board body and an upper and a lower shielding layers pressed on the upper and the lower sides of the flexible circuit board body; the flexible circuit board body comprises a base material, and a copper foil layer and a covering film which are sequentially overlapped on the surface of the base material; the covering film is provided with a window; a through hole is formed in a preset position on the flexible circuit board body; the shielding layer comprises a conductive adhesive layer and an insulating layer; the shielding layer is pressed on the covering film, and the conductive adhesive layers are respectively contacted with two sides of the flexible circuit board; the conductive adhesive of the conductive adhesive layer is in contact with the copper foil of the copper foil layer exposed in the window; and the conductive adhesive on the two sides of the conductive adhesive layer is contacted in the opening. The conductive adhesive layer of the upper shielding layer and the conductive adhesive layer of the lower shielding layer are exposed out of the conductive adhesive of the opening to realize electrical connection, namely, the upper shielding layer and the lower shielding layer are conducted. And the upper shielding layer and/or the lower shielding layer are/is communicated with the ground wire of the flexible circuit board body through the window of the covering film, so that the flexible circuit board body, the upper shielding layer and the lower shielding layer are/is communicated.
After the conductive adhesive is cured or dried, an electrical path can be formed between the connected materials. In the structure, the shielding layer is pressed, so that the conductive adhesive of the shielding layer is filled in the open holes penetrating through the upper side and the lower side of the flexible circuit board body and is exposed to the other side. The upper and lower conductive adhesive layers are connected through the conductive adhesive in the open holes, so that electrical connection of each layer is realized, the arrangement of a connection circuit is saved, a metal conductive material is saved to a certain extent, and the process difficulty is also reduced.
Specifically, the opening is a non-metal outer hole, namely a non-electroplating through hole, namely the opening is not required to be processed by electroplating conductive metal; the number and the positions of the holes can be set according to the actual production condition. The processing technology is greatly simplified, the more complicated flow steps are also saved, the yield reduction of the finished product of the flexible circuit board caused by the unqualified technology of processing the Plated Through Hole (PTH) is avoided, the inspection process of the plated through hole structure in the quality inspection is also saved, and the production efficiency is optimized.
Preferably, the flexible circuit board body is a single-sided flexible circuit board, that is, a copper foil layer is arranged on one surface of the substrate, and a cover film is attached to the copper foil layer. A signal line area and a grounding line area are arranged on the copper foil layer; the windowing part is arranged corresponding to the grounding wire area; and the conductive adhesive of the conductive adhesive layer is communicated with the copper foil in the window, so that the shielding layer is conducted with the grounding wire area of the flexible circuit board body. With a single-sided flexible circuit board, wiring is provided on only one surface of a substrate. The double-sided flexible circuit board needs double-sided wiring, and a few circuits are arranged on one side of the double-sided flexible circuit board only for conducting with one shielding layer, so that the material utilization rate is low, and great material waste is caused; in addition, two times of alignment are needed in the film alignment process, the probability of error prone in alignment is high, and the working time spent in the step is long. Because the through holes are formed, the upper shielding layer and the lower shielding layer can be mutually conducted through the conductive adhesive and are electrically communicated with the flexible circuit board body, the upper shielding layer and the lower shielding layer can be pressed on two sides of the single-sided flexible circuit board to achieve the effect of resisting electromagnetic interference of the flexible circuit board, double-sided wiring is not necessary, the material cost is saved, and the workload of film alignment is reduced.
In a specific implementation, the opening is correspondingly disposed at a position of the ground line region.
In a better implementation mode, the plurality of windows are arranged at positions far away from the edge of the flexible circuit board body. The covering film around the window far away from the edge can keep enough supporting effect, and the situation that the edge part of the flexible circuit board body is easy to be broken under stress is avoided.
The utility model relates to an anti-electromagnetic interference flexible circuit board structure, through the trompil that link up about the flexible circuit board body sets up, conductive adhesive layer's conducting resin is in the upper and lower shielding layer's of switching on has been realized to the exposure in the trompil. The single-sided flexible circuit board is adopted as the flexible circuit board body, and the signal wire area and the grounding wire area are arranged on the copper foil layer on one surface, so that the utilization rate of circuit materials is improved, and the production efficiency is optimized. The open pore is a non-electroplating through hole, so that the process is greatly simplified, the arrangement is easy, and the improvement of the production efficiency and the yield of finished products is facilitated.
Drawings
Fig. 1 is a schematic diagram of a layered structure for anti-electromagnetic interference protection of a flexible circuit board in the prior art.
Fig. 2 is a schematic diagram of a layered structure of the flexible printed circuit board with anti-electromagnetic interference according to an embodiment of the present invention.
In the figure: 1-a flexible circuit board body; 10-a substrate; 11-copper foil layer; 12-a cover film; 121-a polyimide film; 122-a binder; 123-windowing; 13-copper electroplating; 14-plating through holes; 15-outer shape hole; 2-a shielding layer; 21-a conductive adhesive layer; 22-insulating layer.
Detailed Description
In order to make the technical means, creation characteristics, achievement purpose and efficiency of the utility model easily understand and understand, the following embodiment combines the drawings to do the utility model discloses an anti-electromagnetic interference flexible circuit board structure does specifically expounds.
In order to achieve the effect of resisting electromagnetic interference, a conventional method is to add a shielding layer 2 on the surface of a manufactured flexible circuit board body 1 as shown in fig. 1. In a general flexible circuit board body 1, a copper foil layer 11 is disposed on each of the upper and lower surfaces of a substrate 10, and a signal line area and a ground line area are formed on the copper foil layer 11. The coverlay film 12 is typically a polyimide film 121 coated with an adhesive 122, and two coverlay films 12 are attached to the two copper foil layers 11 on the upper and lower surfaces of the substrate 10. The cover films 12 on both sides are provided with a plurality of windows 123 for exposing the circuits of the copper foil layer 11. The shielding layer 2 is composed of an insulating layer 22 and a conductive adhesive layer 21. The conductive adhesive of the conductive adhesive layer 21 contacts the copper foil circuit of the copper foil layer 11 exposed in the window 123, and conducts the shielding layer 2 and the copper foil layer 11. In order to realize electromagnetic shielding, the upper and lower shielding layers need to be conducted with each other. In the prior art, a plated through hole 14 is processed on a flexible circuit board body 1, that is, a blind hole is made to penetrate through a copper foil layer 11 and a substrate 10, metal, generally copper plating, is plated around a hole wall and a hole edge, and an upper surface circuit and a lower surface circuit are conducted with each other through a copper conductor, and the blind hole is a blind hole below a cover film 12. The process for manufacturing the plated through hole 14 is complex, and upper and lower line conduction needs to be achieved through the processes of drilling, black hole, copper plating and the like, so that the manufacturing period is increased. As mentioned above, the prior art needs approximately 27 conventional production process steps to complete the addition of the shielding layer to the flexible circuit, and the process requirement is high, which also increases the workload and difficulty for quality inspection.
In an embodiment of the present invention, as shown in fig. 2, the flexible circuit board 1 is a single-sided flexible circuit board, i.e. a copper foil layer 11 is disposed on one surface of a substrate 10 and a cover film 12 is attached thereon. Also, a plurality of windows 123 are provided on the cover film 12, and fig. 2 shows only 2 windows 123, which is merely an illustration and is not limited to 2. In this embodiment, the opening window 123 is correspondingly disposed on the ground line region of the copper foil layer 11 and is far away from the edge of the flexible circuit board body 1, and the periphery of the opening window 123 is sufficiently supported by the cover film 12. Firstly, the shielding layer 2 is pressed on one side of the flexible circuit board body 1, and the shielding layer 2 is conducted with the copper foil circuit of the copper foil layer 11 through the window 123. The flexible circuit board body 1 has the opening, i.e., the outline hole 15 in the present embodiment, penetrating through the cover film 12, the copper foil layer 11, and the base material 10. Only one external hole 15 is shown in fig. 2, which is only an illustration and not limiting the number of external holes 15, the number and layout of external holes 15 can be preset according to the actual production situation. In this embodiment, the outer hole 15 is formed at a portion of the ground line region provided on the flexible circuit board body 1. The actual flexible circuit board body 1 is very thin, the longitudinal depth of the outline hole 15 is very small, so when the shielding layer 2 is pressed, the conductive adhesive of the conductive adhesive layer 22 is pressed into the outline hole 15 to fill the outline hole 15 and is exposed to the other side of the flexible circuit board body 1, then another shielding layer 2 is pressed onto the other surface of the substrate 10 without wiring, namely the other side of the flexible circuit board body 1, and the conductive adhesive of the conductive adhesive layer 22 of the other shielding layer 2 is also pressed into the outline hole 15. The conductive adhesive layers 22 of the two shielding layers 2 laminated on the two sides of the flexible circuit board body 1 are communicated through the conductive adhesive in the outer hole 15, namely, the two shielding layers 2 on the two sides are mutually communicated. Meanwhile, the shielding layer 2 is electrically conducted with the copper foil layer 11 of the flexible circuit board body 1 through the window 123, so that the shielding layers 2 and the flexible circuit board body 1 in the middle are mutually conducted. Because both sides have all set up shielding layer 2 about flexible circuit board body 1 to two-layer shielding layer 2 switches on each other, just can form a complete shielding and keep apart flexible circuit board body 1 and the outside electromagnetism in the middle of with, fine protection flexible circuit board does not receive electromagnetic interference.
The process of processing the flexible circuit board with anti-electromagnetic interference in the embodiment includes blanking → pasting a dry film → a film alignment side circuit → exposure → development → etching → stripping → punching → chemical cleaning → blanking a layer of cover film → pressing → baking → sandblasting → nickel electroplating → blanking two layers of shielding layer → pressing → baking → printing characters → baking → cutting with a knife mold → first punching of the shape → electrical testing → second punching of the shape → FQC → FQA → packaging and warehousing and shipment. It can be easily found that the conduction between the two shielding layers 2 is realized by connecting the conductive adhesive of the conductive adhesive layer 22 in the outer shape hole 15, so that the conduction between the shielding layers 2 is not affected by the absence of the plated metal in the outer shape hole 15. As long as there is one layer of shielding layer 2 to conduct with the grounding circuit of the flexible circuit board body 1, the two layers of shielding layer 2 and the flexible circuit board body 1 are conducted with each other. The film contraposition also has only one contraposition single side. Therefore, the production process is reduced, the manufacturing time efficiency is improved, and the material cost is greatly saved. As can be seen from the comparison of the process flow, the processing of the utility model discloses a step that anti-electromagnetic interference flexible circuit board structure can be saved includes drilling, PTH electroplating via hole, chemical cleaning. The quality inspection steps of the PTH are correspondingly simplified, and in addition, the films in the embodiment are only aligned on one surface, so that the alignment error probability is reduced, the operation is simpler, and the efficiency is higher. In the present embodiment, the conductive adhesive layer 22 is made of a matrix resin and a conductive filler, but is not limited to this, and may contain an adhesive agent of metal conductive particles. The insulating layer 21 in this embodiment is made of rubber, which is not limited, and other insulating materials may be selected according to actual conditions of enterprises.
Therefore, the utility model discloses can realize anticipated technological effect.
It should be noted that, in the following description, the terms "upper" and "lower" are used only for convenience of description with reference to the drawings, and are not intended to limit the present invention.
The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
Claims (4)
1. The utility model provides an anti-electromagnetic interference flexible circuit board structure which characterized in that: the shielding layer comprises a flexible circuit board body and two shielding layers which are respectively pressed on the upper side and the lower side of the flexible circuit board body; the flexible circuit board body comprises a base material, a copper foil layer and a covering film, wherein the copper foil layer and the covering film are sequentially stacked on the surface of the base material; the covering film is provided with a window; a through hole is formed in a preset position on the flexible circuit board body; the shielding layer comprises a conductive adhesive layer and an insulating layer; the conductive adhesive of the conductive adhesive layer is in contact with the copper foil of the copper foil layer exposed in the window; and the conductive adhesive on the two sides of the conductive adhesive layer is contacted in the opening.
2. An anti-electromagnetic interference flexible circuit board structure according to claim 1, characterized in that: the flexible circuit board body is a single-sided flexible circuit board; a signal wire area and a grounding wire area are arranged on the copper foil layer; the windowing on the cover film is arranged corresponding to the grounding wire area.
3. An anti-electromagnetic interference flexible circuit board structure according to claim 1 or 2, characterized in that: the opening is a non-metallic external aperture.
4. An anti-electromagnetic interference flexible circuit board structure according to claim 1 or 2, characterized in that: the windowing is multiple and is arranged at a position far away from the edge of the flexible circuit board body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020878378.2U CN212259431U (en) | 2020-05-22 | 2020-05-22 | Anti-electromagnetic interference flexible circuit board structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020878378.2U CN212259431U (en) | 2020-05-22 | 2020-05-22 | Anti-electromagnetic interference flexible circuit board structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212259431U true CN212259431U (en) | 2020-12-29 |
Family
ID=73975181
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020878378.2U Active CN212259431U (en) | 2020-05-22 | 2020-05-22 | Anti-electromagnetic interference flexible circuit board structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212259431U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112996230A (en) * | 2021-02-03 | 2021-06-18 | 厦门天马微电子有限公司 | Windowing transfer film, flexible circuit board and manufacturing method of windowing transfer film |
-
2020
- 2020-05-22 CN CN202020878378.2U patent/CN212259431U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112996230A (en) * | 2021-02-03 | 2021-06-18 | 厦门天马微电子有限公司 | Windowing transfer film, flexible circuit board and manufacturing method of windowing transfer film |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8042265B2 (en) | Method for manufacturing multilayer flexible printed circuit board | |
| CN108966478B (en) | Flexible circuit board and manufacturing method thereof | |
| KR100499008B1 (en) | Two-sided PCB without via hole and the manufacturing method thereof | |
| TWI478642B (en) | Printed circuit board with embedded component and method for manufacturing same | |
| CN110798988B (en) | Additive process for manufacturing high-frequency antenna packaging substrate and AiP packaging antenna structure | |
| CN103763854A (en) | Printed circuit board and manufacturing method thereof | |
| CN104244582A (en) | Embedded type high-density interconnection printed circuit board and manufacturing method of embedded type high-density interconnection printed circuit board | |
| EP1942711B1 (en) | Method of manufacturing a wiring board including electroplating | |
| TWI693004B (en) | Rigid-flex circuit board and method for making the same | |
| US10292279B2 (en) | Disconnect cavity by plating resist process and structure | |
| CN212259431U (en) | Anti-electromagnetic interference flexible circuit board structure | |
| CN107041078A (en) | The manufacture method of high density flexible substrate | |
| CN104219876A (en) | Circuit board and manufacture method thereof | |
| CN108156763B (en) | Transparent circuit board and manufacturing method thereof | |
| CN107172800B (en) | PCB for antenna radio frequency transmission and manufacturing method thereof | |
| CN107820362B (en) | Hollow flexible circuit board and manufacturing method thereof | |
| CN112449494B (en) | Manufacturing method of printed circuit board | |
| CN105592620A (en) | Circuit board and manufacturing method thereof | |
| CN114286516B (en) | Manufacturing method of tail-separating ladder electric-thickness golden finger soft and hard combined plate | |
| TWI462660B (en) | Printed circuit board and method for manufacturing same | |
| CN110062538B (en) | Manufacturing method of PCB (printed circuit board) with lead at bottom of stepped groove and PCB | |
| KR100993318B1 (en) | Method for manufacturi ng flying tail type rigid-flexible printed circuit board | |
| CN104902698A (en) | A circuit board golden finger processing method and a circuit board having golden fingers | |
| KR101368043B1 (en) | Structure of double-sided flexible printed circuit board | |
| CN211457534U (en) | Fine interlayer circuit structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |