JP4333659B2 - Flexible wiring board - Google Patents

Description

  The present invention relates to a flexible wiring board having a terminal portion used for internal wiring of an electronic device or the like and wiring connection between electronic devices.

  In recent years, EMI (electromagnetic interference) countermeasures have become an important issue for electronic devices and the like. For example, when a circuit board inside an electronic device is connected to another circuit or the like, a flexible wiring substrate that is a cable serves as an antenna, and electromagnetic noise is radiated into and out of the electronic device, which becomes a serious problem.

  Conventionally, prevention of electromagnetic noise on a circuit board is achieved by connecting one electrode terminal of a chip capacitor, which is a filter element for EMI countermeasures, on the same plane as the circuit board or around a male connector for connecting a flexible wiring board, for example. This is performed by a filter circuit configuration such as connecting to a pin and grounding the other electrode terminal.

  In such a configuration, since a ground space for mounting a chip capacitor around the electronic component is required, it is extremely difficult to reduce the size of the electronic device.

  Further, there is a method for preventing electromagnetic noise by electromagnetically shielding the flexible wiring board itself, but this has led to an increase in the cost of the flexible wiring board.

  In order to solve these problems, a ground electrode, which is a solid electrode, is formed on the back side of the terminal portion of the base film in which the signal line and the ground line are formed on one side, and reinforcement for reinforcing the terminal portion on the ground electrode A flexible wiring board in which a plate is provided and a ground wire and a ground electrode are connected via a conductive via provided in a base film has been proposed (see, for example, Patent Document 1).

According to this, since the wiring of the terminal part for connecting with a connector is provided only on one surface, a short connector can be used. In addition, since a capacitor is formed between the signal line via the base film and the ground electrode to form a filter element, it is not necessary to separately provide a chip capacitor or the like on the circuit board, and the increase in the circuit board space can be reduced. ing.
JP-A-8-279667

  However, in the flexible wiring board shown in Patent Document 1 described above, since the base film is used as a dielectric, the capacitor capacity is determined by the area of the opposing wiring and the ground electrode, the thickness of the dielectric, and the dielectric constant, and any capacitor It is difficult to realize capacity. For this reason, there has been a limit to obtain the desired prevention performance against electromagnetic noise.

  Moreover, since the dielectric constant is determined by the material of the base film, there is a problem that the material used for the base film of the flexible wiring board is limited. Furthermore, since the thickness of the base film varies depending on the desired capacitor capacity, the thickness of the reinforcing plate must be designed accordingly, which has the problem of reduced productivity.

  The present invention has been made to solve the above-mentioned problems, and is a sheet member made of a sheet-like device that combines the function of preventing terminal noise and preventing electromagnetic noise while also preventing electromagnetic noise by setting an arbitrary capacitor capacity. An object of the present invention is to provide a flexible wiring board that can greatly improve the above-described characteristics.

  In order to solve the problems as described above, the flexible wiring board of the present invention has a base film in which a signal line and a ground line are formed on at least one surface, and on the other surface side of at least one end of the base film. The sheet member includes a terminal part having a sheet member, and the sheet member includes a sheet-like device in which a plurality of thin film capacitors connected to the signal line and the ground line are formed.

  The first electrode terminal of the thin film capacitor of the sheet-like device is connected to the ground line through the first conductive via provided in the base film, and the second electrode terminal of the thin film capacitor is provided in the second film provided on the base film. It may be connected to the signal line through the conductive via.

  As a result, since the sheet-like device serves as both the reinforcing portion and the filter element for preventing electromagnetic noise, the capacitor capacity can be arbitrarily set without depending on the material of the base film, and electromagnetic noise can be suppressed over a wide range. .

  Further, the flexible wiring board of the present invention includes a base film having a signal line and a ground line formed on at least one surface, and at least one tip portion of the base film is folded, and a sheet member is placed on the folded surface of the tip portion. The sheet member includes a sheet-like device in which a plurality of thin film capacitors connected to the signal line and the ground line are formed.

  Furthermore, the first electrode terminal of the thin film capacitor of the sheet-like device may be connected to the ground line, and the second electrode terminal of the thin film capacitor may be connected to the signal line.

  Accordingly, since the sheet-like device, the signal line, and the ground line are not connected via the conductive via, the flexible wiring board can be manufactured with high productivity by a simple process.

  Further, in the sheet-like device, thin film capacitors having a first electrode terminal and a second electrode terminal sandwiching a dielectric material may be formed in an array in a predetermined arrangement on one surface of a sheet-like substrate.

  Thereby, electromagnetic noise can be prevented at least for each signal line.

  Furthermore, signal lines and ground lines may be alternately arranged on the base film.

  Thereby, since the signal line is electromagnetically shielded by the adjacent ground line, crosstalk between the signal lines can be suppressed.

  According to the flexible wiring board of the present invention, the sheet member made of a sheet-like device can be used both as a terminal element reinforcement and a filter element for preventing electromagnetic noise. Furthermore, since the capacitor capacity can be set arbitrarily, it is possible to realize a flexible wiring board that is excellent in electromagnetic noise prevention performance.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
1A is a perspective view for explaining a main part of the flexible wiring board according to the first embodiment of the present invention. FIG. 1B is a cross-sectional view taken along the line AA in FIG. (C) is the BB sectional drawing of the figure (a).

  As shown in FIG. 1A, the flexible wiring board 100 according to the first embodiment of the present invention has a longitudinal direction 110 and a transverse direction (in this specification, a direction perpendicular to the longitudinal direction is expressed as a transverse direction). The same applies to the following. 130, for example, has at least four signal lines 2 and two ground lines 3 on one surface of the strip-shaped base film 1, for example. Here, an example in which the four signal lines 2 are formed between the two ground lines 3 in the short direction 130 is shown, but the present invention is not limited to this.

  The signal line 2 and the ground line 3 other than the terminal portion 8 of the flexible wiring board 100 are covered with a protective film 6 made of an insulating resin such as a resist.

  In the terminal portion 8, for example, a donut-shaped land 4 is formed at a predetermined position of the signal line 2. Similarly, for example, a donut-shaped land 5 is formed at a predetermined position of the ground line 3. Each land is formed in a predetermined size in order to surely connect with the conductive via described below, but it is not always necessary. In other words, this is not necessary when the conductive vias formed in the base film are securely connected with the widths of the signal lines and the ground lines.

  Furthermore, in the terminal part 8, the sheet | seat member 10 which consists of the sheet-like device 9 is affixed on the other surface of the base film 1, for example with an adhesive agent. In the following, when the electrical characteristics are shown, it is expressed as a sheet-like device 9, and when it shows mechanical characteristics such as reinforcement of the terminal portion, it is expressed as a sheet member 10. That is, the sheet member 10 can be a reinforcing member that reinforces the terminal portion 8.

  The sheet-like device 9 includes a first conductive via 11 formed in the base film 1 corresponding to the land 4 of the signal line 2 as shown in FIG. The second conductive vias 12 formed in the base film 1 corresponding to the lands 5 of the ground line 3 are electrically connected to each other.

  Here, the sheet-like device 9, which will be described in detail below, includes at least an arrayed thin film capacitor corresponding to the signal line 2, a first electrode terminal, and a second electrode terminal.

  With the above configuration, the flexible wiring board 100 according to the first embodiment of the present invention is obtained.

  Note that the signal line 2 and the ground line 3 are, for example, an etching method of a metal foil such as copper (Cu) or aluminum (Al) attached to the surface of the base film 1, a plating method, or a screen printing method such as a conductive paste. It is formed by.

  Moreover, as a material of the base film 1, for example, a film mainly composed of an insulating resin such as a polyimide film or polyester is used.

  Below, the structure of the sheet-like device in the 1st Embodiment of this invention is demonstrated using FIG.

  FIG. 2A is a perspective plan view for explaining the configuration of the sheet-like device 9 of the flexible wiring board in the first embodiment of the present invention, and FIG. 2B is the AA line in FIG. It is sectional drawing.

  As shown in FIG. 2, the sheet-like device 9 includes a first electrode terminal 22 and a second electrode on a sheet-like substrate 120 such as polyimide or polyphenylene sulfide (for example, 125 μm thick) with a dielectric film 170 interposed therebetween. The thin film capacitor 160 is provided with the electrode terminal 23. The sheet-like substrate 120 is preferably at least as large as the terminal portion of the flexible wiring substrate. A plurality of thin film capacitors 160 are formed in an array, for example, in accordance with the arrangement and number of signal lines and ground lines of the flexible wiring board. Here, the first electrode terminal 22 of each thin film capacitor 160 is provided at a position corresponding to the land 4 of the signal line 2 of the flexible wiring board 100, and is connected to an individual lower layer electrode 180 for each thin film capacitor 160. The second electrode terminal 23 corresponding to each thin film capacitor 160 is provided corresponding to the position of the land 5 of the ground line 3 of the flexible wiring board 100 and is connected to the upper layer electrode 190 that commonly connects the thin film capacitors 160. Is done.

  Then, an insulating protective film 200 is formed to protect the sheet-like device 9 except at least the first electrode terminal 22 and the second electrode terminal 23. At this time, the insulating protective film 200 is preferably not more than the height of the first electrode terminal 22 and the second electrode terminal 23.

  Below, the specific structural example and manufacturing method of the thin film device which comprises the sheet-like device 9 are demonstrated, referring FIG.

First, the thin film capacitor 160 has low resistance and good adhesion to the sheet substrate 120, for example, an aluminum (Al) lower layer electrode 180 and an upper layer electrode 190 are opposed to each other, and have a large relative dielectric constant, for example, silicon dioxide (SiO ₂ ). Or the like, with a dielectric film 170 interposed therebetween.

Here, the lower layer electrode 180 and the upper layer electrode 190 are formed to have a thickness of, for example, 1 μm, for example, by combining sputtering, vacuum deposition, plating, and the like. In addition to the silicon dioxide (SiO ₂ ), the dielectric film 170 is selected from, for example, barium titanate (BaTiO ₃ ), strontium titanate (SrTiO ₃ ), and the like. A predetermined film thickness is formed by a phase film formation method (PCVD method) or the like, for example, a thickness of 0.2 μm to 0.3 μm, and a predetermined capacitor capacitance value is obtained.

  Further, an insulating protective film 200 having excellent moisture resistance, for example, an epoxy resin having a thickness of about 10 μm is formed by a printing method so as to cover at least the dielectric film 170.

  In addition, the first electrode terminal 22 and the second electrode terminal 23 connected to the signal line 2 and the ground line 3 of the flexible wiring substrate 100 have a low electric resistance, for example, vacuum film formation using a sputtering method or the like such as copper (Cu). The conductive paste is formed on the lower electrode 180 by a screen printing method, for example, with a thickness of about 5 μm.

  In this way, the thin film capacitor 160 as the sheet-like device 9 can be set by arbitrarily setting the areas of the upper and lower electrodes facing each other, the dielectric constant of the dielectric film material, the film thickness of the dielectric film, etc. Capacitor capacitance values necessary to prevent electromagnetic noise in a wide frequency range can be obtained arbitrarily.

  Thereby, since the sheet-like device 9 can arbitrarily set and adjust the capacitor capacity, electromagnetic noise in a wide frequency range can be prevented.

  As described above, according to the first embodiment of the present invention, the sheet member 10 made of the sheet-like device 9 is used as a reinforcing member for mechanical reinforcement in the terminal portion 8 of the flexible wiring board 100. And at least a filter element capable of arbitrarily setting a capacitor capacity for preventing electromagnetic noise.

  Thereby, it is not necessary to stick a separate sheet member to the terminal portion of the flexible wiring board, and a flexible wiring board excellent in electromagnetic noise prevention performance can be obtained.

  In the first embodiment of the present invention, an example in which a sheet member made of a sheet-like device is provided in one terminal portion of the flexible wiring board is not limited thereto. For example, as shown in an electric equivalent circuit diagram illustrating another example of the flexible wiring board in FIG. 3, the sheet-like device 9 including the capacitors 31 and 32 may be provided at the terminal portions 8 at both ends of the flexible wiring board 100. Good. Thereby, the prevention performance of the electromagnetic noise of a flexible wiring board can further be improved.

  In the first embodiment of the present invention, the thin film capacitors of the sheet-like device have been described as having the same size, but the present invention is not limited to this. For example, when one of the signal lines is a power supply line or the like, a thin film capacitor having a larger capacitor capacity may be formed by increasing the shape or the like than a thin film capacitor connected to another signal line. Accordingly, electromagnetic noise or the like can be efficiently prevented for each signal line corresponding to the transmission speed (frequency) of the signal transmitted through the signal line.

(Second Embodiment)
Below, the flexible wiring board in the 2nd Embodiment of this invention is demonstrated in detail using FIG.

  FIG. 4A is a perspective plan view for explaining a main part of the flexible wiring board according to the second embodiment of the present invention, and FIG. 4B is a cross-sectional view taken along line AA of FIG. 4 (c) is a cross-sectional view taken along line BB in FIG. In addition, the same code | symbol is used for the same component as FIG. 1, and description is abbreviate | omitted.

  In FIG. 4, the terminal portion formed by folding the vicinity of the end portion of the flexible wiring board is provided with a sheet member on the surface on which the signal line is formed on the front end side of the folded terminal portion. Is different.

  As shown in FIG. 4, the flexible wiring board 400 according to the second embodiment of the present invention is formed on one surface of a base film 41 such as a strip-shaped polyimide, which is indicated by a longitudinal direction 110 and a lateral direction 130. At least, for example, four signal lines 42 and two ground lines 43 are provided.

  Then, the sheet member 50 made of the sheet-like device 49 is applied to the front end portion 44 side of the base film 41 where the signal line 42 is exposed, by, for example, thermocompression bonding or the like. The electrode terminal 52 and the second electrode terminal 53 are connected. Further, as shown in FIG. 4B, the base film 41 in the portion where the sheet member 50 is provided is folded, and the other surfaces of the base film 41 are bonded to each other with an adhesive or the like, for example. Form. In the following, when the electrical characteristics are shown, it is expressed as a sheet-like device 49, and when it shows mechanical characteristics such as reinforcement of the terminal portion, it is expressed as a sheet member 50. That is, the sheet member 50 can be a reinforcing member that reinforces the terminal portion 48.

  At this time, the sheet-like device 49 includes a signal line 42 and a first electrode terminal 52 as shown in FIG. 4B, and a ground line 43 and a second electrode terminal 53 as shown in FIG. Electrically connected.

  Further, the signal line 42 and the ground line 43 other than the terminal portion 48 of the flexible wiring board 400 form and cover a protective film 46 made of an insulating resin such as a resist.

  Here, as will be described in detail below, the sheet-like device 49 includes at least an array of thin film capacitors corresponding to the number of signal lines 42, first electrode terminals, and second electrode terminals.

  With the above configuration, the flexible wiring board 400 according to the second embodiment of the present invention is obtained.

  The signal line 42 and the ground line 43 are formed by the same method as in the first embodiment. Further, the same material as that of the first embodiment can be used for the material of the base film 41 and the like.

  Below, the structure of the sheet-like device in the 2nd Embodiment of this invention is demonstrated using FIG.

  FIG. 5A is a perspective plan view for explaining the configuration of the sheet-like device 49 of the flexible wiring board according to the second embodiment of the present invention, and FIG. 5B is the AA line of FIG. It is sectional drawing.

  As shown in FIG. 5, the sheet-like device 49 includes, for example, a first electrode terminal 52 and a second electrode on a sheet-like substrate 120 such as polyimide or polyphenylene sulfide (for example, a thickness of 125 μm) with a dielectric film 170 interposed therebetween. A thin film capacitor 460 having an electrode terminal 53 is included. The sheet substrate 120 is preferably at least as large as the terminal portion 48 of the flexible wiring substrate 400. A plurality of thin film capacitors 460 are formed in an array, for example, in accordance with the arrangement and number of signal lines 42 and ground lines 43 of the flexible wiring board 400. Here, the first electrode terminal 52 of each thin film capacitor 460 is provided corresponding to the position of the signal line 42 of the flexible wiring board 400, and is connected to the individual lower layer electrode 180 for each thin film capacitor 460. The second electrode terminal 53 corresponding to each thin film capacitor 460 is provided corresponding to the position of the ground line 43 of the flexible wiring board 400 and is connected to the upper layer electrode 190 that commonly connects the thin film capacitors 460. .

  Then, an insulating protective film 200 is formed in order to protect the sheet-like device 49 except at least the first electrode terminal 52 and the second electrode terminal 53. At this time, the insulating protective film 200 is preferably equal to or less than the height of the first electrode terminal 52 and the second electrode terminal 53.

  Since the thin film capacitor 460 of the sheet-like device 49 can be formed in the same manner as in the first embodiment, description thereof is omitted.

  As described above, according to the second embodiment of the present invention, the sheet member 50 made of the sheet-like device 49 is used as a reinforcing member for mechanical reinforcement at the terminal portion 48 of the flexible wiring board 400. And at least a filter element capable of arbitrarily setting a capacitor capacity for preventing electromagnetic noise. That is, the terminal portion 48 formed by attaching the sheet-like device 49 to the folded distal end portion 44 functions as a male connector, and is fitted and connected to a separately prepared female connector (not shown). Is.

  Thereby, it is not necessary to stick a separate sheet member to the terminal portion of the flexible wiring board, and a flexible wiring board excellent in electromagnetic noise prevention performance can be obtained.

  In addition, according to the second embodiment of the present invention, the first electrode terminal 52 connected to the signal line 42 and the ground line 43 respectively in the terminal portion 48 of the flexible wiring board 400 without providing the conductive vias. A sheet-like device 49 functioning as a filter element incorporating a thin film capacitor having the second electrode terminal 53 can be provided.

  Thereby, while being excellent in productivity, the flexible wiring board cheap and excellent in the connection reliability with a sheet-like device is obtained.

  Below, the modification of the flexible wiring board in the 2nd Embodiment of this invention is demonstrated using FIG. 6 and FIG.

  FIG. 6A is a perspective plan view for explaining a main part in a modified example of the flexible wiring board according to the second embodiment of the present invention, and FIG. 6B is an AA line in FIG. Sectional drawing and FIG.6 (c) are the BB sectional drawing of the figure (a). FIG. 7A is a perspective plan view for explaining the configuration of the sheet-like device 49 in a modified example of the flexible wiring board according to the second embodiment of the present invention, and FIG. It is an AA sectional view taken on the line. In addition, the same code | symbol is used for the same component as FIG. 4, FIG. 5, and description is abbreviate | omitted.

  6 is different from FIG. 4 in that the signal lines and the ground lines of the flexible wiring board are alternately provided, and the first electrode terminals and the second electrode terminals of the thin film capacitor are alternately arranged correspondingly. It is.

  As shown in FIG. 6A, a flexible wiring board 600 according to a modification of the second embodiment of the present invention has a base film such as a strip-shaped polyimide, which is indicated by a longitudinal direction 110 and a lateral direction 130, for example. For example, three signal lines 62 and four ground lines 63 are alternately arranged on one surface of 61.

  Then, the sheet member 70 made of the sheet-like device 69 is applied to the front end portion 64 side of the base film 61 where the signal line 62 is exposed, for example, by thermocompression bonding or the like. The electrode terminal 72 and the second electrode terminal 73 are connected. Further, as shown in FIG. 6B, the terminal film 68 is formed by folding the portion of the base film 61 where the sheet member 70 is provided and bonding the other surfaces of the base film 61 with, for example, an adhesive. Form. In the following, when the electrical characteristics are shown, it is expressed as a sheet-like device 69, and when it shows mechanical characteristics such as reinforcement of the terminal portion, it is expressed as a sheet member 70. That is, the sheet member 70 can be a reinforcing member that reinforces the terminal portion 68.

  At this time, the sheet-like device 69 includes a signal line 62 and a first electrode terminal 72 as shown in FIG. 6B, and a ground line 63 and a second electrode terminal 73 as shown in FIG. Electrically connected.

  Further, the signal lines 62 and the ground lines 63 other than the terminal portions 68 of the flexible wiring board 600 are formed by covering a protective film 66 made of an insulating resin such as a resist.

  Other configurations are the same as those of the second embodiment shown in FIG.

  Below, the structure of the sheet-like device in the modification of the 2nd Embodiment of this invention is demonstrated using FIG.

  As shown in FIG. 7, the sheet-like device 69 includes, for example, a first electrode terminal 72 and a second electrode on a sheet-like substrate 120 such as polyimide or polyphenylene sulfide (for example, a thickness of 125 μm) with a dielectric film 170 interposed therebetween. The thin film capacitor 660 is provided with an electrode terminal 73. The sheet-like substrate 120 is preferably at least as large as the terminal portion 68 of the flexible wiring substrate 600. A plurality of thin film capacitors 660 are formed in, for example, an array according to the arrangement and number of the signal lines 62 and ground lines 63 of the flexible wiring board 600. Here, the first electrode terminal 72 of each thin film capacitor 660 is provided corresponding to the position of the signal line 62 alternately formed with the ground line 63 on the flexible wiring board 600, and is provided for each thin film capacitor 660. Connected to the electrode 180. The second electrode terminals 73 corresponding to the respective thin film capacitors 660 are provided corresponding to the positions of the ground lines 63 alternately formed with the signal lines 62 on the flexible wiring board 600, and the respective thin film capacitors 660 are shared. It connects with the upper layer electrode 190 to connect.

  The configuration of the sheet-like device other than the above is the same as that in the second embodiment, and the thin film capacitor of the sheet-like device can be formed in the same manner as in the first embodiment, and thus description thereof is omitted.

  With the above configuration, a flexible wiring board in which signal lines and ground lines are alternately formed can be obtained.

  Needless to say, the modification of the second embodiment of the present invention can be applied to the first embodiment.

  According to the modification of the second embodiment of the present invention, by forming the signal lines and the ground lines alternately on the base film, the signal lines are electromagnetically shielded by the adjacent ground lines. Crosstalk between signal lines can be suppressed. As a result, a flexible wiring board can be obtained in which the quality of the signal transmitted through the signal line is further improved.

  In each embodiment of the present invention, the sheet-like device has been described as an example in which thin film capacitors are formed in an array, but the present invention is not limited to this. For example, in the case of a thin film capacitor having a first electrode terminal and a second electrode terminal that can be connected corresponding to the ground line and signal line of the flexible wiring board, the shape pattern and arrangement of the upper layer electrode and the lower layer electrode are limited. Not. Moreover, the thin film capacitor in the sheet-like device may have a laminated structure.

  As a result, the capacitor capacity can be arbitrarily set in a wider range, and thus a flexible wiring board having further excellent electromagnetic noise prevention performance can be obtained.

  Moreover, in each embodiment of this invention, although the sheet-like device demonstrated in the example comprised by a thin film capacitor, it is not restricted to this. For example, a sheet-like device having various filter characteristics may be used as the sheet member by combining with the resistance and inductance of the thin film. Thereby, a flexible wiring board with further excellent reliability can be obtained.

  The flexible wiring board according to the present invention is useful as a flexible wiring board used for electronic devices and the like that are required to have high electromagnetic noise prevention performance.

(A) Perspective view for explaining a main part of the flexible wiring board according to the first embodiment of the present invention (b) AA line sectional view of FIG. 1 (a) (c) B- of FIG. 1 (a) B line cross section (A) Perspective plan view for explaining the configuration of the sheet-like device of the flexible wiring board in the first embodiment of the present invention (b) AA line sectional view of FIG. 2 (a) Electrical equivalent circuit diagram for explaining another example of the flexible wiring board in the first embodiment of the present invention (A) Perspective plan view for explaining the main part of the flexible wiring board according to the second embodiment of the present invention (b) AA line sectional view of FIG. 4 (a) (c) B of FIG. 4 (a) -B sectional view (A) Perspective plan view for explaining the configuration of the sheet-like device of the flexible wiring board in the second embodiment of the present invention (b) AA line sectional view of FIG. 5 (a) (A) Perspective plan view for explaining a main part in a modification of the flexible wiring board according to the second embodiment of the present invention (b) AA line sectional view of FIG. 6 (a) (c) FIG. 6 (a) BB line sectional view of (A) Perspective plan view for explaining the configuration of a sheet-like device in a modified example of the flexible wiring board according to the second embodiment of the present invention (b) AA line sectional view of FIG. 7 (a)

Explanation of symbols

1, 41, 61 Base film 2, 42, 62 Signal line 3, 43, 63 Ground line 4, 5 Land 6, 46, 66 Protective film 8, 48, 68 Terminal portion 9, 49, 69 Sheet-like device 10, 50 , 70 Sheet member 11 First conductive via 12 Second conductive via 22, 52, 72 First electrode terminal 23, 53, 73 Second electrode terminal 31, 32 Capacitor 44, 64 Tip 100, 400, 600 Flexible wiring board 110 Longitudinal direction 120 Sheet-like board 130 Short direction 160, 460, 660 Thin film capacitor 170 Dielectric film 180 Lower layer electrode 190 Upper layer electrode 200 Insulating protective film

Claims (6)

A base film in which a signal line and a ground line are formed on at least one surface;
A terminal portion having a sheet member on the other surface side of at least one end of the base film,
The flexible wiring board, wherein the sheet member is a sheet-like device in which a plurality of thin film capacitors connected to the signal line and the ground line are formed. A first electrode terminal of the thin film capacitor of the sheet-like device is connected to the ground line through a first conductive via provided in the base film, and a second electrode terminal of the thin film capacitor is connected to the base film. The flexible wiring board according to claim 1, wherein the flexible wiring board is connected to the signal line through a provided second conductive via. A base film in which a signal line and a ground line are formed on at least one surface;
At least one tip portion of the base film is folded, and includes a terminal portion having a sheet member on the folded surface of the tip portion,
The flexible wiring board, wherein the sheet member is a sheet-like device in which a plurality of thin film capacitors connected to the signal line and the ground line are formed. The first electrode terminal of the thin film capacitor of the sheet-like device is connected to the ground line, and the second electrode terminal of the thin film capacitor is connected to the signal line. Flexible wiring board. The sheet-like device is formed by forming the thin film capacitors having the first electrode terminal and the second electrode terminal in an array with a predetermined arrangement on one surface of a sheet-like substrate with a dielectric material interposed therebetween. The flexible wiring board according to any one of claims 1 to 4, wherein the flexible wiring board is provided. The flexible wiring board according to claim 1, wherein the signal lines and the ground lines are alternately arranged on the base film.

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