JPH07326225A - Connection structure of anisotropic conductive material and electric circuit member - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an anisotropic conductive material for conductor connection, which can be easily manufactured at low cost and can cope with a narrow connection pitch without limitation. [Structure] The warp yarns 2 of conductive fibers and the warp yarns 3 of insulating fibers are alternately arranged, and the weft yarns 4 of insulating fibers are plain-woven to form the anisotropic conductive material 1. With this structure, it is easy to manufacture, can be obtained at a low cost, and the insulation in the lateral direction can be surely obtained to sufficiently reduce the pitch between the warp yarns 2 so that the connection conductor can be made narrower in pitch.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anisotropic conductive material effective as a connecting member when electrically connecting conductors arranged at a narrow pitch with high reliability, and an electric circuit member using the anisotropic conductive material. Regarding the structure.

[0002]

2. Description of the Related Art For example, in the case of terminal connection or intermediate connection of a tape electric wire, if a weak conductor is completely stripped and connected, the work becomes complicated and sufficient connection strength cannot be obtained. Is peeled off, the exposed conductor is reinforced by the coating left on the other surface, and the conductor is overlaid on the other conductor. In addition, if the conductors are connected to each other by direct soldering, it is difficult to obtain insulation reliability between adjacent conductors when minute conductors are arranged at a narrow pitch. Therefore, in such a case, An anisotropic conductive film is interposed between the connecting conductors.

A conventional example of the anisotropic conductive film is as follows.
(1) A part of a film is compressed to increase the density of conductive particles contained in the film at that part to obtain electrical conduction in the film thickness direction. (2) Japanese Patent Laid-Open No. 2-49385. As described above, a via hole is formed in the insulating film by photolithography or the like, and a plated conductor is embedded in the hole, (3) Japanese Patent Publication No. 3-53724, JP-A-4-121904, and JP-A-4-121905. And the like, there are those in which conductive fibers are penetrated in the insulating film in the film thickness direction by an electrostatic flocking method so as to be flocked.

[0004]

Among the above-mentioned conventional techniques, the anisotropic conductive film of (1) is easy to manufacture, but it is necessary to compress the portion for obtaining electrical conduction, and its application is narrow. Moreover, the electric resistance is large.

In the anisotropic conductive film (2), as shown in FIG. 4, a large number of via holes 8 are formed at predetermined positions in the insulating film 7, and then plated to fill the conductor 9 in the via holes. Since it is necessary, it takes time to manufacture and the cost is high. Furthermore, there is a lower limit to the via hole diameter because the conductor is plated and embedded, and it is difficult to further reduce the pitch between the holes.

Also in the anisotropic conductive film of (3), the electrode used for electrostatic flocking is patterned, or the adhesive layer for adhering the foot to be connected is patterned to limit the flocking area of the conductive fiber. In addition, since it is necessary to limit the electric conduction area, the manufacturing cost becomes high, and further, the restriction due to the patterning of the electrodes and the adhesive layer prevents further narrowing of the pitch.

Therefore, the present invention is to provide an anisotropic conductive material which is easy to manufacture and can meet the demand for further narrowing of the pitch of the electrical conducting portion, and an electrical circuit member connection structure using the anisotropic conductive material. It is an issue.

[0008]

In the anisotropic conductive material of the present invention for solving the above problems, first warp yarns made of conductive fibers and second warp yarns made of insulating fibers are alternately arranged. It is obtained by plain weaving different kinds of warp threads and weft threads made of insulating fibers. The warp threads and the weft threads may be monofilament threads.

The insulating fiber may be formed of a thermoplastic polymer material or may have a surface coated with a thermoplastic polymer material. If at least a part of the insulating fibers are such, a better anisotropic conductive material can be obtained, and it is also possible to omit the second warp yarn and reliably maintain the insulation in the lateral direction.

In the connection structure of the present invention, the above-mentioned plain weave anisotropic conductive materials are sandwiched between the interconnecting portions of the electric circuit members which are fixed to each other and fixed in parallel to each other at a predetermined pitch. Conductors are electrically connected to each other via conductive fibers of warp yarns. The anisotropic conductive material used in this connection structure is
As for the warp yarn restraining effect of the weft yarns, the warp yarns may be all made of conductive fibers and roughly woven.

[0011]

The anisotropic conductive material of the present invention can be obtained by simply plain-weaving the warp yarns and the weft yarns, so that it is excellent in productivity and can be obtained at a low cost.

Further, if only the warp yarns of the conductive fiber are densely woven, the insulation between the adjacent warp yarns becomes insufficient, and stable electrical connection cannot be expected. However, in the present invention, the first conductive fiber is used.
Since the second warp yarn of the insulating fiber is arranged between the warp yarns, the insulation between the conductive fibers is ensured and the short circuit does not occur.

Further, the conductive fiber has a small electric resistance, and the arrangement pitch of the conductive fiber can be made sufficiently small so that the connection pitch can be narrowed with a margin.
In the connection structure of the present invention, the characteristics of this anisotropic conductive material are sufficiently brought out, and a small size electric circuit member can be connected easily, inexpensively and with high reliability.

When at least the surface contains insulating fibers made of a polymeric material, the polymeric material is melted by heat treatment to adhere to the conductive fibers and restrain the conductive fibers after curing. Therefore, the stability of the conductive fiber in the stationary state is improved, and the reliability of the connection is more easily enhanced. Further, in this case, since the arrangement of the conductive fibers can be fixed by the weft yarn, the insulation in the lateral direction can be maintained even if the second warp yarn is omitted.

[0015]

EXAMPLE FIG. 1 shows an example of the anisotropic conductive material of the present invention. The anisotropic conductive material 1 is plain-woven by alternately arranging the warp yarns 2 of conductive fibers and the warp yarns 3 of insulating fibers and combining these with the weft yarns 4 of insulating fibers. The arrangement of the warp threads 2 and 3 and the weft thread 4 is roughened for the sake of clarity of the drawing, but can actually be made denser.

The warp yarn 2 of the conductive fiber may be made of metal such as copper, copper alloy, aluminum and aluminum alloy, or carbon. Further, the surface of the warp yarn 2 may be subjected to solder plating or the like.

As the warp yarn 3 and the weft yarn 4 of the insulating fiber, it is possible to appropriately select and use plant fiber such as hemp and cotton, glass fiber, synthetic fiber, monofilament of resin and the like.
In addition, all the yarns 3 and 4 or at least some of the weft yarns 4 are made of a thermoplastic polymer material, or have a surface coated with the thermoplastic polymer material and are heat treated after plain weaving to melt them. When (preferably only the surface layer portion is melted) and then cooled and hardened, the melted yarn adheres to the warp yarns 2 of the conductive fiber and the arrangement of the warp yarns 2 is fixed, and the conductive material is easy to use and reliable. To finish.

If the warp yarns are restrained by the weft yarns in this way,
As shown in FIG. 2, even when only the warp yarns 2 of the conductive fiber are roughly arranged, the lateral insulation can be maintained.

FIG. 3 shows an example in which the above-mentioned anisotropic conductive material 1 is used to make an intermediate connection between the tape wires 5 and 5. In the terminal connection, the conductor to be connected is changed to a terminal formed on the substrate or the like, but in any case, a plurality of these conductors are provided in parallel with the arrangement pitches matched. Therefore, as shown in the figure, the anisotropic conductive material 1 is applied between the opposing connecting portions and the warp yarn 2
Are oriented in the longitudinal direction of the conductor 6.
The arrangement pitch of the warp threads 2 is matched with the arrangement pitch of the conductors 6. Since the arrangement pitch of the warp yarns 2 can be made sufficiently small depending on the size of the fiber diameter, it is easy to match the pitch even if the arrangement pitch of the conductors 6 is small. The warp yarn 2 is arranged between all the conductors. The warp yarn 2 is corrugated in the thickness direction of the conductive material as shown in FIG. 1 (b) or FIG. 2 (b), and the valley portion of the wave is one conductor 6 and the mountain portion is the other conductor. Since the tape wires 5 and 5 are in contact with each other, by fixing the tape electric wires 5 and 5 to each other in the illustrated state, it is possible to achieve the purpose of electrical conduction while insulating laterally.

An appropriate clamp may be used to fix the tape wires to each other, but if the surface of the warp yarn 2 or the conductor 6 is plated with solder and the warp yarns are soldered or joined by ultrasonic welding. The work is easy and the contact resistance can be reduced.

[0021]

As described above, since the anisotropic conductive material of the present invention is formed by plain weaving conductive fibers and insulating fibers, it can be easily manufactured at low cost.

Further, both narrowing of pitch and reliable insulation in the lateral direction can be achieved, and connection restrictions can be eased.

Further, the connection structure of the present invention using this conductive material is excellent in workability and reliability, and can be expected to have a great effect particularly when collectively connecting a plurality of conductors arranged at a narrow pitch.

[Brief description of drawings]

FIG. 1A is a plan view showing an example of an anisotropic conductive material of the present invention. FIG. 1B is a cross-sectional view taken along line XX of the above.

FIG. 2 is a plan view of another embodiment.

FIG. 3A is a perspective view showing an example of a connection portion using the anisotropic conductive material of the present invention. FIG. 3B is a cross-sectional view of the same connection portion after assembly.

FIG. 4 is a perspective view showing a conventional example of an anisotropic conductive film.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Anisotropic conductive material 2 Warp yarn of conductive fiber 3 Warp yarn of insulating fiber 4 Weft yarn of insulating fiber 5 Tape electric wire 6 Conductor 7 Insulating film 8 Via hole 9 Conductor

Claims (5)

[Claims] 1. An anisotropic conductive material obtained by alternately arranging first warp yarns made of conductive fibers and second warp yarns made of insulating fibers, and plain weaving two kinds of warp yarns and weft yarns made of insulating fibers. Material. 2. The anisotropic conductive material according to claim 1, wherein at least a part of the insulating fibers is formed of a thermoplastic polymer material. 3. The anisotropic conductive material according to claim 1, wherein at least a part of the insulating fibers is covered with a thermoplastic polymer material. 4. A warp yarn of conductive fibers and a weft yarn of insulating fibers are plain-woven, and a warp yarn having at least a surface made of a thermoplastic polymer material is attached to the warp yarn to roughen the warp yarn array, and the warp yarn is fixed by the weft yarn. An anisotropic conductive material. 5. An interconnection in which a plurality of electric circuit members are overlapped with each other, and the anisotropic conductive material according to any one of claims 1 to 4 is provided between the overlapping surfaces so that the warp threads are oriented in the longitudinal direction of the conductor to be connected. And a connecting structure for electrically connecting each of the conductors arranged in parallel to each other at a predetermined pitch in the interconnecting portion through a warp of conductive fibers sandwiched between opposing conductors.