JPH05174890A - Joining structure - Google Patents

Abstract

PURPOSE:To accomplish a joining structure to join surely electrode terminals of a fine pitch provided oppositely each other. CONSTITUTION:An electrode terminal 4 of a liquid crystal display panel 1, and an electrode terminal 7 of a semiconductor unit 2 are provided oppositely each other, and an anisotropic connector 12 in which metallic particles 10 are dispersed and mixed in an insulating adhesive 9 is placed between the electrode terminals 4 and 7. The electrode terminal 7 of the semiconductor unit 2 is covered by an insulating membrane 11 of a thermal hardening property along the whole surface. The insulating membrane 11 is broken through by the metallic particles 10 in a thermocompression bonding, and thereby, the electrode terminals 4 and 7 are communicated through the metallic particles 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joining structure for joining one electrode terminal and the other electrode terminal formed on a pair of substrates.

[0002]

2. Description of the Related Art Conventionally, for example, a liquid crystal display device shown in FIG. 4 has been known as a display device for displaying information such as characters, figures and images. This liquid crystal display device has a liquid crystal display panel 1.
The semiconductor unit 2 is bonded to the semiconductor unit 2 and the liquid crystal display panel 1 is driven by this semiconductor unit 2 to display required information. The liquid crystal display panel 1 includes a pair of upper and lower transparent glass substrates 3
A transparent electrode made of ITO (Indium Tin Oxide) or the like is formed on the opposing surfaces of a and 3b, liquid crystal is enclosed between them, and each end of the transparent glass substrates 3a and 3b is projected laterally. A large number of electrode terminals 4 for connection are formed on. The semiconductor unit 2 has a flexible film substrate 5 made of polyimide or the like on which a semiconductor chip 6 such as an IC or LSI is mounted, and a large number of electrode terminals 7 for connection are patterned on the periphery of the film substrate 5. There is. The liquid crystal display panel 1 and the semiconductor unit 2 are shown in FIG.
It is joined as shown in. That is, the electrode terminal 7 formed on the film substrate 5 and the electrode terminal 4 formed on the transparent glass substrate 3b are opposed to each other so as to overlap with each other, and the anisotropic connector 8 is interposed therebetween to join them. ..
The anisotropic connector 8 is made by mixing an insulating adhesive 9 with metal particles 10. Therefore, at the time of bonding, the metal particles 10 are sandwiched between the opposing electrode ends 4 and 7, and the opposing electrode terminals 4 and 7 are conducted through the metal particles 10, but the adjacent electrode terminals 4 There is no conduction between 4 and 7 and 7, and the insulating property is maintained.

[0003]

However, in the joint structure as described above, in order to deal with fine pitch (fine density) of the adjacent electrode terminals 7, 7 and 4, 4, the anisotropic connector is used. When the number of the metal particles 10 of 8 is increased, the electrical conductivity between the opposing electrode terminals 7 and 4 is maintained, but the insulating property between the adjacent electrode terminals 7, 7 and 4, 4 deteriorates, and conversely. , When the number of metal particles 10 is reduced,
The insulating property between the adjacent electrode terminals 7, 7 and 4, 4 is improved, but the electrical conductivity between the opposing electrode terminals 7 and 4 is deteriorated. Therefore, such a joint structure has a drawback that it is difficult to make the adjacent electrode terminals 7, 7 and 4, 4 fine pitched. The present invention has been made in view of the above-mentioned circumstances, and a purpose of the present invention is to provide a joint that can reliably and satisfactorily conduct electrical conduction between electrode terminals that face each other and that enables fine pitch of the electrode terminals. To provide the structure.

[0004]

According to a first aspect of the present invention, an anisotropic connector formed by mixing conductive particles in a heat-melting type insulating adhesive is interposed between electrode terminals arranged opposite to each other. In the joining structure for joining by joining, the surface of at least one of the electrode terminals is covered with an insulating coating, and the conductive particles of the anisotropic connector break through the insulating coating during thermocompression bonding to electrically connect the electrode terminals. And According to a second aspect of the present invention, there is provided a joint structure in which an anisotropic connector formed by mixing conductive particles into a heat-melting type insulating adhesive is interposed between electrode terminals arranged opposite to each other, and is joined.
The entire surface of the conductive particles is covered with an oxide insulating film, and the oxide insulating film is broken during thermocompression bonding so that the electrode terminals are electrically connected by the conductive particles. According to a third aspect of the present invention, there is provided a joint structure in which an anisotropic connector formed by mixing conductive particles in a heat-melting type insulating adhesive is interposed between electrode terminals arranged to face each other and is joined. The entire surface of the conductive particles is covered with an insulating coating made of a material containing a thermoplastic resin, the insulating coating is broken during thermocompression bonding, and the electrode terminals are electrically connected by the conductive particles.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. Members having the same configurations and functions as the members shown in FIGS. 4 and 5 shown in the section of the prior art are denoted by the same reference numerals, and duplicate description is omitted.

The electrode terminal 4 of the liquid crystal display panel 1 is made of ITO or the like as in the above-mentioned conventional example, and is formed to be extremely thin.

The electrode terminal 7 of the semiconductor unit 2 is formed by etching copper foil or the like, and the thickness thereof is much thicker than that of the electrode terminal 4 of the liquid crystal display panel 1 described above. An insulating coating 11 of thermosetting epoxy resin or the like is formed to a thickness of about 10 μm by a dip method or the like.

Further, the anisotropic connector 12 interposed between the electrode terminals 4 and 7 mixes hard metal particles 10 made of Ni or the like having a diameter larger than the thickness of the insulating coating 11 into the adhesive 9 having an insulating property. It was done. The electrode terminals 7 and 4 are joined by thermocompression bonding via the anisotropic connector 12 therebetween.

Thus, when the electrode terminals 4, 7 are joined by thermocompression bonding, the hard metal particles 10 sandwiched between the electrode terminals 4, 7 pierce the insulating coating 11 on the surface of the electrode terminal 7, and 7 are pressed against each other to electrically connect the electrode terminals 4 and 7. On the other hand, between the adjacent electrode terminals 7, 7, since the metal particles 10 do not break through the insulating coating film 11 on the side surface of the electrode terminal 7 during thermocompression bonding, between the adjacent electrode terminals 7, 7, Even if the metal particles 10 are in contact with each other and the metal particles 10 are electrically connected to each other, the insulating property between the adjacent electrode terminals 7 is ensured. Therefore, the fine pitch of the electrode terminals 4 and 7 can be achieved.
In this case, since the electrode terminals 4 of the liquid crystal display panel 1 are extremely thin, the metal particles 10 of the anisotropic connector 12 are
Therefore, the adjacent electrode terminals 4 and 4 do not become conductive, but when the thickness of the electrode terminals 4 and 4 increases,
An insulating coating may be applied to this surface similarly to the electrode terminal 7 of the semiconductor unit 2 described above.

Next, a second embodiment of the present invention will be described with reference to FIG. In the drawings, members having the same configuration and action are denoted by the same reference numerals, and duplicate description is omitted. In this embodiment, the anisotropic connector 13 has an insulating adhesive 9
And the metal particles 10 having the surface coated with the insulating coating 14 mixed in the adhesive 9.

The metal particles 10 are solder particles, and the surface of the metal particles 10 is an insulating film 14 made of an oxide film.
Has been applied.

Then, thin transparent flux (surfactant) is applied to the upper surface of the transparent glass substrate 3b and the surface of the electrode terminal 4 formed on the upper surface, and the film substrate 5 and the electrode terminal 7 formed on the rear surface thereof. Are aligned through an adhesive 9 mixed with metal particles 10 coated with an insulating coating 14, and the upper surface of the film substrate 5 is pressed by a heater chip, whereby the electrode terminals 4 of the transparent glass substrate 3b and the film substrate 5 are aligned. And the electrode terminal 7 of are joined.

Thus, between the opposing electrode terminals 4 and 7, the insulating coating 14 made of an oxide coating is broken by the effect of temperature and flux, and the metal particles 10 contact the electrode terminals 4 and 7 and melt. Then, the electrode terminals 4 and 7 are electrically connected. On the other hand, between the adjacent electrode terminals 4 and 7, since the insulating coating 14 is not broken during thermocompression bonding, the insulating property can be secured.

Therefore, there is an effect that the fine pitch of the electrode terminals 4 and 7 can be achieved. The insulating coating 14 made of thermoplastic resin or the like may be formed on the surface of the metal particles 10 by a dipping method or the like.

[0015]

As described in detail above, the first to third aspects are described.
According to the invention described in 3, between the pair of opposing electrode terminals formed on the pair of substrates, the pair of opposing electrode terminals can be surely and satisfactorily energized, and between the adjacent electrode terminals, Further, there is an effect that it is possible to surely prevent conduction between them, and thereby to make the pitch of the electrode terminals finer.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of an electrode terminal portion of a semiconductor unit.

FIG. 3 is a vertical sectional view of a second embodiment.

FIG. 4 is a plan view of a conventional joining structure.

FIG. 5 is a vertical sectional view of the joint portion.

[Explanation of symbols]

 3b, 5 substrate 4, 7 electrode terminal 8, 12, 13 anisotropic connector 9 adhesive 10 metal particle (conductive particle) 11, 14 insulating film

Claims (3)

[Claims] 1. A joint structure in which an anisotropic connector made by mixing conductive particles in a heat-melting type insulating adhesive is interposed between electrode terminals arranged opposite to each other, and at least one of the electrodes is provided. A bonding structure in which the surface of the terminal is covered with an insulating coating, and the conductive particles of the anisotropic connector penetrate through the insulating coating during thermocompression bonding to conduct the electrode terminal. 2. A joint structure in which an anisotropic connector made by mixing conductive particles in a heat-melting type insulating adhesive is interposed between opposed electrode terminals to be bonded, and the surface of the conductive particles is provided. A joint structure characterized in that the whole is covered with an oxide insulating coating, and the oxide insulating coating is broken during thermocompression bonding so that the electrode terminals are conducted by the conductive particles. 3. A bonding structure in which an anisotropic connector made by mixing conductive particles in a heat-melting type insulating adhesive is interposed between electrode terminals arranged opposite to each other and bonded, the surface of the conductive particles. A joint structure characterized in that the whole is covered with an insulating coating made of a material containing a thermoplastic resin, and the insulating coating is broken during thermocompression bonding so that the electrode terminals are conducted by the conductive particles.