JPH095769A - Wiring connecting structure of electronic element - Google Patents

Abstract

PURPOSE: To prevent the intrusion of air by connecting materials and to improve reliability by thermally press bonding the connecting materials contg. conductive particles between the leader electrodes formed on the insulating substrate of an electronic element and the connecting terminals packed with insulating films therebetween. CONSTITUTION: This structure consists of a liquid crystal display element(LCD) 1 as the electronic element and a TCP 3 as the connecting element for connecting this LCD to external parts. The leader electrodes 12 are formed in the juncture 5 of one glass substrate 22 of the LCD 1. The insulating films 10 are packed between the plural connecting terminals 7 formed at flexible resin plate 6 of the TCP 3. An anisotropic conductive film 4 as the connecting material consisting of, for example, a thermosetting resin contg. conductive particles 13 is held between the leader electrodes 12 and the connecting terminals 7. The glass substrate 22 and the resin plate 6 are thermally press bonded in this state under heating. As a result, the transparent substrate 22 of the LCD 1 and the resin plate 6 of the TCP 3 are fixed to each other by the resin component of the anisotropic conductive film 4 and the leader electrodes 12 and the connecting terminals 7 are electrically connected to each other by the conductive particles 13.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to the connection of electronic devices,
In particular, it relates to a wiring connection structure using circuit wiring formed on a resin film.

[0002]

2. Description of the Related Art With the recent development of semiconductor processing technology, electronic devices manufactured by semiconductor technology have become smaller and more sophisticated, and various connection structures for connecting these devices have been developed. ing. Electronic parts such as liquid crystal display elements are so-called TCP (T) for the purpose of obtaining a three-dimensional or flexible connection arrangement when connecting to external parts that are electrically connected for the purpose of supplying electric signals.
a connection element called ape Carrier Package) and this TC
FPC with the same configuration as P but with no driving IC (FPC
Electrical connection is made using lexible-Printed Circuit).

As shown in FIG. 2, the TCP as such a connecting element is made of Cu on the surface of a flexible resin film 6.
It is composed of a circuit wiring (not shown) formed by patterning with a conductor such as a conductor and a driving IC 9 mounted on the circuit wiring. The circuit wiring is connected to the liquid crystal display element at both ends of the resin film 6. And a second electrode terminal 8 connected to an external component.

Using the TCP configured as described above,
As shown in FIG. 1, the liquid crystal display element 1 has a transparent substrate 2
_The lead electrode for external connection, which is drawn from the transparent electrode for liquid crystal control formed on the inner surface of the liquid crystal ₁ and 2 ₂ to the end 5 of the transparent substrate, is made of a resin containing conductive particles for the first electrode terminal 7 of the TCP 3. An electrical and mechanical connection is obtained by performing thermocompression bonding with a directional conductive film (ACF) 4 interposed. On the other hand, the second connection terminal 8 of the TCP3 is connected to the corresponding electrode of the external component by connecting means such as solder,
Thus, electrical and mechanical connection between the liquid crystal display element and external parts is obtained.

[0005]

In the conventional connection structure as described above, the first connection terminal 7 of the TCP 3 is parallel on the resin film 6 having a flat surface so as to correspond to the extraction electrode of the liquid crystal display element. It is formed into a shape. The first of these
The connection terminal 7 is generally formed to have a thickness of about 17 μm-35 μm in order to supply a required amount of power and prevent disconnection, so that the connection terminal protrudes from the surface of the resin film 6 by that thickness. It becomes a state.

Therefore, in the case where the ACF 4 is used to fix the glass substrate 2 ₂ of the liquid crystal display element 1 and the TCP 3 by thermocompression and to electrically connect the extraction electrode and the first connection terminal 7. , ACF 4 must be deformed according to the thickness of the first connecting terminals 7 to fill a part of the material between the patterns of these first connecting terminals in order to obtain such fixation. .

However, at the time of filling the ACF 4 between these patterns at the time of thermocompression bonding, external air is entrapped between the patterns, and the space between the ACF 4 and the resin film 6 of the TCP 3, especially the root portion of the first connection terminal 7. A so-called air pocket may be formed on the (resin film 6 side). The interposition of such air pockets causes the transparent substrate 2 ₁ ,
The fixing between 2 ₂ and the resin film 6 becomes unstable, and repeated temperature changes and stresses after connection may cause damage to the electrical connection between the extraction electrode and the connection terminal due to conductive particles. , The reliability of mechanical or electrical connection may be impaired.

Therefore, it is an object of the present invention to obtain a wiring connection structure for an electronic device, which improves the reliability of connection.

[0009]

According to the present invention, there is provided a wiring connection structure provided with a connection element interposed between an electronic element and an external component for connection, wherein the electronic element includes an insulating substrate and The plurality of extraction electrodes formed on the insulating substrate, the connection element has a resin film and a first connection terminal and a second connection terminal formed on the resin film so as to face each other, and between the first connection terminals. A wiring connection structure for an electronic element is provided, in which an electrically insulating insulating film is formed, and the extraction electrode and the first connection terminal are connected by a resin containing conductive particles.

[0010]

[Operation and effect] The wiring connection structure of the electronic element is thermocompression bonded between the extraction electrode formed on the insulating substrate of the electronic element, the electrode terminal filled with the insulating film, and the extraction electrode and the electrode terminal. Since the connection member includes conductive particles, the protrusion of the connection terminal in the height direction can be substantially reduced.

Therefore, even when the electrode terminal of the connection element is formed to have a cross-sectional shape or height that can supply a sufficient amount of electric power to the electronic element and is unlikely to cause disconnection,
The deformation of the connecting material during thermocompression bonding can be greatly reduced, and the possibility of air intervention by the connecting material can be greatly reduced. Therefore, it is possible to obtain a reliable mechanical and electrical connection between the electronic element and the connection element.

[0012]

EXAMPLE Next, regarding the connection wiring structure according to the present invention,
A liquid crystal display element as an electronic element and a TCP as a connection element will be described in detail according to an embodiment with reference to FIGS. 1 to 4. The wiring connection structure according to the present invention is shown in FIG.
As shown in, the liquid crystal display element (LC
D) 1 and a TCP3 as a connecting element for connecting the LCD 1 to an external part (not shown), and an anisotropic conductive film 4 which enables electrical connection between the both by thermocompression bonding through conductive particles. Connected through.

Although not described in detail, the LCD 1 has two transparent substrates 2 ₁ which sandwich the liquid crystal with a sealing material therebetween.
A transparent electrode formed on the 2 _second inner surface, and one of the glass substrates 2 _{and second} connecting portions 5 for connecting the transparent electrode to an external electrical components consists. As shown in a plan view in FIG. 2, the TCP 3 has a rectangular resin plate 6 made of a flexible resin and an edge side facing the surface of the resin plate 6 with a conductive material such as Cu. It is composed of a plurality of first connection terminals 7 and second connection terminals 8 formed respectively, and a driving IC 9 mounted on the resin plate 6. IC9 and first and second
The connection terminals 7 and 8 are electrically connected by circuit wiring (not shown).

The electrical connection between the extraction electrode of the LCD 1 and the first connection terminal 7 of the TCP 3 is, as described above, made of an anisotropic conductive film (a connecting material made of, for example, a thermosetting resin containing conductive particles). ACF) 4 is sandwiched between the _two, and the glass substrate ₂₂ and the resin plate 5 are thermocompression bonded by heating. The wiring connection structure of the present invention will be described in more detail. As shown in FIG.
An insulating film 10 made of an electrically insulating material, such as polyimide, is formed between the first connection terminals 7 on the resin plate 6 of No. 3 so as to fill the concave groove 11 defined between these terminals. . On the other hand, on the inner surface of the glass substrate 2 _{and second} end portions of LCD1 extraction electrodes 12 are formed. By thermocompression bonding via the ACF 4, the transparent substrate 2 ₂ of the LCD and the resin film of the TCP are fixed by the resin component of the ACF 4, and the lead electrode 12 of the former and the first electrode terminal 7 of the latter are fixed. It is electrically connected through the conductive particles 13 contained in the ACF 4.

The insulating film 10 can be formed in each groove 11 by using, for example, a photolithography technique applied to semiconductor manufacturing. As the material of the insulating film 10, a material that can obtain a certain adhesiveness to the material of the resin film 6, for example, polyimide is desirable.
As such a material, photosensitive polyimide or the like can be applied.

The insulating film 10 can be formed by applying a normal photolithography technique together with the formation of the first connection terminal 7 and the circuit wiring connected to them. That is,
As shown in FIG. 4A, Cu is formed on the surface of the resin film 6.
After applying a resist to a certain thickness on the surface of the flexible copper clad plate having the layer 7a formed thereon, the connection terminal 7 and the circuit wiring are formed in a desired pattern by photosensitization and etching treatment (FIG. 6B) (FIG. (C)). Then, a layer made of a photosensitive polyimide for forming an insulating film is formed in the region of the first connection terminal to have a layer thickness of, for example, 10 μm by a spin coating method or a printing method, and then the resist layer is removed.
The insulating film 10 is formed on the resin film between the connection terminals ((d) of the same figure).

As described in detail above, according to the wiring connection structure of the electronic element according to the manufacturing method of the present invention, the wiring connection structure of the electronic element has the extraction electrode formed on the insulating substrate of the electronic element and the insulating film. Since it is composed of an electrode terminal filled in between and a connecting material containing conductive particles thermocompression bonded between the extraction electrode and the electrode terminal, the protrusion of the connecting terminal in the height direction is substantially reduced. Can be made.

Therefore, even when the electrode terminals of the connection element are formed to have a cross-sectional shape or height capable of supplying a sufficient amount of electric power to the electronic element and less likely to cause disconnection,
The deformation of the connecting material during thermocompression bonding can be greatly reduced, and the possibility of air intervention by the connecting material can be greatly reduced. Therefore, the end of the transparent substrate of the LCD and the resin film of the TCP can be securely fixed without entrapment of air, and thus the reliability between the former extraction electrode and the first electrode terminal of the TCP can be improved. You can get a high connection.

Although the liquid crystal display element has been described as an example of the electronic element of the present invention in the above embodiment, the present invention is not limited to this, and a light emitting element or device using an LED or the like, It goes without saying that it can also be applied to other electronic components. Further, although the case where the TCP is used as the connection element has been described, the connection element may be applied to another flexible type such as the FPC.

[Brief description of drawings]

FIG. 1 is a side view showing a connection state between an LCD and a TCP.

FIG. 2 is a plan view of the TCP shown in FIG.

FIG. 3 is a partial cross-sectional view of a main part of the connection structure of the present invention.

FIG. 4 is a diagram showing a process of forming an insulating film according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal display element (LCD) 3 TCP 4 Anisotropic conductive film (a CF) 6 Resin film 7 1st electrode terminal 8 2nd electrode terminal 10 Insulating film 11 Recessed groove 12 Lead electrode 13 Conductive particle

Claims (1)

[Claims] 1. A wiring connection structure provided with a connection element interposed between an electronic element and an external component to be connected, wherein the electronic element is an insulating substrate and a plurality of electronic elements formed on the insulating substrate. The extraction electrode, the connection element is a resin film, and the first connection terminal and the second connection terminal are formed on the resin film so as to face each other.
A connection terminal, an electrically insulating insulating film is formed between the first connection terminals, and the extraction electrode and the first
A wiring connection structure for an electronic element, characterized in that the connection terminal is connected by a resin containing conductive particles.