JP2000315059A - Tcp-type semiconductor device and method for connecting the device with liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the fear of short circuit caused by foreign matters, to eliminate the requirement for accuracy of alignment for connections, to increase reliability of the connections, and also to reduce the processing costs therefor. SOLUTION: Plural conductor patterns 5 are formed on an insulating base film 1 with a predetermined hole formed therein, and these conductor patterns 5 form an inner lead part 3 and an outer lead parts 2a, 2b. An IC chip is connected with the inner lead part 3, and the conductor patterns 5 are coated with a covering ink 8. The covering ink 8 is formed of a thermo-plastic resin having plasticity at the pressure bonding temperature at the time of pressure- bonding the outer lead parts 2a, 2b to electrodes of an LCD panel 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to TCP (Tape Carri
The present invention relates to a method of connecting a semiconductor device to a liquid crystal display device by connecting a semiconductor chip as a liquid crystal driving circuit by connecting the semiconductor device to a liquid crystal panel electrode of the liquid crystal display device.

[0002]

2. Description of the Related Art When connecting a TCP type semiconductor device to an LCD (liquid crystal) panel, it is important to connect a large number of electrodes arranged at a narrow pitch of the LCD panel reliably and with high reliability. For this purpose, an electrode of a TCP type semiconductor element and an electrode of an LCD panel are usually connected to each other using a method called pressure welding using an anisotropic conductive film. In this case, the conductive pattern of the TCP type semiconductor element which is not related to the pressure contact is covered with a solder resist (cover ink) so as not to be exposed.

However, according to this method, if the cover ink 8 of the TCP type semiconductor element is covered beyond the end face of the electrode substrate 11 of the LCD panel 10 to the vicinity of the press contact portion as shown in FIG. Since the conductive particles included in the cover 21 are blocked by the cover ink 8, the particles easily aggregate at the interface with the cover ink.
Further, the thickness of the cover ink 8 is set to
Therefore, when the thickness is larger than the thickness at the time of final press connection, the thickness of the press contact portion is determined by the thickness of the cover ink 8, and a difference in thickness occurs between the press contact portion and the cover ink 8. As a result, a stress in the peeling direction is applied to the press contact portion.

On the other hand, as shown in FIG.
The above problem does not occur when the substrate does not reach the end surface of the electrode substrate 11 of the LCD panel 10, but a portion short to the substrate end surface has a shape in which the conductive pattern 5 is exposed, and there is a possibility of a short circuit due to conductive foreign matter. There was no reliable pressure welding connection.

Therefore, as a countermeasure, the cover ink 8 is stopped just before the end face of the electrode substrate 11 of the LCD panel 10 to solve the above-mentioned problems of aggregation and stress, and as a countermeasure against the exposure of the conductive pattern, after press-contact. The exposed portion is coated with a resin film 9.
However, this method is not sufficient in terms of production cost and production capacity, such as the need for man-hours for resin coating and time for resin drying.

Therefore, for example, Japanese Patent Application Laid-Open No. 6-235928
In the publication, although there is a difference between the flexible conductive member and the TCP type semiconductor element, the flexible conductive member is equivalent to an anisotropic conductive film and is made of a material which is cured by heating under pressure,
A second adhesive covering the transparent electrode and the conductor pattern;
A liquid crystal display device comprising a thermoplastic resin and having a first adhesive covering a transparent electrode and a conductive pattern near an end face of a flexible conductive member and an end face of a liquid crystal display (LCD) panel is disclosed. Have been.
In this liquid crystal display device, the first adhesive softens and flows by pressurizing and heating, and goes out from the end face to cover the exposed portions of the transparent electrode and the conductor pattern. For this reason,
No short circuit due to conductive foreign matter occurs.

However, Japanese Patent Application Laid-Open No. 6-235928 discloses
Since the first and second adhesives are used, a new problem occurs when these adhesives are applied to the flexible conductive member and the liquid crystal display panel or applied by any method. That is, when the first and second adhesives are simultaneously applied, an apparatus for applying two types of adhesives or 2
It is necessary to prepare an adhesive material that integrates various types of adhesives, and when these first and second adhesives are separately applied, the man-hours required for applying each adhesive and each adhesive There is a problem that it becomes necessary to consider the positional accuracy of applying the agent.

The present invention has been made in view of the above-mentioned problems, and there is no risk of short-circuiting due to foreign matters, no need for alignment accuracy at the time of connection, high reliability of connection, and It is an object of the present invention to provide a TCP type semiconductor device having a low processing cost and a method for connecting the same to a liquid crystal display device.

[0009]

A TCP type semiconductor device according to the present invention comprises an insulating base film having predetermined holes, a plurality of conductive patterns formed on the base film, and a conductive pattern formed on the base film. The inner lead portion and the outer lead portion provided as a part, the IC chip connected to the inner lead portion, and the plasticity at the pressing temperature at the time of pressing the outer lead portion formed on the conductor pattern to the connection target by pressing. And a protective film made of a thermoplastic resin having the following.

According to a method of connecting a TCP type semiconductor device to a liquid crystal display device according to the present invention, there is provided an electrode substrate, a liquid crystal panel electrode formed on the electrode substrate, and the electrode substrate sandwiched by the liquid crystal panel electrode. In a method for connecting a TCP type semiconductor element to a liquid crystal panel having a counter substrate disposed so as to face the TCP type semiconductor element, the TCP type semiconductor element comprises:
An insulating base film having a predetermined hole, a plurality of conductor patterns formed on the base film, an inner lead portion and an outer lead portion provided as a part of the conductor pattern, and the inner lead portion. A connected IC chip, and a protective film made of a thermoplastic resin formed on the conductor pattern and having plasticity at a press-contact temperature when the outer lead portion is connected to a connection target by press-bonding. Coating is performed beyond a position corresponding to an end face of the electrode substrate, an anisotropic conductive film is interposed between the outer lead portion and the liquid crystal panel electrode, and the outer lead portion is pressed at a predetermined pressing temperature. The outer lead portion and the liquid crystal panel electrode are pressed by the anisotropic conductive film by pressing toward the liquid crystal panel electrode. Characterized in that it connects.

According to the present invention, in the TCP type semiconductor device, the whole of a protective film called a solder resist formed for the purpose of protecting electrodes and wiring layers or a portion near a press-contact portion is made of a thermoplastic material. Have been. Therefore, the temperature and pressure are applied to the anisotropic conductive film to make the LCD
When thermocompression bonding is performed between the electrode and the conductor pattern, the protective film is fluidized and covers the conductor pattern, and the occurrence of the exposed portion can be prevented.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a bottom view showing a TCP type semiconductor device according to an embodiment of the present invention, and FIG. 2 is a sectional view showing connection between the TCP type semiconductor device and an LCD panel.

In an LCD panel 10 of a liquid crystal display device, a liquid crystal panel electrode 12 is formed on an electrode substrate 11, and a counter substrate 13 faces the electrode substrate 11 with the liquid crystal panel electrode 12 interposed therebetween. Are located in
The opposing substrate 13 is joined to the electrode substrate 11.

In the TCP type semiconductor element 20, a conductor pattern 5 is formed on a base film 1 which is an insulator formed by punching holes in a predetermined shape. This conductor pattern 5
Is the LCD panel 1 to which the TCP type semiconductor element 20 is connected.
Outer lead 2 connected to the liquid crystal panel electrode 12
a, an outer lead portion 2b for connection to the outside,
And an inner lead portion 3 connected to the C chip 4.
The IC chip 4 is mounted on the inner lead portion 3, and each electrode of the IC chip 4 is connected to each conductor pattern of the inner lead portion 3. The conductor pattern 5 on the base film 1 has a cover called a solder resist made of a thermoplastic resin except for the outer lead portion 2a connected to the LCD electrode 12 and the outer lead portion 2b connected to the outside. It is covered with ink 8 (protective film). The cover ink 8 is coated beyond the position corresponding to the end face of the electrode substrate 11 in consideration of the dimensional tolerance of the electrode substrate 11, the bonding accuracy between the TCP type semiconductor element 20 and the LCD panel 10, and the like.

When the TCP type semiconductor device thus configured is connected to the LCD panel 10, as shown in FIG. 2, the TCP type semiconductor device 20 of this embodiment is connected to the LCD panel 10 by the outer lead portion 2a. 10 so as to be aligned with the liquid crystal panel electrode 12, and the outer lead portion 2.
a between the liquid crystal panel electrode 12 and the liquid crystal panel electrode 12
1 is interposed. Then, the LCD electrode 12 and the outer lead portion 2a are pressed against each other by pressing the anisotropic conductive film 21 under heating. In this case, since the cover ink 8 of this embodiment is made of a thermoplastic resin having plasticity at this pressing temperature, the cover ink 8 flows and the conductive pattern 5 not covered with the anisotropic conductive film 21 is formed. No exposed portion is generated in the conductor pattern 5 after the connection. For this reason, as shown in FIG. 4, it is not necessary to coat this portion with the resin film 9 after the pressure welding as a conventional countermeasure for preventing the conductive pattern from being exposed. Becomes unnecessary.

Further, in this embodiment, since the cover ink 8 is made of a thermoplastic resin, the peeling stress on the press contact portion can be reduced. That is, as shown in FIG. 3 showing the prior art, when the cover ink 8 of the non-thermoplastic TCP type semiconductor element is covered beyond the end face of the electrode substrate 11 of the LCD panel 10 to the vicinity of the press contact portion, the anisotropic conductive property is obtained. The conductive particles contained in the film are covered with the cover ink 8.
Particles are easily aggregated at the interface with the cover ink. When the thickness of the cover ink is thicker than the thickness when the cover ink is finally press-connected by the anisotropic conductive film, the thickness of the press-contact portion is determined by the thickness of the cover ink. When a difference in thickness occurs in the ink portion, a stress in the peeling direction is applied to the press contact portion. On the other hand, in the present invention, since the cover ink is thermoplastic, it does not block the conductive particles of the anisotropic conductive film 21 due to softening and fluidization at the time of pressing, Since the pressure-contact thickness determined by the anisotropic conductive film 21 is obtained, the difference in thickness between the pressure-contact portion and the cover ink 8 can be eliminated, so that the peeling stress can be reduced.

Further, in this embodiment, since there is no aggregation of particles at the interface, it is not necessary to stop the cover ink just before the end face of the electrode substrate 11 of the LCD panel.
Since it is not necessary to coat with the resin film 9 in order to prevent the conductor pattern from being exposed, the man-hour for resin coating and the time for drying the resin become unnecessary. Therefore, in this embodiment, the manufacturing cost is low and the manufacturing capacity is high.

The anisotropic conductive film 21 may be provided on the side of the TCP type semiconductor element 20 or the LCD panel 10.
It may be provided on the side.

The cover ink 8 of the TCP type semiconductor element 2 not only protects the conductor pattern 5 which is the first object, but also has an anisotropic property because of its thermoplasticity, the viscosity of which decreases during pressure welding. The portion exceeding the thickness of the portion connected by the conductive film 21 flows out of the gap between the cover ink 8 and the anisotropic conductive film 21 due to the pressure of the pressing. For this reason, it is not necessary to consider the distortion of the base film 1 caused by the difference in thickness between the anisotropic conductive film 21 and the cover ink 8 and the decrease in the adhesive force caused by the distortion. In addition, since the cover ink 8 can be coated in one process, the number of man-hours does not increase unlike the related art. Furthermore, since the coating position of the cover ink can be formed with the positional accuracy of the TCP type semiconductor device, the positional accuracy can be improved with the LCD panel connected in alignment with the TCP type semiconductor device, and the position of the anisotropic conductive film can be improved. The advantage is obtained that it is relatively independent of positional accuracy.

Further, in the conventional techniques described in JP-A-8-234222 and JP-A-6-235928, a material is transferred side by side to a base film. For this reason, it is necessary to introduce equipment for transferring such materials side by side, but in the present embodiment, there is no need to transfer these materials side by side, and the existing ones that have been used for a long time are simply used. The connection can be made using a transfer device for the cover ink and a transfer device for the anisotropic conductive film. Therefore, there is no need for new capital investment for connection.

Further, conventionally, since different materials are transferred adjacent to each other, accuracy of alignment between them is required. However, in the present embodiment, only the transfer accuracy between the LCD panel and the anisotropic conductive film needs to be considered. In addition to the transfer accuracy between the LCD panel and the anisotropic conductive film, the TCP There is no need for precision in alignment between the die semiconductor device and the adhesive (resin film). In other words, in contrast to the conventional TCP-type semiconductor element, the positioning of the three members between the anisotropic conductive film and the adhesive (resin film) was required, in the present embodiment, the TCP-type semiconductor element Positioning of the two members with the anisotropic conductive film is sufficient, and the connection work becomes extremely easy.

[0022]

As described above, according to the present invention,
The conventional TCP type semiconductor device cover ink generating device and anisotropic conductive film forming device are used as they are,
The semiconductor device and the LCD panel can be connected. Further, according to the present invention, since the cover ink and the anisotropic conductive film are formed in separate steps, the cover ink can be controlled by its formation error. As in the case of the related art, it is not necessary to consider the positional accuracy of two types of adhesives as in the related art.

[Brief description of the drawings]

FIG. 1 is a bottom view showing a TCP type semiconductor device according to an embodiment of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a cross-sectional view showing a connection state between a conventional semiconductor element and a liquid crystal display device.

FIG. 4 is a cross-sectional view showing a connection state between another conventional semiconductor element and a liquid crystal display device.

[Explanation of symbols]

 1: Base film 2a, 2b: Outer lead part 3: Inner lead part 4: IC chip 5: Conductor pattern 8: Cover ink 9: Resin film 10: LCD panel 11: Electrode substrate 12: Liquid crystal panel electrode 20: TCP type semiconductor Element 21: Anisotropic conductive film

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H092 GA40 GA49 MA32 MA34 NA16 NA27 5C094 AA42 AA43 AA44 BA43 DA15 DB02 GB01 5E319 AA03 AB03 BB12 BB16 CC61 5F044 MM03 MM13 MM26 MM44 NN01 NN13 NN19

Claims (2)

[Claims] An insulating base film having predetermined holes, a plurality of conductor patterns formed on the base film, an inner lead portion and an outer lead portion provided as a part of the conductor pattern; An IC chip connected to the inner lead portion, and a protective film made of a thermoplastic resin formed on the conductor pattern and having plasticity at a press-contact temperature when the outer lead portion is connected to a connection target by press-contact. A TCP type semiconductor device characterized by the above-mentioned. 2. A liquid crystal panel comprising: an electrode substrate; a liquid crystal panel electrode formed on the electrode substrate; and a counter substrate disposed to face the electrode substrate with the liquid crystal panel electrode interposed therebetween. On the other hand, in the method of connecting a TCP-type semiconductor element, the TCP-type semiconductor element includes an insulating base film having a predetermined hole, a plurality of conductor patterns formed on the base film, An inner lead portion and an outer lead portion provided as a part, and an IC connected to the inner lead portion
A protective film made of a thermoplastic resin formed on the conductor pattern and having plasticity at a press-contact temperature when the outer lead portion is connected to a connection target by press-contact, and the protective film is formed of the electrode substrate. The outer lead portion and the liquid crystal panel electrode are sandwiched between the outer lead portion and the liquid crystal panel electrode, and the outer lead portion is coated on the liquid crystal panel electrode at a predetermined pressure contact temperature. A method of connecting a TCP-type semiconductor element to a liquid crystal display device, wherein the outer lead portion and the liquid crystal panel electrode are connected by the anisotropic conductive film by pressing the liquid crystal display device.