JP2000194001A - Method for manufacturing electric circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent corrosion, disconnection, etc., of information electrodes. SOLUTION: Information electrodes 2 and connection terminals 4 are formed on a surface of a glass substrate 3, and an insulating film 5 is formed so that the information electrodes 2 are coated with it but the connection terminals 4 are exposed, however, before the insulating film 5 is formed, a resist film (unshown in the figure) is formed on the part of the connection terminals 4, and after the insulating film 5 has been formed so as to cover the information electrodes 2 and the resist film, the insulating film on the part of the connection terminals 4 are removed together with the resist film. Thus, it is possible to coat the information electrodes 2 with the insulating film 5 and expose the connection terminals 4. As the result, it is possible to reduce foreign matters sticking to the information electrodes 2, and prevent corrosion, disconnection, etc., of the information electrodes 2 incident to the adhesion of the foreign matters.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electric circuit device in which electrodes formed on two substrates are electrically connected.

[0002]

2. Description of the Related Art Conventionally, an electrode and a coating film for coating the electrode are formed on the surface of a base material, and only the connection terminals of the electrodes are exposed from the coating film. An electric circuit device that electrically connects other base materials,
It is used for various devices.

In such an electric circuit device, it is necessary to form the coating film so as to cover only the electrodes and not to cover the connection terminals. The method of masking the connection terminal portion has been used.

Hereinafter, this point will be described with reference to FIG. 5 taking a liquid crystal device as an example.

FIG. 5 is a diagram for explaining a conventional structure of a liquid crystal device as an example of such an electric circuit device.
The illustrated liquid crystal device 30 includes a glass substrate 3 as a constituent member of the liquid crystal panel P. On the surface of the glass substrate 3, a large number of information electrodes 32 and their connection terminals 34 are formed. Further, the liquid crystal device 30 includes a TAB film 36 on the surface of which a number of electrodes are formed.
The electrode on the film side and the connection terminal 34 are electrically connected.

Incidentally, the information electrode 32 is formed on the insulating film 3.
5 or an orientation film (not shown) is generally used, but only the connection terminals 34 need to be exposed for connection with the TAB film 36.

Therefore, when the insulating film 35 is formed on the glass substrate 3 on which the information electrodes 32 and the connection terminals 34 are formed by sputtering, only the connection terminals 34 are masked.
5 was not covered.

Reference numeral 6 denotes a driving IC mounted on the TAB film 36. The driving IC 6 is mounted on the TAB film 36. As another method, as shown in FIG. There is a COG (Chip On Glass) method in which the driving IC 6 is directly mounted on the glass substrate 3.

The same parts as those shown in FIG. 1 are denoted by the same reference numerals, and the description is omitted.

[0010]

However, in the method using masking as described above, it is difficult to control the accuracy, and a relatively large area is exposed.

For this reason, although there is no particular problem in an electric circuit device in which the region where the connection terminal is formed is relatively large, in a display device such as a liquid crystal device where the region is fine, not only the connection terminal 34 but also the electrode A large area including 32 is exposed. As a result, foreign matter easily adheres to the exposed portion of the electrode 32. * Corrosion or disconnection of the electrode 32 due to the adhesion of the foreign matter occurs, thereby impairing the reliability of the electric circuit device itself. In the case where foreign matter adheres between the electrodes 32, they are conducted. (The occurrence of such conduction is remarkable when the electrode pitch is reduced, for example, when high definition is to be achieved in a liquid crystal device.) is there),
was there.

For this reason, the electric circuit device to which foreign matter has adhered is removed by inspection, which is generally performed, but there is a problem that the manufacturing yield is reduced accordingly.

As a method of exposing the connection terminals 34 from the coating film 35, a method of applying the coating film 35 only to a necessary area by a printing method is conceivable. Therefore, there was a similar problem.

Accordingly, an object of the present invention is to provide a method of manufacturing an electric circuit device for preventing corrosion and disconnection of an electrode.

Another object of the present invention is to provide a method of manufacturing an electric circuit device for preventing conduction between electrodes.

Another object of the present invention is to provide a method of manufacturing an electric circuit device which prevents a reduction in manufacturing yield.

[0017]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a plurality of first base materials are provided on the surface of a first base material.
Forming an electrode or a connection terminal of the first electrode; forming a coating film so as to cover the first electrode and expose the connection terminal; and forming a coating film on the exposed connection terminal. Electrically connecting the second electrode formed on the two bases, the method for manufacturing an electric circuit device, comprising: after forming the first electrode and the connection terminal, covering both of them. Forming a coating film; and patterning the coating film so that the connection terminals are exposed.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
An embodiment of the present invention will be described.

As shown in FIGS. 1 (a) and 1 (b), an electric circuit device 1 manufactured according to the present invention includes a first base material 3 having a plurality of first electrodes 2 formed on a surface thereof. And the first base material 3
A plurality of connection terminals 4 are formed on the surface of the first electrode 2 so as to be electrically connected to the first electrodes 2. Further, a coating film 5 is formed on the surface of the first base material 3.
Are arranged so as to cover the first electrode 2 and to expose the connection terminal 4 without coating. Further, the electric circuit device 1 includes a second base member 6 on which a plurality of second electrodes (not shown) are formed, and the second electrodes and the connection terminals 4 are electrically connected. . The connection may be made by the ACF 7.

Although the present invention can be applied to any electric circuit device as long as it has the above-described configuration, it is preferable to apply it to a display device such as a liquid crystal device, and FIG. FIG. 2 is a plan view showing a structure of a liquid crystal device as one embodiment of the electric circuit device, and FIG. 2B is a cross-sectional view taken along line AA of FIG. The illustrated liquid crystal device 1 includes a pair of substrates 10 and 3.
And a liquid crystal element P having a liquid crystal 11 interposed therebetween. At least one substrate 3 corresponding to the first base material has a plurality of electrodes (first electrodes) 2 and The connection terminal 4 is formed. On the surface of the substrate 3, an insulating film 5 as a coating film is formed in the above-described shape.

Here, as the second base material when the present invention is applied to a liquid crystal device, a drive signal applied to the liquid crystal element P as indicated by reference numeral 6 in FIGS. 1 (a) and (b) IC for generating an image
And * a flexible T as indicated by reference numeral 36 in FIG. 1 (b).
An AB film on which the driving IC 6 is mounted can be cited.

When the present invention is applied to a liquid crystal device, the insulating film 5 is preferably transparent, and for example, a metal oxide film can be used.

Further, a transparent electrode such as ITO (indium tin oxide) may be used for the electrode 2,
A metal electrode for reducing the electrode resistance may be formed between the electrode 2 and the insulating film 5.

Here, the metal electrode has a three-layer structure. For example, the first layer and the third layer are made of Ta-Mo having a thickness of 400 °.
An alloy (Ta; 9% wt, Mo; 91% wt) was formed, and the second layer at the center was made of Al-Si-
It may be formed of a Cu alloy layer (Si; 1% wt, Cu: 0.5% wt). The metal electrode may be formed by a sputtering method and a photolithography method.

Next, a method of manufacturing the electric circuit device 1 according to the present invention will be described with reference to FIGS.

In manufacturing the electric circuit device 1, first, a plurality of first electrodes 2 and connection terminals 4 are formed on the surface of the first base material 3 (see FIG. 2B).

Next, the first electrode 2 and the connection terminal 4
The coating film 5 is formed so as to cover both of them.
Is patterned so as to cover the first electrode 2 and expose the connection terminal 4 (see FIG. 2D).

Thereafter, the second base material 6 is electrically connected to the exposed connection terminals 4 (see FIGS. 3A and 3B).

In this case, it is preferable to use a photolithography method for patterning the coating film 5. For example, after forming the first electrode 2 and the connection terminal 4, a resist is formed on the surface of the connection terminal 4. 20 (see FIG. 2 (c)). * The coating film 5 is formed so as to cover the first electrode 2 and the resist 20. 5 can be removed together with the method.

Next, effects of the present embodiment will be described.

According to the present embodiment, since the coating film 5 is patterned by a method such as photolithography, which can easily control the accuracy, the exposed film is exposed as compared with the case where masking is used as in the conventional example. Therefore, only the connection terminal 4 can be exposed, and the first electrode 2 can be kept covered. as a result,
Foreign matter is less likely to adhere to the first electrode 2, preventing corrosion and disconnection of the first electrode 2 due to foreign matter adherence, and reliability of the electric circuit device itself can be obtained.

Further, it is possible to prevent foreign substances from adhering between the adjacent first electrodes 2 and to avoid their conduction, and also to make the pitch of the first electrodes 2 finer.

Further, since it is difficult for foreign matter to adhere to the first electrode 2, a reduction in manufacturing yield can be prevented.

Still further, as described above, the first
Since the adhesion of foreign matter between the electrodes 2 is prevented,
In the liquid crystal device, deterioration of image quality can be avoided,
A finer image can be displayed by making the pitch of the electrodes 2 finer.

[0035]

The present invention will be described below in more detail with reference to examples.

Example 1 In this example, a liquid crystal device (electric circuit device) 1 shown in FIG. 1 was prepared.

First, the structure of the liquid crystal device 1 manufactured in this embodiment will be described with reference to FIGS. 1 (a) and 1 (b).

The illustrated liquid crystal device 1 includes a liquid crystal panel (liquid crystal element) P. The liquid crystal panel P is configured by sandwiching a liquid crystal 11 between a pair of glass substrates 3 and 10. A large number of information electrodes (first electrodes) 2 are formed on the surface of one glass substrate (first substrate) 3 at a pitch of about 0.06 mm, and both edges of the glass substrate 3 (FIG. 1A) (Upper and lower edges shown in FIG. 4), connection terminals 4 connected to the respective information electrodes 2
Many were formed in the shape shown in FIG. As shown in detail in FIG. 1B, an end electrode 12 and connection terminals 12a and 12b of the end electrode 12 are formed near each connection terminal 4.
Further, an insulating film (coating film) 5 and an alignment film (not shown) were formed on the surface of the glass substrate 3 so as to cover the electrode 2 and expose the connection terminals 4, 12a, 12b. here,
FIG. 4A is a diagram showing the shape of the connection terminals 4 and 12a, and FIG. 4B is a detailed view of a portion B of FIG.

Further, a driving IC was used as the second base member 6, and the connection terminals 4, 12a and the terminals of the driving IC 6 were electrically connected to each other via the ACF 7 (COG mounting).

Further, as shown in FIG. 1 (a), driver circuit boards 8 are respectively disposed at positions facing both the upper and lower edges and the left edge of the liquid crystal panel P, and the circuit pattern 8a and the The connection terminals 12b on the panel side were connected via the flexible substrate 9 and the ACF7.

The liquid crystal panel P prepared in this embodiment
Has a diagonal size of 15 inches and a QUXGA (3200 ×
2400 pixels).

The information electrode 2 was made of ITO having a thickness of 800 °.

Further, the insulating film 5 was made of tantalum oxide (TaOx) having a thickness of 900 °.

Next, a method of manufacturing the liquid crystal device 1 will be described with reference to FIGS.

First, an ITO film 22 was formed on the entire surface of the glass substrate (first base material) 3 by using a sputtering method.
Then, a resist film (OFPR # 800 manufactured by Tokyo Ohka Co., Ltd.) is formed so as to cover the ITO film 22, and exposure is performed using an exposure mask to pattern the resist film 23 (see FIG. 2A). 2), patterning of the ITO film 22 was performed by etching with a hydrochloric acid-based etchant (see FIG. 2B). Thus, the information electrode 2, the connection terminal 4, the end electrode 12, and the connection terminals 12a and 12b were formed on the surface of the glass substrate 3. Note that the resist film 2
Stripping of 3 was performed after these electrodes 2 and the like were formed.

Further, a resist film was formed so as to cover the electrodes 2 and the like, and patterning was performed by photolithography so that the resist film exposed the information electrodes 2 and covered the connection terminals 4, 12a, and 12b. (Figure 2
(See reference numeral 20 in (c)).

Then, the insulating film 5 is formed by sputtering so as to cover the entire information electrode 2 and the resist film 20.
Was formed.

Thereafter, the connecting terminals 4 and 12 were removed by using a stripper (Stripper-10 manufactured by Tokyo Ohka Co., Ltd.), ultrasonic waves or a brush.
The insulating film in the portion where the a and 12b are arranged is replaced with a resist film 20.
And the insulating film 5 was patterned (lift-off method). Thus, the information electrode 2 itself is covered with the insulating film 5, and the connection terminals 4, 12a, and 12b are exposed (see FIG. 2D).

Further, an alignment film (not shown) was formed on the surface of the insulating film 5 by a printing method or the like, and this alignment film was subjected to a rubbing treatment.

Then, the two glass substrates 3 and 10 were bonded to each other with a predetermined gap therebetween, a panel was cut out by scribing, and a liquid crystal 11 was injected into the gap between the substrates to form a liquid crystal panel P.

Then, the portions of the connection terminals 4, 12a,... Are washed, and ACF7 (CP manufactured by Sony Chemical Co., Ltd.)
7321SP) and connecting terminals 4, 12a
The driving ICs 6 are aligned with respect to (see FIG. 3A), and all the driving ICs 6 are
(See FIG. 3 (b)). The heating temperature of the tool bar 24 was set to 80 ° C., the pressing force was set to 300 kgf, and the pressing time was set to 5 seconds. Thereby, the terminals of the driving IC 6 and the connection terminals 4, 1
2a were individually and electrically connected.

Further, the connection between the circuit pattern 8a of the driver circuit board 8 and the liquid crystal panel P is performed by the flexible board 9 and the ACF 7 (see FIG. 3C), and each connection portion is formed of a sealing resin (not shown). Toshiba Silicone SE900
0).

Next, the effect of this embodiment will be described.

The present inventor conducted a continuous durability test (90% RH at a temperature of 45 ° C.) on the manufactured liquid crystal device 1. As a result, no break or corrosion occurred at the connection even after 1000 hours. Was.

Further, the present inventor has proposed that the driver circuit board 8
When a predetermined signal was applied to the liquid crystal panel P via the flexible substrate 9 to conduct a continuity test of all the connection portions, the pitch of the information electrodes 2 was about 0.06 mm, and
Despite being a high-definition liquid crystal panel of XGA (3200 × 2400 pixels), no continuity between adjacent information electrodes was found at all.

Note that the present inventor did not use a photolithography method for patterning the insulating film 5 but made a liquid crystal device similar to that described above using a conventional masking method for comparison, and conducted the above-described conduction. Upon inspection, continuity was found at three locations. Further, when the same continuous durability driving test as described above was performed, corrosion occurred at the connection portion in about 750 hours, and the effectiveness of the present invention was confirmed.

(Example 2) A liquid crystal panel was prepared in the same manner as in Example 1 except that SiOx (silicon oxide) having a thickness of 500 ° was used for the insulating film 5.

According to this embodiment, the same effects as those of the first embodiment were obtained.

[0059]

As described above, according to the present invention,
For example, since the coating film is patterned by a method such as photolithography which is easy to control the accuracy, the exposed area can be reduced as compared with the case where masking is used as in the conventional example, and only the connection terminals are used. And the first electrode can be left covered.
As a result, foreign matter is less likely to adhere to the first electrode, and corrosion or disconnection of the first electrode due to the foreign matter is prevented, so that the reliability of the electric circuit device itself can be obtained.

In addition, it is possible to prevent foreign substances from adhering between the adjacent first electrodes, to avoid conduction thereof, and to make the pitch of the first electrodes fine.

Further, since it is difficult for foreign matter to adhere to the first electrode, it is possible to prevent a reduction in manufacturing yield.

Further, as described above, the first
Since the adhesion of foreign matter between the electrodes is prevented, in the liquid crystal device, deterioration in image quality can be avoided, and the pitch of the first electrodes can be reduced to display a high-definition image.

[Brief description of the drawings]

FIG. 1 is a plan view showing a structure of a liquid crystal device as one embodiment of an electric circuit device according to the present invention, and FIG.
FIG.

FIG. 2 is a diagram illustrating an embodiment of a method for manufacturing the liquid crystal device shown in FIG.

FIG. 3 is a diagram illustrating an embodiment of a method for manufacturing the liquid crystal device shown in FIG.

FIG. 4A is a diagram showing a shape of a connection terminal, and FIG.
3A is a detailed view of a part B of FIG.

5A is a plan view for explaining an example of the structure of a conventional liquid crystal device, and FIG. 5B is a cross-sectional view taken along the line CC of FIG.

[Explanation of symbols]

 Reference Signs List 1 liquid crystal device (electric circuit device) 2 information electrode (first electrode) 3 glass substrate (first substrate) 4 connection terminal 5 insulating film (coating film) 6 driving IC (second substrate) 10 glass substrate ( Substrate) 11 liquid crystal 20 resist 36 TAB film (second base material) P liquid crystal panel (liquid crystal element)

Claims (9)

[Claims] 1. A step of forming a plurality of first electrodes and connection terminals of the first electrodes on a surface of a first base material, and covering the first electrodes and covering the connection terminals so that the connection terminals are exposed. A method for manufacturing an electric circuit device, comprising: a step of forming a film; and a step of electrically connecting a second electrode formed on a second base material to the exposed connection terminal. After forming the connection terminal, a step of forming the coating film so as to cover both of them, and a step of patterning the coating film so that the connection terminal is exposed, A method for manufacturing an electric circuit device, comprising: 2. The method according to claim 1, wherein the patterning of the coating film is performed using a photolithography method. 3. After forming the first electrode and the connection terminal, a step of arranging a resist on the surface of the connection terminal is performed. Then, the coating is performed so as to cover the first electrode and the resist. The method for manufacturing an electric circuit device according to claim 2, wherein a film is formed and the resist is removed together with the coating film. 4. A liquid crystal element is formed by sandwiching liquid crystal between a pair of substrates, wherein the plurality of first electrodes and connection terminals of the first electrodes are provided on a surface of at least one of the first base materials. The electric circuit device according to any one of claims 1 to 3, wherein the electric circuit device is formed, and a second electrode formed on the second base material is electrically connected to the connection terminal. Manufacturing method. 5. The method according to claim 4, wherein the second substrate is a driving IC for generating a driving signal to be applied to the liquid crystal element. 6. The method according to claim 1, wherein the second base material is a flexible TAB.
The electric circuit according to claim 4, wherein the electric circuit is a film, and a driving IC for generating a driving signal applied to the liquid crystal element is mounted on a surface of the second base material. Device manufacturing method. 7. The method for manufacturing an electric circuit device according to claim 4, wherein the coating film is an insulating film. 8. The method according to claim 7, wherein the insulating film is transparent. 9. The method according to claim 7, wherein the insulating film is a metal oxide film.