JPH01134812A - Manufacture of conductive film - Google Patents

Abstract

PURPOSE:To easily obtain a conductive film pattern by directly forming a resist layer with an inverse pattern on a translucent board, and overlaying a traslucent conductive film on the whole face, and depositing a conductive film after masking a pattern part, and then removing the conductive film together with the resist. CONSTITUTION:A resist film 2 is directly formed with a negative pattern on a translucent board 1 made of glass, etc. A translucent ITO film 3 is gas phase- deposited on the whole face. Next, a mask is applied to a part to form a conductive pattern (translucent indication electrode) and conductive film 4 such as Au, ITO or the like is formed on the ITO film 3 by gas phase-deposition. Next, a resist layer 2 is melted away and needless conductive films 3, 4 on the resist 2 are removed, when indication electrode 5 by the film and a drawing out electrode 6 of lamination with films 3, 4 can be obtained on the translucent board 1. Using a film for the board will enable plural conductive films to be obtained continuously.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for manufacturing a conductive thin film having a transparent display electrode for use in touch panels, liquid crystal displays, etc. The present invention relates to a method of manufacturing a conductive thin film that can form a conductive thin film.

(Prior Art) In recent years, with the rapid spread of computers, touch panels have become increasingly important as a data input device. In addition, liquid crystal displays are becoming firmly established as a display device to replace CRTs (increasingly, they are now occupying a vertical position).

Devices using transparent display electrodes are used in various fields, and are expected to further expand the market due to their industrial utility. therefore.

Regarding thin films having transparent display electrodes used in these devices, there is also a need to establish a manufacturing method with excellent productivity that can be obtained with higher precision and at lower cost.

Now, when manufacturing a device using such a transparent display electrode, such as a touch panel, a thin film having a transparent display electrode patterned in the vertical direction and a thin film having a transparent display electrode patterned in the horizontal direction are used. are manufactured by stacking them in a mesh pattern with spacers at regular intervals.

The thin films used in such touch panels are conventional.

As shown in FIGS. 3 and 4, first, a transparent conductive film is formed on the entire surface of a transparent substrate such as a polymer film. Then,
A photoresist is applied to the film on which the transparent conductive film is formed. Then, a positive film with a predetermined pattern is placed on top of it and exposed.

The patterned resist is developed and further hardened. After that, the portions of the transparent conductive film that are not covered with the patterned resist are removed by etching.
Thereafter, the photoresist is peeled off to expose the transparent conductive film to form a pattern of transparent display electrodes. Furthermore, in order to form the extraction electrode of the transparent display electrode, the pattern of the transparent display electrode and the position where the extraction electrode is to be formed are aligned, and a portion that will become the extraction part of the extraction electrode from the end of one display electrode is aligned. Then, the pattern of the display electrode and the position where the extraction electrode is to be formed are aligned again, and a conductive paste is printed to form the extraction electrode. In this way, a single device constituent material having a transparent display electrode for manufacturing a touch panel is formed.

(Problems to be Solved by the Invention) As described above, in order to manufacture a conductive thin film used in a touch panel, many steps are required to form a pattern of a transparent conductive film, and moreover, many steps are required to form a pattern of a lead electrode. Since printing is required twice, there are problems such as a long time required, complicated setting of one condition, a great deal of labor, and high costs. Furthermore, since it is necessary to carry out dustproof treatment throughout the entire process consisting of a large number of steps, process control is also difficult. Similar problems also exist with respect to display electrodes for liquid crystal displays and the like.

The present invention is intended to solve the above-mentioned conventional problems, and its purpose is to be able to form conductive films with different surface resistances all at once, with a small number of steps, and with easy operation. An object of the present invention is to provide a method capable of producing a conductive thin film having a transparent display electrode.

(Means for Solving the Problems) The present inventors have arrived at the present invention as a result of intensive research to solve the above-mentioned conventional problems.

That is, in the present invention, a resist layer having a pattern opposite to a desired conductive pattern is directly formed on a transparent substrate, a transparent conductive film is then formed over the entire surface, and a conductive pattern made of the transparent conductive film is then formed. A conductive thin film is formed on the transparent conductive film by vapor phase deposition using a mask on the part to be formed, and then the transparent conductive film formed on the resist layer and the conductive thin film formed thereon are formed together with a resist layer. The gist of the present invention is a method for manufacturing a conductive thin film, which is characterized in that a conductive pattern made of a transparent conductive film and a conductive pattern in which a conductive thin film is laminated on the transparent conductive film are formed.

Hereinafter, two aspects of the present invention will be described in detail based on illustrated examples. 1st
The figure is a schematic sectional view showing the manufacturing process of the method of the present invention. First, a transparent substrate 1 is prepared [FIG. 1(a)]. Here, 9 is the transparent substrate 1.

Examples include organic polymer films such as polyester and polyarylate, organic polymer molded products, and glass.

A pattern made of the resist layer 2 is directly formed on the surface of the transparent substrate 1 (FIG. 1(b)).The pattern formed here is a reverse pattern of the desired conductive pattern, that is, a negative pattern. A photoresist may be used as the resist for forming such a pattern.

A screen-printed resist may also be used.

The resist used is determined depending on the required precision of the display electrode, etc., and there is no particular restriction on the resist used. When using a photoresist, after applying the resist, a negative film or the like on which a predetermined pattern has been formed is combined, exposed to light, and developed by a known method.

Next, a transparent conductive film 3 is formed on the entire surface from above [first
Figure (C)]. In this case, a transparent conductive film 3 is formed on the portion of the resist layer 2 where the pattern is formed,
In other parts, a transparent conductive film 3 is formed on the transparent substrate 1. A vapor phase deposition method is preferable as a method for forming the transparent conductive film, and examples of the vapor phase deposition method include a sputtering method, an ion blasting method, a chemical vapor deposition method (CVD method), a reactive vapor deposition method, and the like. The transparent conductive film may be formed by a spray method, a sol-gel method, etc. other than the vapor phase deposition method (the formation method is not limited at all. As a material for forming the transparent conductive film, indium and tin are used) Doped oxide, i.e. ITO that has indium oxide as its main component and contains tin oxide, tin oxide (Snow)
, indium oxide (In, O□), and zinc oxide doped with aluminum, that is, a mixture of the two containing zinc oxide as a main component and aluminum oxide.

Thereafter, the portion where a conductive pattern (transparent display electrode) consisting of a transparent conductive film is to be formed is masked, and a conductive film 4 is formed on the transparent conductive film 3 by vapor deposition.
Figure (d)]. Therefore, the conductive thin film 4 is laminated on the transparent conductive film 3 in the unmasked portion. When masking as described above, it is possible to mask only the portion where one individual display electrode 5 is to be formed in FIG. 2, which will be described later. It is preferable to mask the individual display electrodes all at once, including the portions to be removed together with the resist near the desired portions. In this way, the conductive thin film 4 is formed on all or part of the portion where the conductive thin film 4 is laminated on the transparent conductive film 3 (extracting electrode) and the portion to be removed together with the resist.

The tape margin method is a method for masking.

Any method may be used as long as it can form a thin film while partially concealing it, such as a vapor deposition mask method. Further, as the conductive thin film, Pd, Au, Ag, Cu, and AI are used.

There is no particular restriction as long as it has conductivity, such as a conductive metal such as In or Sn, a conductive compound such as tin oxide, or a mixture of conductive compounds such as ITO. As the vapor phase deposition method when forming the conductive thin film 4, any method may be used as long as it is possible to form a thin film in a vapor phase, such as sputtering method, ion blating method, CVD method, etc. .

After forming the transparent conductive film 3 and the conductive thin film 4 on the transparent conductive film in this way, by removing the resist layer 2, the unnecessary transparent conductive film and conductive thin film formed on the resist layer 2 are removed all at once. Then, two types of patterns having different conductivities are formed: a conductive pattern consisting of the transparent conductive film 3 and a conductive pattern consisting of the transparent conductive film 3 and the conductive thin film 4 [FIG. 1(e)]. Removal of the resist layer is performed by means such as washing with water, elution with an alkaline solution or solvent, depending on the type of resist.

Thus, on a transparent substrate 1 as shown in FIG. 2, a transparent display electrode 5 made of a transparent conductive film is formed.

A conductive thin film is obtained in which an extraction electrode 6 in which a transparent conductive film and a conductive thin film are laminated is formed.

In the present invention, when a film is used as a transparent substrate, a plurality of conductive thin films can be obtained in succession.

(Example) Next, one embodiment of the present invention will be specifically explained using examples.

Example A polyester film with a film thickness of 125 μm was used as the transparent substrate 1, and a resist 2 was used on the film so that a negative pattern was formed in the areas where the transparent display electrodes and extraction electrodes were to be formed. Hydroxypropyl cellulose was printed by screen printing to form a resist pattern with a thickness of 3 μm. Next, ITO was formed as a transparent conductive film 3 on the entire surface by ion blating method so that the surface resistance value was 500 Ω/hole, and the part where the display electrode was to be formed was hidden using a vapor deposition mask. A conductive thin film 4 was formed by depositing Pd so that the surface resistance value was 10Ω/hole. Next, the resist was washed out with water, and the upper layer of ITO and the laminated ITO and Pd were removed at the same time. After that, water was evaporated in a continuous drying oven to obtain a (TO
A transparent display electrode 5 consisting of 1007 rTo and P
A conductive thin film having an extraction electrode 6 formed by laminating d was obtained.

The time required to obtain such a conductive thin film was approximately 20 minutes per film.

Comparative Example A conductive thin film was manufactured according to the steps shown in FIGS. 3 and 4. A polyester film with a film thickness of 125 μm was used as a transparent substrate, and ITO was formed on the entire surface of the film by an ion blasting method so that the surface resistance value was 500 Ω/hole.

Next, an alkali-developable photoresist (OF OR-800 manufactured by Tokyo Ohka Co., Ltd.) was coated to a film thickness of 1.5 μm, and pre-cured at 80°C in a hot air circulation drying oven.
and dried for 15 minutes. Furthermore, after attaching a positive film and exposing it to light using an exposure machine, it was developed with an alkaline developer and rinsed with pure water.

The resist was cured by heating at 130° C. for 30 minutes as post-cure. After that, immerse it in an aqueous hydrochloric acid solution for 3 minutes to etch the ITO, rinse with pure water, remove the photoresist with a stripping solution, and rinse again with pure water so that no stripping solution or photoresist residue remains. and dried.

After patterning the ITO serving as the display electrode in this manner, the ITO pattern and the print were aligned so that they matched, and carbon paste was printed on the extraction portion at the end of the ITO pattern and dried.

Next, the ITO pattern and the printed position of the conductive paste were again aligned so that they matched, and the conductive paste as one extraction electrode was printed and dried.

In this way, a transparent display electrode made of ITO with a surface resistance of 500 Ω/mm and a 10 Ω/mm made of conductive paste were formed.
An extraction electrode at the mouth was formed to obtain a conductive thin film. The time required to obtain such a conductive thin film was approximately 83 minutes per film.

(Effects of the Invention) Since the present invention has the above configuration, the conventional etching process and printing process of conductive paste for forming the extraction electrode are not necessary.

Transparent display electrodes and extraction electrodes can be formed all at once on a transparent substrate. Therefore, the number of steps is small, the yield is high with simple operations, a conductive thin film can be formed at low cost, and process control is easy.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the manufacturing process of the method of the present invention, FIG. 2 is a plan view showing an example of a conductive thin film obtained by the method of the present invention, and FIGS. 3 and 4 are manufacturing steps of the conventional method. It is a flow chart showing a process. 1. Transparent substrate 2, resist layer 3, transparent conductive film 4, conductive thin film 5, transparent display electrode 6, extraction electrode Patent applicant: Yu-Teiryoku Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) A resist layer with a pattern opposite to the desired conductive pattern should be directly formed on a transparent substrate, then a transparent conductive film should be formed over the entire surface, and then a conductive pattern made of the transparent conductive film should be formed. A conductive thin film is formed on the transparent conductive film by vapor phase deposition with a mask on the part, and then the transparent conductive film formed on the resist layer and the conductive thin film formed on it are removed together with the resist layer. A method for producing a conductive thin film, which comprises forming a conductive pattern made of a transparent conductive film and a conductive pattern in which a conductive thin film is laminated on the transparent conductive film. (2) The manufacturing method according to claim 1, wherein the transparent conductive film is formed by vapor deposition.