JP2000104166A - Formation of transparent electrically conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form electrically conductive films having the same etching rate without being influenced by the fact whether it is on an organic film or on an inorganic film and to reduce the number of stages and cost by executing film formation in such a manner that oblique incidence components are largely taken in the initial stage of the formation of transparent electrically conductive films. SOLUTION: Preferably, the film forming temp. of transparent electrically conductive films is the one below the deteriorating temp. of an organic insulating film formed below the transparent electrically conductive films. The transparent electrically conductive films can be formed without deteriorating the organic insulating film. When film formation is executed in such a manner that, in the initial stage of the film formation at the time of ITO sputtering, oblique incidence components are largely taken in, and the flow rate ratio between Ar and oxygen and the film forming temp. are controlled, ITO films in which the etching rate is not influenced by the fact whether the base is an organic film or an inorganic film can be formed. Since the difference in the just etching time of the transparent electrically conductive films formed on the organic insulating film and on the inorganic film is made small, the transparent electrically conductive films formed on the organic insulating film and on the inorganic film can simultaneously be etched, each photostage and etching stage therefor may be executed only by one stage, by which the cost can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a transparent conductive film used for a liquid crystal display device and a color filter.

[0002]

2. Description of the Related Art There is an increasing demand for an active matrix type LCD display driven by a TFT (thin film transistor) to have a high definition, a high aperture ratio and a large size. In order to realize a high aperture ratio among them, a high aperture ratio structure in which an interlayer insulating film is provided on a TFT and a pixel electrode is formed of a transparent conductive film thereon is adopted. In this interlayer insulating film, S
Inorganic materials such as iN were used, but recently,
Organic materials such as photosensitive acrylic resin are also used.

[0003]

When a transparent conductive film is formed on a photosensitive acrylic resin, an organic film, glass, S
The etching rate of the transparent conductive film formed thereon differs depending on the material such as the inorganic film of iNx. Therefore, it is necessary to separately etch the transparent conductive film on the organic film and the inorganic film. And increased costs.

FIG. 1A is a plan view of an active matrix substrate of a liquid crystal display device having a high aperture ratio structure, and FIG. T formed on glass substrate 0
An organic insulating film 7 is formed as an interlayer insulating film on the FT 6, the source line 3, and the gate insulating film 5. In the organic insulating film 7, except for the region B where the TFT is formed, the terminal A is formed for taking out the terminal 11 for attaching the TCP.
In the region, the organic insulating film 7 has been removed.

[0005] A transparent conductive film for an electrode is formed thereon by sputtering, and the transparent conductive film is patterned to form a pixel electrode 8 and a TCP mounting terminal 11.

However, under the conventional transparent conductive film formation conditions, as can be seen from FIG. 2A, the transparent conductive film on the inorganic film has a just etching time longer than that of the transparent conductive film on the organic film, and the organic conductive film has a longer etching time. When the etching time is adjusted to the transparent conductive film on the film, the transparent conductive film on the inorganic film is under-etched, and when the etching time is adjusted to the transparent conductive film on the inorganic film, the transparent conductive film on the organic film is over-etched. Therefore, it is necessary to perform etching separately in the region A and the region B. In order to form the picture element electrode 8 and the terminal 11 for attaching the TCP by patterning, as shown in FIG. Two etching steps are required.

The present invention aims at increasing the number of steps and reducing the cost due to the difference between the etching rates of the transparent conductive film on the organic film and the inorganic film, and reducing the cost. To provide a method for forming a transparent conductive film having the following.

[0008]

According to a first aspect of the present invention, a transparent conductive film is formed by incorporating a large amount of obliquely incident components at an initial stage of film formation. The invention according to claim 2 is characterized in that the film forming temperature of the transparent conductive film is lower than the deterioration temperature of the organic insulating film formed below the transparent conductive film.

The operation of the present invention will be described below. According to the method for forming a transparent conductive film according to the first aspect of the present invention, a transparent conductive film having an etching rate independent of an organic film or an inorganic film can be formed. Increase in the number of processes and cost increase.

According to the method for forming a transparent conductive film according to the second aspect of the present invention, a transparent conductive film can be formed without deteriorating the organic insulating film.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for producing a transparent conductive film according to the present embodiment will be described below.

[0012] Using a magnet swinging single-wafer processing type Subatta device, the transparent conductive film _{ITO (In 2 0 3: 95} %, Sn0
₍₂ : 5%) Using a target, a film was formed by a reactive sputtering method in an atmosphere of a mixture of Ar and oxygen.

The sputtering conditions were as follows: a film formation temperature of 170 ° C .;
Ar gas: 100 sccm, oxygen gas: 2.0 sccm, sputtering pressure: 0.65 Pa, and in order to incorporate a large amount of obliquely incident components in the initial stage of film formation, the magnet swing speed was set to 10 mm / sec, which was 1/4 of the conventional film formation condition. age,
Film-forming condition 1 for forming a film having a thickness of 1000 °. Film forming temperature 17
1. 0 ° C., Ar gas 100 sccm, oxygen gas Oscc
m, the sputtering pressure is 0.65 Pa, and in order to incorporate a large amount of oblique incident components in the initial stage of film formation, the magnet swing speed is set to 5 mm / sec, which is 1/8 of the conventional film formation conditions, and a thickness of 1000 mm is formed. Two types of film formation conditions 2 were used.

FIG. 3 (a) shows the operation of the magnet of the magnet swing type single-wafer batter device. In FIG. 3A, 12 is an ITO target, 13 is a magnet, 1
4 is the magnet swing upper limit, 15 is the magnet swing lower limit,
Reference numeral 16 denotes a magnet swing distance, and the magnet moves in the direction of the arrow 17. FIG. 3B is a table showing the moving speed of the magnet under the film forming conditions of the present invention and the conventional film forming conditions.

The transparent conductive film formed as described above was patterned into a desired shape by a photolithography step and an etching step, and etching was performed with a hydrochloric acid-based etchant to evaluate the just etching time. FIG. 2A shows the result of the just etching time, and FIG. 2B shows the result of the temperature dependence of the just etching time under the conditions of the present invention.

From FIG. 2A, it can be seen that the conventional film forming conditions
It can be seen that there is little difference between the just etch time of the film forming conditions of the present embodiment and that of the organic film and the inorganic film. FIG.
(B) shows that the difference in the just etch time between the transparent conductive film formed on the organic film and the transparent conductive film formed on the inorganic film can be further reduced by increasing the film forming temperature.

Further, from FIG. 2 (c), it can be seen that an excessively high deposition temperature causes deterioration of the organic film.

As is apparent from the above results, if a large amount of oblique incident components are taken in the initial stage of film formation at the time of ITO sputtering and the film is formed by adjusting the Ar, the oxygen flow rate and the film formation temperature, the etching rate becomes lower than the base. An ITO film which is not affected by a certain organic film or inorganic film can be formed.

According to the present invention, the transparent conductive film on the organic film and the transparent conductive film on the inorganic film can be etched at the same time. As shown in FIG. As a result, the photo process and the etching process can be reduced one by one each in comparison with the conventional film forming method, and the cost can be reduced accordingly.

[0020]

According to the first aspect of the present invention, the difference in the just etching time between the transparent conductive film formed on the organic insulating film and the transparent conductive film formed on the inorganic film is reduced.
As a result, the transparent conductive film formed on the organic insulating film and the transparent conductive film formed on the inorganic film can be simultaneously etched, so that only one photo step and one etching step are required, thereby reducing costs. Was.

According to the second aspect of the present invention, a transparent conductive film can be formed without deteriorating the organic insulating film.

[Brief description of the drawings]

FIG. 1 is an example of a plan view and a cross-sectional view of a high aperture ratio pattern structure according to an embodiment of the present invention.

2A is a graph showing the just etching time under film forming conditions, FIG. 2B is a graph showing the temperature dependence of the just etching time under the conditions of the present invention, and FIG. 2C shows the effect of the film forming temperature on the organic film. It is a table showing.

FIG. 3A is a diagram showing a magnet swing pattern.
(B) A table showing the magnet swing speed for each film forming condition.

FIG. 4 is a diagram showing a process flow under conventional film forming conditions and a process flow of the present invention.

[Explanation of symbols]

 0 Glass substrate 1 Gate wiring 2 Common wiring 3 Source wiring 4 Anodized film 5 Gate insulating film 6 TFT 7 Organic insulating film 8 Pixel electrode 9 Gate electrode 10 Source electrode 11 TCP mounting terminal 12 Target 13 Magnet 14 Magnet swing upper limit 15 Lower limit of magnet swing 16 Magnet swing distance

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H092 JA24 MA05 MA13 MA17 NA27 PA01 PA08 4K029 BA50 BC09 BD00 CA15 EA08 4M104 AA10 BB36 DD37 DD39 GG20 5F103 AA08 BB14 BB22 DD30 HH04 HH07 LL13 LL20 NN01 PP11 RR08

Claims (2)

[Claims] 1. A method for forming a transparent conductive film, wherein a film is formed by incorporating a large amount of oblique incident components at an initial stage of the formation of the transparent conductive film. 2. The transparent conductive film according to claim 1, wherein a film forming temperature of the transparent conductive film is lower than a deterioration temperature of an organic insulating film formed below the transparent conductive film. Film formation method.