KR20180090081A - Etching solution composition for silver-containing layer and manufacturing method for an array substrate for display device using the same - Google Patents

Abstract

The present invention relates to an etching solution composition for a silver-containing thin film containing 5.0 to 48.0 wt% of phosphoric acid, 2.0 to 9.0 wt% of nitric acid, 5.0 to 15.0 wt% of acetic acid, 0.1 to 5.0 wt% of ferric nitrate, and the remaining amount of water. The present invention also relates to a manufacturing method of an array substrate for a display device using the etching solution composition. The etching solution composition can perform an excellent side etch when etching a metal film containing silver, does not damage a lower data wire, and can maintain the etching uniformity.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film etching solution composition containing silver, and a method of manufacturing an array substrate for a display device using the thin film etching solution composition. 2. Description of the Related Art [

The present invention relates to a silver-containing thin film etchant composition and a method of manufacturing an array substrate for a display using the same.

As we enter the era of information age, we are processing and displaying large amounts of information.

The display device field has been rapidly developed, and various flat panel displays have been developed in response to this. Examples of such flat panel display devices include a liquid crystal display device (LCD), a plasma display panel (PDP), a field emission display device (FED), an organic light emitting device Light Emitting Diodes (OLED).

For example, since OLEDs can be driven at low voltages while emitting light by itself, they are rapidly applied to small display devices such as portable devices, and they are commercialized in large-sized TVs Is in the spotlight. As the display device becomes a large screen, the wiring becomes longer and the wiring resistance increases. Therefore, a method of making the display device large-sized and realizing a high resolution by lowering the resistance is demanded.

In order to solve the problem of signal delay due to an increase in resistance, it is necessary to form the wiring with a material having a resistivity as low as possible. As part of such efforts, a multilayer film including a silver (Ag: specific resistance: about 1.59 mu OMEGA.) Film, a silver alloy film or a silver film or a silver alloy film having a low resistivity, a high luminance and a conductivity as compared with other metals, Reflective film, and the like, efforts are being made to realize a large-sized flat panel display device, high resolution and low power consumption, and an etching liquid for application to such materials is required.

In the case of using a thin film containing silver (Ag), the occurrence of re-adsorption of silver in a low-resolution display device is not a problem, but the re-adsorption of silver is a problem in a high-resolution display device technology. Further, in the case of an etchant composition containing phosphoric acid, acetic acid, and nitric acid (Korean Registered Patent Publication No. 10-0579421), problems such as viscosity have occurred, and when an etching process is performed using a conventional tilted Etcher equipment A difference in side etch, that is, a difference in skew, between the upper portion and the lower portion occurred. Therefore, there is a need to develop an etchant that can solve such problems.

Korean Patent Registration No. 10-0579421

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems of the prior art, and it is an object of the present invention to provide a method of etching a metal film including silver with excellent side etch (S / E) The present invention provides an etchant composition for a silver-containing thin film which is capable of performing a fine etching while maintaining a high etching rate and improving the problem of skew differences between an upper portion and a lower portion when an etching process is performed using silver residue and re- .

It is another object of the present invention to provide a method of manufacturing a display device using the etchant composition.

The present invention relates to a composition comprising 5.0 to 48.0% by weight of phosphoric acid; 2.0 to 9.0% by weight of nitric acid; 5.0 to 15.0% by weight acetic acid; 0.1 to 5.0% by weight of ferric nitrate; And a balance of water.

It is another object of the present invention to provide a method of manufacturing an array substrate for a display device using the etchant composition.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems of the prior art, and it is an object of the present invention to provide a method of etching a metal film including silver with excellent side etch (S / E) The present invention provides an etchant composition for a silver-containing thin film which is capable of performing a fine etching while maintaining a high etching rate and improving the problem of skew differences between an upper portion and a lower portion when an etching process is performed using silver residue and re- do.

In addition, the present invention provides a method of manufacturing an array substrate for a display device using the etchant composition.

1 is a photograph showing an experimental result of etching a silver-containing thin film with the etchant composition of Example 1. Fig. 1 (A) is a scanning electron micrograph (SEM) photograph showing the degree of re-adsorption of silver after etching the silver-containing thin film with the silver etching composition of Example 1, and (B) (S / E) after one-side etching (S / E).
FIG. 2 is a photograph showing an experimental result of etching a silver-containing thin film with the etchant composition of Comparative Example 8. FIG. (A) is a scanning electron micrograph (SEM) photograph showing the degree of re-adsorption of silver after etching the silver-containing thin film with the composition of Comparative Example 8, and the silver re-adsorption result (B) (SEM) photograph showing the degree of side etching (S / E) after etching.

The present invention relates to a composition comprising 5.0 to 48.0% by weight of phosphoric acid; 2.0 to 9.0% by weight of nitric acid; 5.0 to 15.0% by weight acetic acid; 0.1 to 5.0% by weight of ferric nitrate; And a remaining amount of water.

In the present invention, the silver-containing thin film may include, but is not limited to, a single film of silver or silver alloy, or a multilayer film composed of the single film and the transparent conductive film.

In the present invention, the transparent conductive film may be at least one selected from the group consisting of indium tin oxide (ITO), zinc oxide indium (IZO), tin zinc indium (ITZO) and / or gallium indium gallium indium (IGZO) , But is not limited thereto.

 In the present invention, the silver alloy silver may be at least one selected from the group consisting of silver (Ag) and at least one element selected from the group consisting of nickel (Ni), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), tin (Sn), palladium (Nd), niobium (Nb), molybdenum (Mo), magnesium (Mg), tungsten (W), protactinium (Pa), aluminum (Al), and titanium , But is not limited thereto.

In the present invention, the multilayer film composed of a single film and a transparent conductive film may be a transparent conductive film / silver, a transparent conductive film / silver alloy, a transparent conductive film / silver / transparent conductive film or a transparent conductive film / silver alloy / transparent conductive film , But is not limited thereto. The transparent conductive film / silver / transparent conductive film may be a-ITO / AgX / a-ITO, but is not limited thereto.

In the present invention, the skew difference refers to the difference in the side etching (S / E) between the upper end portion and the lower end portion, and the upper end portion refers to the upper portion of the substrate that is sloped into the etching apparatus for etching, Quot; portion " means an end portion of a metal film which forms an inclination.

In the present invention, the remaining amount of water is included so that the total weight of the total composition is 100% by weight.

The transparent conductive film of the present invention is characterized by being indium tin oxide (ITO), zinc indium oxide (IZO), zinc indium tin oxide (ITZO) and gallium indium gallium indium (IGZO).

Phosphoric acid (H ₃ PO ₄ ) contained in the etching solution of the present invention is a component used as a main dissociation agent and performs a wet etching by oxidizing silver (Ag) and a transparent conductive film. The content thereof may be 5 to 48% by weight based on the total weight of the etchant composition. If the content of phosphoric acid is less than the above range, the etching rate of silver may be lowered and the etching profile may be defective and the Ag re-adsorption may increase. If the content exceeds the above range, the etching rate of the transparent conductive film is lowered, The tip of the upper and lower transparent conductive films is generated, which is a problem in the subsequent process.

The nitric acid (HNO ₃ ) contained in the etching solution of the present invention is a component used as an oxidizing agent, and performs a wet etching by oxidizing silver (Ag) and the transparent conductive film. The content thereof may be 2 to 9% by weight based on the total weight of the etchant composition. If the content of nitric acid is less than the above range, the etching rate of silver (Ag) and the transparent conductive film (for example, ITO or the like) may be lowered, resulting in unevenness of etch uniformity in the substrate. When the amount of the nitric acid exceeds the above range, the etch rate of the upper and lower transparent conductive films is accelerated, and an undercut of the upper and lower transparent conductive films is disadvantageously caused in a subsequent process.

Acetic acid (CH ₃ COOH) contained in the etching solution of the present invention is a component used as a co-oxidant, and performs a wet etching by oxidizing silver (Ag). The content thereof may be 5 to 15% by weight based on the total weight of the etchant composition. If the content of acetic acid is less than the above range, unevenness in etching rate in the substrate may cause unevenness. If the content of acetic acid exceeds the above range, bubbles may be generated. If such bubbles are present in the substrate, And the Ag re-adsorption may occur.

Ferric nitrate (Fe (NO ₃ ) ₃ ) in the etching solution of the present invention is a component used as a co-oxidant and an Ag ligand, and has an effect of reducing Ag re-adsorption to a thin film upon wet etching, The etch rate can be controlled so that the difference in side etch between the upper and lower portions of the metal film, that is, the difference in skew between the upper portion and the lower portion, is minimized by being included in the etchant composition. The content thereof may be 0.1 to 5.0% by weight based on the total weight of the etchant composition. When the content of the ferric nitrate is less than the above range, the uniformity of the etching in the substrate may be reduced, and a portion of the substrate may be partially left in the substrate. If the content exceeds the above range, the etching rate may be lowered, There is a problem in the process because a tip is formed in the upper indium oxide film.

The etchant of the present invention can be applied not only to a single film of silver or silver alloy but also to a triple film composed of a transparent conductive film / silver, a double conductive film of a transparent conductive film / silver alloy, a transparent conductive film / silver / transparent conductive film, It is possible to etch the silver (silver alloy) and the lower transparent conductive film with this etching solution after etching the transparent conductive film on the upper second etching step with another etching solution, and the upper transparent conductive film is etched with the other etching solution, And the lower transparent conductive film is etched with another etchant after etching.

In the case where the etchant composition of the present invention is used for a single film made of silver (Ag) or a silver alloy used as a wiring and a reflective film in the manufacture of a display device and a multi-layered film composed of the single film and the transparent conductive film, And it is also possible to improve the problem of Ag reattachment caused by damage of the data line of the pad portion.

The present invention provides a method of manufacturing a semiconductor device, comprising: a) forming a gate wiring on a substrate; b) forming a gate insulating layer on the substrate including the gate wiring; c) forming an oxide semiconductor layer on the gate insulating layer; d) forming source and drain electrodes on the oxide semiconductor layer; And e) forming a pixel electrode or reflective film connected to the drain electrode; (E) forming a silver (Ag) -containing thin film on a substrate, etching the thin film with a silver-containing thin film of the present invention to form a pixel electrode or a reflective film The method comprising the steps of: forming an array substrate on a substrate;

In the present invention, the array substrate for a display device manufactured by the above-described manufacturing method can be used for an organic light emitting element (OLED) or a liquid crystal display (LCD), but is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the following examples illustrate the present invention and the present invention is not limited by the following examples, and various modifications and changes may be made. The scope of the present invention will be determined by the technical idea of the following claims.

< Example  And Comparative Example > Etchant  Composition manufacturing

10 kg of each of the etching solution compositions of Examples 1 to 9 and Comparative Examples 1 to 8 was prepared according to the compositions and contents shown in Table 1 below, and the remaining amount of water was included so that the total weight of the etching solution composition was 100 wt% Respectively.

[Table 1]

<Experimental Example>

A silver nano wire was coated on a substrate together with an overcoat material, and a photoresist was exposed on the substrate and patterned through a development process. The substrate was cut into a size of 500 X 600 mm using a diamond knife to prepare a specimen.

Using the etchant compositions of Examples 1 to 9 and Comparative Examples 1 to 11, performance tests were carried out as follows.

Experimental Example 1: Ag Etching amount  evaluation

The silver etching compositions of Examples 1 to 9 and Comparative Examples 1 to 11 were placed in an experimental apparatus of a spray type etching method (model name: 5.5 ETCHER, Pro Wet Company), and the temperature was set to 40 ° C., When the temperature reached 40 ± 0.1 ° C, the etching process of the specimen was performed. The total etching time was 100 seconds. After the substrate was injected and the etching was started for 100 seconds, the substrate was taken out, washed with deionized water, dried using a hot air drier, and photoresist was removed using a photoresist stripper. After washing and drying, the samples were etched using an electron microscope (SEM; model: SU-8010, manufactured by Hitachi), and the analysis was carried out. The results were evaluated according to the following criteria, and the results are shown in Table 2 below.

[Ag etching rate evaluation criteria]

⊚: very excellent (unilateral etching (S / E): ≤0.4 μm)

Good: Excellent (unilateral etching (S / E): 0.5 mu m, > 0.4 mu m)

?: Good (unilateral etching (S / E):? 0.6 占 퐉,? 0.5 占 퐉)

X: defective (unilateral etching (S / E): > 0.6 mu m)

Experimental Example 2: Ag  Re-adsorption evaluation (pad part analysis)

The silver etching compositions of Examples 1 to 9 and Comparative Examples 1 to 11 were placed in an experimental apparatus of a spray type etching method (model name: 5.5 ETCHER, Pro Wet Company), and the temperature was set to 40 ° C., When the temperature reached 40 ± 0.1 ° C, the etching process of the specimen was performed. The total etching time was 100 seconds. After the substrate was injected and the etching was started for 100 seconds, the substrate was taken out, washed with deionized water, dried using a hot air drier, and photoresist was removed using a photoresist stripper. After being cleaned and dried, it is etched using a scanning electron microscope (SEM; model: SU-8010, manufactured by HITACHI), and then exposed to a part of different metals such as data lines or a specific region where friction may occur due to bending (Ag) adsorbed on the surface of the substrate was observed through a full observation. The results were evaluated according to the following criteria, and the results are shown in Table 2 below.

[Evaluation criteria of Ag re-adsorption]

◎: Very good (less than 50)

○: Excellent (less than 80)

?: Good (less than 100)

X: Defective (more than 100)

Experimental Example 3: Evaluation of Skew Difference Same as Experimental Example 2 ( equally  Evaluation and analysis of pattern part)

Experiments were carried out in the same manner as in Experimental Example 2, except that the difference (S / E) between unilateral (S / E) difference between the upper and lower portions of the substrate was measured, The results are shown in Table 2 below.

[Difference in unilateral etching of upper part and lower part (i.e., skew difference)]

One side etching (S / E) difference (≤0.1㎛): very good

One side etching (S / E) difference (≤ 0.15 μm,> 0.1 μm): Excellent

Difference in unilateral etching (S / E) (≤ 0.2 ㎛,> 0.15 ㎛): Good

One side etching (S / E) difference (> 0.2 μm): Bad

[Table 2]

ITO / AgX / a-ITO thin films were etched using the etchant compositions having the composition ratios of Examples 1 to 9 and Comparative Examples 1 to 11. As a result, the etchant compositions of Examples 1 to 9 were found to have an Ag etching amount, Ag reabsorption, and unilateral etching (S / E) difference (skew difference). Particularly, in the case of Example 1, the difference (skew difference) in unilateral etching (S / E) between the upper part and the lower part was as excellent as 0.01 mu m, and no Ag re-adsorption occurred. On the other hand, in the case of the etchant compositions of Comparative Examples 1 to 8, both the Ag etching amount, the Ag re-adsorption, and the difference in the side etching (S / E) between the top portion and the bottom portion (i.e., skew difference) . (S / E) difference (i.e., skew difference) between the upper part and the lower part was 0.45 占 퐉 and the amount of Ag re-adsorption was 500. In the case of the comparative example 7 not containing ferric nitrate, (See Fig. 2). In Comparative Example 9 and Comparative Example 10 in which nitrate other than ferric nitrate was used, the difference in unilateral etching (S / E) between the upper portion and the lower portion (i.e., skew difference) was 0.29 and 0.27 mu m, More than 300 re-adsorption problems occurred. Also, in case of Comparative Example 11 in which phosphoric acid was added in an excessive amount, the problem of re-adsorption occurred even though ferric nitrate was used, and the Ag etch amount in the lower portion and the upper portion were both 0.6 μm or more.

Claims (7)

5.0 to 48.0% by weight phosphoric acid;
2.0 to 9.0% by weight of nitric acid;
5.0 to 15.0% by weight acetic acid;
0.1 to 5.0% by weight of ferric nitrate; And
Containing a residual amount of water
Containing thin film.
The silver-containing thin film etching liquid composition according to claim 1, wherein the silver-containing thin film comprises a single film of silver or silver alloy, or a multilayer film composed of the single film and the transparent conductive film.
The transparent conductive film according to claim 2, wherein the transparent conductive film is at least one selected from the group consisting of indium tin oxide (ITO), zinc oxide indium (IZO), zinc indium tin oxide (ITZO), and gallium oxide zinc indium (IGZO) Containing thin film etchant composition.
The method according to claim 2, wherein the silver alloy silver (Ag) and at least one of nickel (Ni), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr), tin (Sn) , One selected from the group consisting of neodymium (Nd), niobium (Nb), molybdenum (Mo), magnesium (Mg), tungsten (W), protactinium (Pa), aluminum (Al), and titanium Containing thin film.
The method according to claim 2, wherein the multilayer film composed of the single film and the transparent conductive film is a transparent conductive film / silver, a transparent conductive film / silver alloy, a transparent conductive film / silver / transparent conductive film or a transparent conductive film / silver alloy / Containing thin film.
a) forming a gate wiring on the substrate;
b) forming a gate insulating layer on the substrate including the gate wiring;
c) forming an oxide semiconductor layer on the gate insulating layer;
d) forming source and drain electrodes on the oxide semiconductor layer; And
e) forming a pixel electrode connected to the drain electrode; The method comprising the steps of:
(E) forming a thin film containing silver (Ag) on a substrate, and etching the thin film containing silver with the etchant composition of the silver-containing thin film of claim 1 to form a pixel electrode or a reflective film. &Lt; / RTI &gt;
The method of claim 6,
Wherein the array substrate for a display device is for a liquid crystal display (LCD) or an organic light emitting diode (OLED).

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