KR101403069B1 - Manufacturing method of array substrate for liquid crystal display - Google Patents

Abstract

The present invention relates to a method of manufacturing a TFT array substrate for a liquid crystal display,

A step of forming a molybdenum-based metal / aluminum-based metal double layer on a substrate in the step of forming a gate electrode, etching the substrate with an etching composition to form a gate wiring, and a step of forming an indium oxide film in the step of forming a pixel electrode, To form a pixel electrode,

Wherein the etchant composition comprises A) from 2 to 5% by weight of iron oxide (Fe (NO ₃ ) ₃ ), from 0.1 to 1% by weight of a fluorine compound, B) from 8 to 15% by weight of nitric acid (HNO ₃ ) , D) from 2 to 5% by weight of perchloric acid (HClO ₄ ), E) from 0.1 to 5% by weight of at least one potassium salt compound selected from KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ , and F) % Of the total thickness of the substrate. An etchant composition of a molybdenum-based metal / aluminum-based metal double film and an indium oxide film; And a method for etching a molybdenum-based metal / aluminum-based metal double layer or indium oxide layer using the etchant composition.

Molybdenum, aluminum, indium oxide film, etchant composition

Description

TECHNICAL FIELD [0001] The present invention relates to a method of manufacturing an array substrate for a liquid crystal display (LCD)

The present invention relates to a method of manufacturing an array substrate for a liquid crystal display, an etching solution composition of a molybdenum-based metal / aluminum-based metal double film and an indium oxide film, and etching of a molybdenum-based metal / aluminum- ≪ / RTI >

The process of forming a metal wiring on a substrate during manufacture in the manufacture of a semiconductor device for driving a liquid crystal display device typically includes a metal film forming process by sputtering and the like, a photoresist coating process, a photoresist Forming process, and an etching process, and includes a cleaning process before and after the individual unit process. This etching process refers to a process of leaving a metal film in a selective region using a photoresist as a mask. Typically, dry etching using plasma or wet etching using an etching solution is used.

In the above-described semiconductor device, a metal commonly used as a wiring material of a TFT-LCD (Thin Film Transistor-Liquid Crystal Display) is aluminum (Al) or an aluminum alloy. Pure aluminum has a weak resistance to a chemical substance, (Mo), chrome (Cr), tungsten (W), tin (Sn) or the like on the aluminum or aluminum alloy layer A multilayer laminated structure is used.

However, in the case of a Mo / Al bilayer, for example, in the case of wet etching with a conventional aluminum etching solution using phosphoric acid as a main component, since the etching rate of the upper Mo layer is slower than the aluminum etching rate, Which has a cross-section projecting to the outside of the frame. This poor profile results in poor step coverage in the subsequent process and increases the probability that the upper layer will be broken at the slope or the upper and lower metals will be short-circuited.

In recent years, consisting of a In Korea Patent No. 579 511 No. of nitric acid (HNO _3), be iron oxide _{(Fe (NO 3) 3)} , perchloric acid (HClO ₄₎ and ammonium fluoride (NH ₄ F) in order to solve the above A method of batch etch the molybdenum / aluminum double layer using an etchant was presented. However, when the molybdenum / aluminum double-layer substrate is etched with the etching solution, fine etching residues are left on the substrate, causing a leakage current during TFT On / Off driving, Screen distortion may occur. Further, if the indium oxide film is etched with the etchant, an indium oxide film residue remains.

In order to realize a high image quality, an etching solution which does not generate fine etching residues is required. In order to simplify the process, a molybdenum / aluminum double film used as a gate wiring and an indium oxide film used as a pixel electrode are collectively etched It is required to develop an etchant that can be used as a mask.

Accordingly, an object of the present invention is to provide a method for manufacturing a metal-aluminum-metal double-layered structure, which does not generate fine etching residues during etching of a molybdenum-based metal / aluminum-based metal double layer, does not generate residues when the indium oxide film is etched, And to provide an etchant composition capable of batch etching the indium oxide film.

The present invention also provides a method for etching a molybdenum-based metal / aluminum-based metal double layer and an indium oxide layer using the etchant composition.

Further, the present invention provides a method for manufacturing an array substrate for a liquid crystal display device, which comprises a step of etching the molybdenum-based metal / aluminum-based metal double film and / or the indium oxide film by using the above etching solution composition.

In order to achieve the above object,

A) iron oxide (Fe (NO ₃ ) ₃ ),

B) Fluorine compounds,

C) nitric acid (HNO ₃₎

D) Perchloric acid (HClO ₄ ),

E) at least one potassium salt compound selected from KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ and

F) Water

Based metal / aluminum-based metal double film and an indium oxide film.

Further, according to the present invention,

I) forming a molybdenum-based metal / aluminum-based metal double-layer on a substrate;

II) selectively leaving a photoreactive material on the molybdenum-based metal / aluminum-based metal double layer; And

III) A method of etching a molybdenum-based metal / aluminum-based metal double film or a molybdenum-based metal / aluminum-based metal double film or indium oxide film using the etching liquid composition of the present invention.

Further, according to the present invention,

I) forming an indium oxide film on a substrate;

II) selectively leaving a photoreactive material on the indium oxide film; And

III) etching the indium oxide film using the etching solution composition of the present invention.

Further, according to the present invention,

a) forming a gate wiring on the substrate;

b) forming a gate insulating layer on the substrate including the gate wiring;

c) forming a semiconductor layer on the gate insulating layer;

d) forming source and drain electrodes on the semiconductor layer; And

e) forming a pixel electrode connected to the drain electrode

The method comprising the steps of:

In the step a), a molybdenum-based metal / aluminum-based metal double layer is formed on the substrate, and the gate wiring is formed by etching with the etching solution composition of the present invention. In step e), an indium oxide film is formed, And forming a pixel electrode by etching with an etchant composition. The present invention also provides a method of manufacturing an array substrate for a liquid crystal display device.

When the molybdenum-based metal / aluminum-based metal double film or indium oxide film is etched using the etching liquid composition of the present invention, the aluminum-based metal / molybdenum-based metal double film does not generate fine etching residues, It retains the initial etch characteristics due to the minimized galvanic effect and exhibits excellent etch characteristics that do not leave etch residues even if the indium oxide film is etched with the same etchant. Therefore, when the visual liquid composition of the present invention is used to manufacture an array substrate for a liquid crystal display device including a gate electrode formed of a molybdenum-based metal / aluminum-based metal double film and / or a pixel electrode formed of an indium oxide film, The driving characteristics of the display element can be improved, and the molybdenum-based metal / aluminum-based metal double film and the indium oxide film can be simultaneously etched, thereby maximizing the process efficiency.

Hereinafter, the present invention will be described in detail.

According to the present invention,

A) iron oxide (Fe (NO ₃ ) ₃ ),

B) Fluorine compounds,

C) nitric acid (HNO ₃₎

D) Perchloric acid (HClO ₄ ),

E) at least one potassium salt compound selected from KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ , and

F) Water

Based metal / aluminum-based metal double film and an indium oxide film.

In the present invention, the molybdenum-based metal and the aluminum-based metal are concepts including an alloy thereof, and the indium oxide film is a concept including an indium zinc oxide (IZO) film or an indium tin oxide film (ITO).

In the etchant composition of the present invention, nitrate iron (Fe (NO ₃ ) ₃ ) is used as an oxidizing agent for etching molybdenum metal / aluminum metal double film and indium oxide film. The nitrate iron oxide is preferably contained in an amount of 2 to 5% by weight based on the total weight of the etching solution composition of the present invention. If the amount of the nitric oxide is less than 2% by weight, the etching force may be insufficient and sufficient etching may not be performed. If the amount of the nitric oxide exceeds 5% by weight, the etching rate with respect to the molybdenum- The etching rate is slowed, and the upper molybdenum-based metal is excessively angulated and etching non-uniformity may occur.

Among the etching liquid compositions of the present invention, the fluorine compound accelerates the aluminum etching speed when the molybdenum metal / aluminum metal double film is etched, and the etching speed of the indium oxide film when the indium oxide film is etched.

The fluorinated compound is preferably contained in an amount of 0.1 to 1% by weight based on the total weight of the composition. If the amount of the fluorine compound is less than 0.1% by weight, the etching rate of the molybdenum-based metal / aluminum-based metal double film and the indium oxide film becomes slow. When the amount of the fluorine compound is more than 1% by weight, The etching rate of the aluminum-based metal is too fast to cause an overhang molybdenum-based metal overhang. When the indium oxide film is etched, the lower insulating film of the indium oxide film can be attacked.

The fluorinated compound is preferably at least one selected from the group consisting of NH ₄ FHF, KFHF, NaFHF, KF and NaF, and more preferably NH ₄ FHF, but is not limited thereto.

Among the etchant compositions of the present invention, nitric acid (HNO ₃ ) accelerates the etching rate of the molybdenum-based metal / aluminum-based metal double-layered film when it is etched.

The amount of the silver nitrate is preferably 8 to 15% by weight based on the total weight of the composition. If the amount of nitric acid is less than 8 wt%, the etching rate for the molybdenum-based metal / aluminum-based metal double film is slowed down and etching residues may occur. If the amount of nitric acid is more than 15 wt%, the molybdenum- The etch rate is too fast to control the process time.

In the etchant composition according to the present invention, perchloric acid (HClO ₄ ) is used to etch the molybdenum metal / aluminum-based metal double layer by lowering the pH of the etchant, It serves to prevent the residue.

The perchloric acid is preferably included in an amount of 2 to 5% by weight based on the total weight of the composition. When the perchloric acid content is less than 2% by weight, the etching rate for the molybdenum-based metal / aluminum-based metal double film may be slowed or etching residue may be generated. The etching speed is too fast to be controlled, and an attack can be applied to the lower insulating film.

The perchloric acid uses a mechanism of removing etching residues due to strong acidity, but it has a disadvantage that it is difficult to completely remove minute residues. Thus, the fine molybdenum-based metal that can occur in as in the present invention, by the addition of KNO _3, KCH _3C OO and KH ₂ PO ₄ 1 potassium salt of at least one compound selected from the compositions, molybdenum-based metal / aluminum metal double etch stop Thereby preventing re-adsorption of the oxide film (MoOx).

In the etching solution composition of the present invention, at least one potassium salt compound selected from KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ serves to prevent the molybdenum-based metal oxide film from being reabsorbed on the substrate, because the potassium salt compound is molybdenum This is possible because it has a mechanism to remove the metal oxide film.

The KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ Is contained in an amount of 0.1 to 5% by weight based on the total weight of the composition. If the potassium salt compound is less than 0.1 wt%, the molybdenum-based metal oxide film may be re-adsorbed on the substrate. If the potassium salt compound is more than 5 wt%, the residue may remain during the etching of the indium oxide film.

In the etchant composition according to the present invention, water is not particularly limited, but deionized water is preferred. More preferably, deionized water having a resistivity value of 18 M OMEGA / cm or more can be used to show the degree of removal of ions in the water.

In the present invention, the etchant composition of the molybdenum-based metal / aluminum-based metal double layer and the indium oxide layer,

A) 2 to 5% by weight of iron oxide (Fe (NO ₃ ) ₃ )

B) 0.1 to 1% by weight of a fluorine compound,

C) nitric acid (HNO ₃₎ 8 to 15% by weight,

D) 2 to 5% by weight of perchloric acid (HClO ₄ )

E) from 0.1 to 5% by weight of at least one potassium salt compound selected from KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ , and

F) 69 to 87.8% by weight of water.

The at least one potassium salt compound selected from iron nitrate, fluorine compound, nitric acid, perchloric acid and KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ used in the present invention can be produced by a known method, It is preferable to have purity of the solution.

In addition, the etchant composition according to the present invention may further include any additives conventionally used in the art to improve the etching performance, for example, a surfactant, a sequestering agent or a corrosion inhibitor.

Surfactants decrease the surface tension and increase the uniformity of etching. As such a surfactant, a surfactant which is resistant to an etching solution and has compatibility with the surfactant is preferable. Examples thereof include any of anionic, cationic, amphoteric or nonionic surfactants and the like. Further, a fluorine-based surfactant can be used as a surfactant.

The additive is preferably contained in an amount of 0.0001 to 0.01% by weight based on the total weight of the composition.

The etchant composition according to the present invention can collectively etch a molybdenum-based metal / aluminum-based metal double film and an indium oxide film, that is, an indium zinc oxide (IZO) film and an indium tin oxide film (ITO).

The etchant composition according to the present invention does not generate fine etching residues for the molybdenum metal / aluminum-based metal double film and has excellent etching properties. Even when the indium oxide film is etched, the residue is not generated. And has excellent properties to minimize the amount of the particles.

Further, according to the present invention,

I) forming a molybdenum-based metal / aluminum-based metal double-layer on a substrate;

II) selectively leaving a photoreactive material on the molybdenum-based metal / aluminum-based metal double layer; And

III) etching the molybdenum-based metal / aluminum-based metal double-layer film by etching the molybdenum-based metal / aluminum-based metal double-layer film using the etching liquid composition of the present invention.

Further, according to the present invention,

I) forming an indium oxide film on a substrate;

II) selectively leaving a photoreactive material on the indium oxide film; And

III) etching the indium oxide film using the etching solution composition of the present invention.

The photoreactive material is preferably a conventional photoresist material and may be selectively left by conventional exposure and development processes.

Further, according to the present invention,

a) forming a gate wiring on the substrate;

b) forming a gate insulating layer on the substrate including the gate wiring;

c) forming a semiconductor layer on the gate insulating layer;

d) forming source and drain electrodes on the semiconductor layer; And

e) forming a pixel electrode connected to the drain electrode

The method comprising the steps of:

In the step a), a molybdenum-based metal / aluminum-based metal double layer is formed on the substrate, and the gate wiring is formed by etching with the etching solution composition of the present invention. In step e), an indium oxide film is formed, And forming a pixel electrode by etching with an etchant composition. The present invention also provides a method of manufacturing an array substrate for a liquid crystal display device.

In the method of manufacturing an array substrate for a liquid crystal display according to the present invention, the step a) may include: a1) depositing a molybdenum-based metal / aluminum-based metal double layer on a substrate using a vapor deposition method or a sputtering method; And a2) forming the gate wiring by patterning the molybdenum-based metal / aluminum-based metal double layer with the etching solution of the present invention. Here, the method of forming the molybdenum-based metal / aluminum-based metal double-layer on the substrate is not limited to the above-described examples.

In the method for manufacturing an array substrate for a liquid crystal display according to the present invention, in step (b), silicon nitride (SiN _x ) is deposited on a gate wiring formed on a substrate to form a gate insulating layer. Here, the material used in the formation of the gate insulating layer is not limited to silicon nitride (SiN _x ), but a material selected from various inorganic insulating materials including silicon oxide (SiO ₂ ) may be used to form the gate insulating layer have.

In the method for manufacturing an array substrate for a liquid crystal display according to the present invention, in the step c), a semiconductor layer is formed on the gate insulating layer by a chemical vapor deposition method (CVD). That is, an active layer and an ohmic contact layer are sequentially formed, and patterned through dry etching. Here, the active layer is generally formed of pure amorphous silicon (a-Si: H), and the ohmic surface layer is formed of amorphous silicon (n ⁺ a-Si: H) containing impurities. Chemical vapor deposition (CVD) may be used to form the active layer and the ohmic contact layer, but the present invention is not limited thereto.

In the method for manufacturing an array substrate for a liquid crystal display according to the present invention, the step d) includes the steps of: d1) forming source and drain electrodes on the semiconductor layer; And d2) forming an insulating layer on the source and drain electrodes. In the step d1), a metal film is deposited on the ohmic surface layer by sputtering, and the source electrode and the drain electrode are formed by etching with the etching solution of the present invention. Here, the method of forming the metal film on the substrate is not limited to the above-described example. Wherein d2) step, including the inorganic insulating group, or benzocyclobutene (BCB) and acrylic (acryl) resins (resin) containing silicon nitride (SiN _x) and silicon oxide (SiO ₂₎ on the source and drain electrodes The organic insulating material is selected from the group of organic insulating materials to form an insulating layer as a single layer or a double layer. The material of the insulating layer is not limited to those illustrated above. Particularly, when the source and drain electrodes are made of the same material as the gate wiring, the etching composition can be applied to a process for forming source and drain electrodes.

In the method of manufacturing an array substrate for a liquid crystal display according to the present invention, the pixel electrode connected to the drain electrode is formed in step e). For example, a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) is deposited by sputtering and etched using the etchant composition according to the present invention to form a pixel electrode. The method of depositing the indium oxide film is not limited to the sputtering method.

Further, in the method for manufacturing an array substrate for a liquid crystal display device, in the step (e) etching step using the etching solution composition according to the present invention, the attack to the data line including the drain electrode located under the pixel electrode can be minimized , It is possible to manufacture an array substrate for a liquid crystal display device which can improve the driving characteristics of the TFT-LCD and improve the productivity of the array substrate for a liquid crystal display device.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the following examples are intended to illustrate the present invention, and the present invention is not limited by the following examples, but may be variously modified and changed.

Example  1 to 10: Etchant  Preparation of composition

The grades for semiconductor processing Fe (NO ₃ ) ₃ , NH ₄ FHF, HNO ₃ , HClO ₄ , and KNO ₃ were mixed as shown in Table 1 below and deionized water was added so that the total weight of the composition was 100 wt% An etching solution was prepared.

Etchant composition (% by weight) Fe (NO _{3) 3} NH ₄ FHF HNO ₃ HClO ₄ KNO ₃ Deionized water Example 1 2.0 0.3 8 3.0 0.1 Balance Example 2 2.5 0.3 9 2.0 0.2 Balance Example 3 3.0 0.4 10 2.0 0.5 Balance Example 4 3.5 0.4 11 2.0 1.0 Balance Example 5 3.5 0.3 8 5.0 0.2 Balance Example 6 3.5 0.5 12 2.0 0.3 Balance Example 7 4.0 0.8 12 3.0 1.0 Balance Example 8 4.0 1.0 14 4.5 0.7 Balance Example 9 4.5 0.8 12 4.0 2.0 Balance Example 10 5.0 0.9 15 1.0 4.0 Balance

Comparative Example  One: Etchant  Preparation of composition

The etchant composition was prepared by adding deionized water to 3 wt% of Fe (NO ₃ ) ₃ , 0.4 wt% of NH ₄ FHF, 10 wt% of HNO ₃ , ₃ wt% of HClO ₄ , and 100 wt% of the total.

Comparative Example  2: Etchant  Preparation of composition

5% by weight oxalic acid and 95% by weight deionized water.

Test Example  1: molybdenum-based metal / aluminum-based metal Double membrane  And indium Oxide film Etching  Character rating

A molybdenum / aluminum double film was sequentially deposited on the glass substrate by the sputtering method, and the indium oxide film was also deposited by the same method as above. Then, a photoresist of about 1 mu m or so was coated thereon, . The test piece was etched using the spraying method with the etching solutions of Examples 1 to 10 and Comparative Examples 1 and 2. Each of the test pieces etched in Examples 1 to 10 and Comparative Examples 1 and 2 was examined using a scanning electron microscope (SEM; Hitach, S-4700). The results are shown in Table 2 and FIGS. 1 to 4 Respectively.

The criteria for evaluating the etch characteristics of the molybdenum-based metal / aluminum-based metal double film and indium oxide film are as follows.

- Etching Characteristics of Molybdenum Metal / Aluminum Metal Double Layer

?: No fine residue occurred,

X: Fine residue was generated.

- Etching Characteristics of Indium Oxide Film

O: no residue,

X: Residual occurred.

Etch characteristics Molybdenum-based metal / aluminum-based metal double-layer Indium oxide film Example 1 ○ ○ Example 2 ○ ○ Example 3 ○ ○ Example 4 ○ ○ Example 5 ○ ○ Example 6 ○ ○ Example 7 ○ ○ Example 8 ○ ○ Example 9 ○ ○ Example 10 ○ ○ Comparative Example 1 × × Comparative Example 2 × ×

As shown in Table 2 above, the KNO ₃ -free In the etchant composition of Comparative Example 1, a residue of a fine molybdenum oxide film was formed when the molybdenum / aluminum double layer was etched (see FIG. 3), and the etchant composition of Comparative Example 2 containing oxalic acid produced a residue of the indium oxide film ).

However, when the molybdenum / aluminum double film and the indium oxide film were etched with the etching liquid compositions (Examples 1 to 10) according to the present invention, residues (minute residues) were not generated. This fact can be confirmed also in Fig. 1 (surface SEM image of the molybdenum / aluminum double film etched with the etching liquid composition of Example 1) and Fig. 2 (surface SEM image of the indium oxide film etched with the etching liquid composition of Example 1).

Therefore, it can be seen that the etching solution of the present invention exhibits excellent etching characteristics with respect to the molybdenum-based metal / aluminum-based metal and the indium oxide film.

1 is a scanning electron microscope (SEM) image of an entire surface of a molybdenum / aluminum double-layer film etched using the etching solution composition according to Example 1 of the present invention.

FIG. 2 is a scanning electron micrograph of the entire surface after etching the indium oxide film using the etching solution composition according to Example 1 of the present invention. FIG.

FIG. 3 is a scanning electron micrograph of a molybdenum / aluminum metal double film etched using the etchant composition according to Comparative Example 1 of the present invention and observing the entire surface thereof.

4 is an electron micrograph of the surface of the indium oxide film etched using the etchant composition according to Comparative Example 2 of the present invention.

Claims (12)

a) forming a gate wiring on the substrate; b) forming a gate insulating layer on the substrate including the gate wiring; c) forming a semiconductor layer on the gate insulating layer; d) forming source and drain electrodes on the semiconductor layer; And e) forming a pixel electrode connected to the drain electrode The method comprising the steps of: In the step a), a molybdenum-based metal / aluminum-based metal double layer is formed on the substrate, and the gate wiring is formed by etching with the etching composition. In step e), an indium oxide film is formed, Forming an electrode, Wherein the etchant composition comprises A) from 2 to 5% by weight of iron oxide (Fe (NO ₃ ) ₃ ), from 0.1 to 1% by weight of a fluorine compound, B) from 8 to 15% by weight of nitric acid (HNO ₃ ) , D) 2 to 5% by weight of perchloric acid (HClO ₄ ), E) KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ 0.1 to 5% by weight of at least one potassium salt compound selected from the group consisting of potassium and potassium, and F) 69 to 87.8% by weight of water. The method according to claim 1, wherein the fluorinated compound is at least one selected from the group consisting of NH ₄ FHF, KFHF, NaFHF, KF, and NaF. The method according to claim 1, wherein the indium oxide film is an indium zinc oxide film (IZO) or an indium tin oxide film (ITO). The method of manufacturing an array substrate for a liquid crystal display according to claim 1, wherein the liquid crystal display array substrate is a thin film transistor (TFT) array substrate. For the total weight of the composition, A) 2 to 5% by weight of iron oxide (Fe (NO ₃ ) ₃ ) B) 0.1 to 1% by weight of a fluorine compound, C) nitric acid (HNO ₃₎ 8 to 15% by weight, D) 2 to 5% by weight of perchloric acid (HClO ₄ ) E) from 0.1 to 5% by weight of at least one potassium salt compound selected from KNO ₃ , KCH ₃ COO and KH ₂ PO ₄ , and F) Water 69 to 87.8 wt% Based metal / aluminum-based metal double film and an indium oxide film. The etching solution composition of claim 5, wherein the fluorinated compound is at least one selected from the group consisting of NH ₄ FHF, KFHF, NaFHF, KF, and NaF. . The etchant composition of claim 5, wherein the water is deionized water. The etching solution composition of the molybdenum-based metal / aluminum-based metal double layer and indium oxide layer. The etchant composition of claim 5, further comprising at least one additive selected from the group consisting of a surfactant, a sequestering agent, and a corrosion inhibitor. The etchant composition of claim 5, wherein the indium oxide film is indium zinc oxide (IZO) or indium tin oxide (ITO). delete I) forming a molybdenum-based metal / aluminum-based metal double-layer on a substrate; II) selectively leaving a photoreactive material on the molybdenum-based metal / aluminum-based metal double layer; And III) A method for etching a molybdenum-based metal / aluminum-based metal double-layer film comprising etching the molybdenum-based metal / aluminum-based metal double-layer film using the etching liquid composition of any one of claims 5 to 9. I) forming an indium oxide film on a substrate; II) selectively leaving a photoreactive material on the indium oxide film; And III) etching the indium oxide film using the etching liquid composition according to any one of claims 5 to 9.

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