KR102269327B1 - Etchant composition and manufacturing method of an array for liquid crystal display - Google Patents

Abstract

The present invention relates to an etchant composition and a method for manufacturing an array substrate for a liquid crystal display. The etchant composition of the present invention can etch a copper-based metal film in a batch when manufacturing an array substrate for a liquid crystal display, and is characterized in that the etch profile is excellent and the amount of change in the taper angle is within ±5°.

Description

Etchant composition and method of manufacturing an array substrate for a liquid crystal display {ETCHANT COMPOSITION AND MANUFACTURING METHOD OF AN ARRAY FOR LIQUID CRYSTAL DISPLAY}

The present invention relates to an etchant composition and a method for manufacturing an array substrate for a liquid crystal display.

The process of forming a metal wiring on a substrate in a semiconductor device is usually composed of a metal film forming process by sputtering, etc., a photoresist forming process in a selective area by photoresist application, exposure and development, and an etching process. , and cleaning processes before and after individual unit processes. Such an etching process refers to a process of leaving a metal film in a selective region using a photoresist as a mask, and typically dry etching using plasma or wet etching using an etchant composition is used.

In such a semiconductor device, the resistance of metal wiring has recently emerged as a major concern. This is because resistance is a major factor that causes RC signal delay, and in particular, in the case of TFT-LCD (thin film transistor-liquid crystal display), increasing the panel size and realizing high resolution are key to technology development. Therefore, in order to realize the reduction of the RC signal delay, which is essential for the enlargement of the TFT-LCD, it is essential to develop a low-resistance material. Therefore, chromium (Cr, resistivity: 12.7 × 10 ^-8 Ωm), molybdenum (Mo, resistivity: 5 × 10 ^-8 Ωm), aluminum (Al, resistivity: 2.65 × 10 ^-8 Ωm), which have been mainly used in the prior art, and these It is difficult to use the alloy for gate and data wiring used in large TFT LCDs.

Under such a background, interest in a copper-based metal film such as a copper film and a copper molybdenum film and an etchant composition thereof as a new low-resistance metal film is high, and research on this is being actively conducted. For example, in Korean Patent Application Laid-Open No. 2010-0090538, hydrogen peroxide, an organic acid, a phosphate compound, a water-soluble cyclic amine compound, a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, a fluorine-containing compound, a polyalcohol type surfactant, and water are included. An etchant composition for a copper-based metal film is presented. However, in the case of the etchant, there is a limit in maintaining the taper angle according to the change in the number of treatment sheets during etching of the thick metal layer.

Republic of Korea Patent Publication No. 2010-0090538

An object of the present invention is to provide an etchant composition having an excellent etch profile and a change in taper angle within ±5°.

The present invention includes hydrogen peroxide, a fluorine compound, an azole compound, a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, tartaric acid, a phosphate compound, a polyalcohol-type surfactant, a sulfate compound, and water, wherein the sulfate compound is the total content of the etchant composition It provides an etchant composition for a copper-based metal film that is contained in an amount of 0.01 to 5% by weight with respect to it.

In one embodiment of the present invention, the etchant composition contains 5 to 30% by weight of hydrogen peroxide, 0.01 to 5% by weight of a fluorine compound, 0.1 to 5% by weight of an azole compound, 0.5 to 5% by weight of a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, 0.1 to 5% by weight of tartaric acid, 0.1 to 5% by weight of a phosphate compound, 0.001 to 5% by weight of a polyalcohol-type surfactant, 0.01 to 5% by weight of a sulfate compound, and the remaining amount of water.

In another embodiment, the fluorine compound may be at least one selected from the group consisting _{of HF, NaF, NH 4} F, NH ₄ BF ₄ , NH ₄ FHF, KF, KHF ₂ , AlF ₃ and HBF _{4 .}

In another embodiment, the azole compound is a triazole-based compound, an aminotetrazole-based compound, a pyrrole-based compound, a pyrazol-based compound, an imidazole-based compound, and a tetra Composed of a tetrazole-based compound, a pentaazole-based compound, an oxazole-based compound, an isoxazole-based compound, a diazole-based compound, and an isodiazole-based compound It is at least one selected from the group, and the etchant composition may include a triazole-based compound as an azole compound.

In another embodiment, the water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is at least one selected from the group consisting of alanine, aminobutyric acid, glutamic acid, glycine, iminodiacetic acid, nitrilotriacetic acid and sarcosine.

In another embodiment, the phosphate compound may be at least one selected from the group consisting of sodium phosphate, potassium phosphate and ammonium sulfate.

In another embodiment, the polyhydric alcohol-type surfactant may be at least one selected from the group consisting of glycerol, triethylene glycol, and polyethylene glycol.

In another embodiment, the sulfate compound may be at least one selected from the group consisting of sodium sulfate, potassium sulfate, ammonium sulfate, and potassium hydrogen sulfate. .

In another embodiment, the copper-based metal film is a single film of copper or a copper alloy; Alternatively, it may be a multilayer film including one or more films selected from the group consisting of a molybdenum film, a molybdenum alloy film, a titanium film, and a titanium alloy film, and one or more films selected from a copper film and a copper alloy film.

In addition, the present invention includes the steps of: a) forming a gate wiring on a substrate; b) forming a gate insulating layer on a substrate including the gate wiring; c) forming a semiconductor layer on the gate insulating layer; A method of manufacturing an array substrate for a liquid crystal display, comprising: d) forming source and drain electrodes on the semiconductor layer; and e) forming a pixel electrode connected to the drain electrode. At least one of step d) includes laminating a metal layer including copper or a copper alloy on the substrate, and etching using an etchant composition, wherein the etchant composition is hydrogen peroxide, a fluorine compound, an azole compound, A water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, tartaric acid, a phosphate compound, a polyalcohol-type surfactant, a sulfate compound, and water, wherein the sulfate compound is included in an amount of 0.01 to 5% by weight based on the total weight of the composition It provides a method of manufacturing an array substrate for a liquid crystal display.

In one embodiment, the array substrate for a liquid crystal display may be a thin film transistor (TFT) array substrate.

In addition, the present invention provides an array substrate for a liquid crystal display including at least one of a gate wiring, a source electrode, and a drain electrode etched using the etchant composition.

The etchant composition of the present invention can etch a copper-based metal film in a batch when manufacturing an array substrate for a liquid crystal display, and is characterized in that the etch profile is excellent and the amount of change in the taper angle is within ±5°.

The present invention relates to an etchant composition and a method for manufacturing an array substrate for a liquid crystal display.

As the etchant composition of the present invention contains a certain amount of the sulfate compound, it is characterized in that the etch profile is excellent and the taper angle is constantly maintained.

Hereinafter, the present invention will be described in detail.

The present invention includes hydrogen peroxide, a fluorine compound, an azole compound, a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, tartaric acid, a phosphate compound, a polyalcohol-type surfactant, a sulfate compound, and water, wherein the sulfate compound is the total content of the etchant composition It provides an etchant composition for a copper-based metal film that is contained in an amount of 0.01 to 5% by weight with respect to it.

In the present invention, the copper-based metal film includes copper as a component of the film, and includes a single film of copper or a copper alloy; and a multilayer film including one or more films selected from a copper film and a copper alloy film and one or more films selected from the group consisting of a molybdenum film, a molybdenum alloy film, a titanium film, and a titanium alloy film.

In addition, the alloy film is a concept including a nitride film or an oxide film.

Examples of the multilayer film include a copper/molybdenum film, a copper/molybdenum alloy film, a copper alloy/molybdenum alloy film, a double film such as a copper/titanium film, or a triple film. The copper / molybdenum film means comprising a molybdenum layer and a copper layer formed on the molybdenum layer, and the copper / molybdenum alloy film includes a molybdenum alloy layer and a copper layer formed on the molybdenum alloy layer. The alloy/molybdenum alloy film means including a molybdenum alloy layer and a copper alloy layer formed on the molybdenum alloy layer, and the copper/titanium film includes a titanium layer and a copper layer formed on the titanium layer.

The molybdenum alloy layer includes, for example, one or more metals selected from the group consisting of titanium (Ti), tantalum (Ta), chromium (Cr), nickel (Ni), neodymium (Nd), and indium (In). It means a layer made of an alloy of molybdenum.

In particular, the etchant composition of the present invention can be preferably applied to a multi-layer film consisting of a copper or copper alloy film and a molybdenum or molybdenum alloy film.

In the present invention, the thickness of the thick (Cu) metal layer may be 5000 Å or more. In the case of the thick film, the conventionally known etchant has a slow corrosion rate and increases the process time. Accordingly, it is not applicable when the thickness of the thick metal layer is 5000 Å or more, but the etchant composition of the present invention has a thickness of 5000 Å. It is characteristic that it can be applied even if it is more than Å.

Hereinafter, the configuration of the etchant composition of the present invention will be described in detail.

hydrogen peroxide

_{Hydrogen peroxide (H 2} O ₂ ) contained in the etchant composition of the present invention is a copper molybdenum film or a molybdenum alloy layer including a molybdenum layer and a copper layer formed on the molybdenum layer and a copper layer formed on the molybdenum alloy layer. It is a main oxidizing agent that affects the etching of a copper-based metal film, characterized in that it is a copper molybdenum alloy film, and the hydrogen peroxide (H ₂ O ₂ ) is 5 to 30.0 wt%, preferably 17 to 25.0 wt%, based on the total weight of the composition included in %. When included in less than the above range, sufficient etching may not be achieved due to insufficient etching power of the copper-based metal film and the molybdenum alloy film, and when included in excess of 30 wt %, the thermal stability due to the increase in copper ions is greatly reduced. can

fluorine compounds

The fluorine compound included in the etchant composition of the present invention refers to a compound capable of dissociating in water to produce fluorine ions. The fluorine compound is an auxiliary oxidizing agent that affects the etching rate of the molybdenum alloy film, and controls the etching rate of the molybdenum alloy film.

The fluorine compound is included in an amount of 0.01 to 5.0% by weight, preferably 0.1 to 3.0% by weight, based on the total weight of the composition. When included in less than the above range, the etching rate of the molybdenum alloy film may be slow. When included in excess of the above-mentioned range, the etching performance of the molybdenum alloy film is improved, but since the etching rate is overall faster, the undercut phenomenon or the etching damage of the lower layer (n+ a-Si:H, a-Si:G) may appear significantly. have.

The fluorine compound is not particularly limited as long as it is used in the art. However, the fluorine compound is preferably selected from the group consisting of HF, NaF, NH ₄ F, NH ₄ BF ₄ , NH ₄ FHF, KF, KHF ₂ , AlF ₃ and HBF ₄ , more preferably _{NH 4} F ₂ Do.

azole compounds

The azole compound included in the etchant composition of the present invention controls the etching rate of the copper-based metal film and reduces the CD loss of the pattern, thereby increasing the process margin.

The azole compound is included in an amount of 0.1 to 5% by weight, preferably 0.5 to 1.5% by weight, based on the total weight of the composition. When the azole compound is included in an amount of less than 0.1 wt %, the etching rate is fast and cydilos may be generated too large. When the azole compound is included in an amount exceeding 5 wt %, the etching rate of the copper-based metal film becomes too slow, so that the etching rate of the metal oxide film is relatively reduced. Since the etching rate is increased, an undercut may occur.

The azole compound may be selected from two or more compounds essentially including a triazole-based compound. If the azole compound does not include a triazole-based compound in the composition, it is impossible to control the etching profile variation according to the number of treatment sheets when the thick copper metal layer is etched, thereby reducing the process margin.

The azole compound includes, for example, a triazole-based compound, an aminotetrazole-based compound, a pyrrole-based compound, a pyrazol-based compound, an imidazole-based compound, and a tetrazole ( tetrazole-based compounds, pentaazole-based compounds, oxazole-based compounds, isoxazole-based compounds, diazole-based compounds, and isodiazole-based compounds; and may be selected from two or more compounds essentially containing a triazole-based compound.

The triazole-based compound may be, for example, triazole.

within one molecule nitrogen atom and Water-soluble compound having a carboxyl group

The water-soluble compound having a nitrogen atom and a carboxyl group in one molecule included in the etchant composition of the present invention prevents the self-decomposition reaction of hydrogen peroxide that may occur during storage of the etchant composition, and the etching characteristics change when a large number of substrates are etched. to prevent

In general, in the case of an etchant composition using hydrogen peroxide solution, the hydrogen peroxide solution self-decomposes during storage, so the storage period is not long and the container has a risk of explosion. However, when a water-soluble compound having a nitrogen atom and a carboxyl group is included in one molecule, the decomposition rate of the hydrogen peroxide solution is reduced by nearly 10 times, which is advantageous for securing storage period and stability. In particular, in the case of a copper layer, when a large amount of copper ions remain in the etchant composition, a passivation film is formed and is oxidized to black, and there are many cases where it is no longer etched. However, when the compound is added, this phenomenon can be prevented. .

The content of the water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is included in an amount of 0.5 to 5% by weight, particularly preferably in a range of 1 to 3% by weight. When the content of the water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is less than 0.5 wt %, a passivation film is formed after etching a large amount of substrates (about 500 sheets), so it may be difficult to obtain a sufficient process margin. In addition, when the content of the water-soluble compound having a nitrogen atom and a carboxyl group in one molecule exceeds 5% by weight, the etching rate of molybdenum or molybdenum alloy is slowed, so that in the case of a copper molybdenum film or a copper molybdenum alloy film, a molybdenum or molybdenum alloy film residue problem may occur.

The water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is alanine, aminobutyric acid, glutamic acid, glycine, iminodiacetic acid, nitrilotriacetic acid ) and sarcosine, and the like, and iminodiacetic acid is most preferred.

tartaric acid

Tartaric acid contained in the etchant composition of the present invention serves to control the amount of side etching by controlling the lateral etching rate when etching the thick copper metal layer. If tartaric acid is not present in the etchant composition of the present invention, defects may occur due to a fast lateral etching rate.

The content of the tartaric acid is included in the composition in an amount of 0.1 to 5% by weight, particularly preferably in the range of 0.3 to 3% by weight, based on the total weight of the composition. When the content of the tartric acid is less than 0.1% by weight, the etch profile may be poor due to a fast lateral etching rate. When the amount of tartaric acid exceeds 5% by weight, there may be a problem in that the lateral etching rate of the copper or copper alloy film or the molybdenum alloy film is too slow.

phosphate compound

The phosphate compound included in the etchant composition of the present invention is a component that makes the etch profile good. If the phosphate compound is not present in the etchant composition of the present invention, partial over-erosion may occur.

The content of the phosphate compound is included in the composition in an amount of 0.1 to 5% by weight, particularly preferably in the range of 0.5 to 3% by weight, based on the total weight of the composition. When the amount of the phosphate compound is less than 0.1% by weight, the etch profile may be poor due to partial over-erosion. When the phosphate compound exceeds 5 wt%, there may be problems in that the corrosion rate of the copper or copper alloy film is reduced and the etching rate of the molybdenum or molybdenum alloy film is slowed down.

The phosphate compound is not particularly limited as long as it is selected from salts in which one or two hydrogens in phosphoric acid are substituted with alkali metals or alkaline earth metals, but monobasic ammonium phosphate (ammonium phosphate monobasic), monobasic sodium phosphate (sodium phosphate monobasic), and potassium phosphate monobasic, ammonium phosphate dibasic, sodium phosphate dibasic, and potassium phosphate dibasic. And among them, ammonium phosphate dibasic is most preferred.

polyhydric alcohol Surfactants

The polyalcohol-type surfactant included in the etchant composition of the present invention serves to increase the uniformity of the etching by reducing the surface tension. In addition, the polyalcohol-type surfactant suppresses the activity of copper ions by surrounding copper ions dissolved in the etchant after etching the copper film, thereby suppressing the decomposition reaction of hydrogen peroxide. If the activity of copper ions is lowered in this way, the process can be performed stably while using the etchant.

The content of the polyhydric alcohol-type surfactant is included in the range of 0.001 to 5% by weight, particularly preferably in the range of 0.1 to 3% by weight, based on the total weight of the composition. When the content of the polyalcohol-type surfactant is less than 0.001 wt %, there may be problems in that the etching uniformity is lowered and the decomposition of hydrogen peroxide is accelerated. If the content of the polyhydric alcohol-type surfactant exceeds 5% by weight, a lot of foam may be generated.

The polyhydric alcohol-type surfactant may include glycerol, triethylene glycol, and polyethylene glycol. And among them, triethylene glycol is preferable.

sulfate compound

The sulfate compound included in the etchant composition of the present invention serves to constantly maintain the taper angle, which is the angle of the metal film, which changes as the number of treatments increases. If the taper angle is kept constant in this way, deposition defects that may occur during the subsequent process are reduced and the process can be performed stably.

The content of the sulfate compound is included in the range of 0.01 to 5.0% by weight, particularly preferably in the range of 0.1 to 3.0% by weight, based on the total weight of the composition. If the content of the sulfate compound is less than the above range, there may be a problem in that the amount of change in the taper angle increases as the number of treated sheets increases. If the content of the sulfate compound is greater than or equal to the above range, the etching rate of the copper film by sulfate may be increased, and thus a stable process may not be performed.

The sulfate compound is one selected from sodium sulfate (Sodium Sulfate), potassium sulfide (Potassium Sulfate), ammonium sulfide (Ammonium Sulfate), and potassium hydrogen sulfate (Potassium Hydrogen Sulfate), characterized in that it is a mixture of two or more.

The remaining amount of water included in the etchant composition of the present invention is included so that the total weight of the composition is 100% by weight. The water is not particularly limited, but deionized water is preferably used. In addition, as the water, it is more preferable to use deionized water having a specific resistance value of 18 MΩ·cm or more, which shows the degree of removal of ions in the water.

In addition, the present invention includes the steps of: a) forming a gate wiring on a substrate; b) forming a gate insulating layer on a substrate including the gate wiring; c) forming a semiconductor layer on the gate insulating layer; A method of manufacturing an array substrate for a liquid crystal display, comprising: d) forming source and drain electrodes on the semiconductor layer; and e) forming a pixel electrode connected to the drain electrode. At least one of step d) includes laminating a metal layer including copper or a copper alloy on the substrate, and etching using an etchant composition, wherein the etchant composition is hydrogen peroxide, a fluorine compound, an azole compound, A water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, tartaric acid, a phosphate compound, a polyalcohol-type surfactant, a sulfate compound, and water, wherein the sulfate compound is included in an amount of 0.01 to 5% by weight based on the total weight of the composition It provides a method of manufacturing an array substrate for a liquid crystal display.

The array substrate for the liquid crystal display may be a thin film transistor (TFT) array substrate.

In addition, the present invention provides an array substrate for a liquid crystal display including at least one of a gate wiring, a source electrode, and a drain electrode etched using the etchant composition.

Hereinafter, the present invention will be described in more detail using Examples, Comparative Examples and Experimental Examples. However, the following Examples, Comparative Examples and Experimental Examples are provided to illustrate the present invention, and the present invention is not limited by the following Examples, Comparative Examples and Experimental Examples and may be variously modified and changed.

Example 1-2 and comparative example 1-3. etchant Preparation of the composition

180 kg of an etchant composition was prepared with the composition and content (% by weight) shown in Table 1 below.

division H ₂ O ₂ ABF 5-ATZ triazole IDA tartaric acid NHP TEG KHSO ₄ Example 1 20 0.10 0.40 0.20 2.0 0.5 0.5 1.5 1.0 Example 2 17 0.20 0.30 0.30 2.2 1.0 1.0 1.5 0.5 Comparative Example 1 20 0.10 0.40 0.20 2.0 0.5 0.5 1.5 - Comparative Example 2 20 0.10 0.40 0.20 2.0 0.5 0.5 1.5 0.005 Comparative Example 3 20 0.10 0.40 0.20 2.0 0.5 0.5 1.5 7.0

* ABF: ammomium bifluoride

* 5-ATZ: 5-aminotetrazole

* IDA: iminodiacetic acid

* NHP: sodium phosphate monobasic

* TEG: triethylene glycol

Experimental example . Etching Characteristics evaluation

The etching process was performed using the etchant compositions of Examples 1 to 2 and Comparative Examples 1 to 3, respectively. Experimental equipment (model name: ETCHER (TFT), SEMES Co., Ltd.) of the spray-type etching method was used, and the temperature of the etchant composition during the etching process was about 33°C. The etching time may vary depending on the etching temperature, but in the LCD etching process, it was usually performed for about 30 to 80 seconds. The profile of the copper-based metal film etched in the etching process was inspected using a cross-sectional SEM (manufactured by Hitachi, model name S-4700), and the results are shown in Table 2 below. For the copper-based metal film used in the etching process, a Cu/Mo-Ti 5000/300 Å thin film substrate was used.

The amount of change in taper angle (°) according to Cu concentration was measured. As for the taper angle, if the angle of the metal film formed after etching, that is, if the amount of change in the taper angle according to the number of treatment is large, it is desirable to minimize the amount of change in the taper angle because it causes deposition defects during the subsequent process and a stable process cannot be performed. In this evaluation, when the condition that the change in taper angle according to the number of treatment sheets is within ±5° is satisfied, the etchant composition can be continued to be used in the etching process and the experiment was conducted, and the results are shown in Table 2.

division etch profile Change of taper angle according to the number of processed sheets (°)
(Cu 300~6000ppm) Example 1 ○ 3 Example 2 ○ 3 Comparative Example 1 ○ 10 Comparative Example 2 ○ 9 Comparative Example 3 △ 6

<Etch Profile>

○: good

△: Normal

Х: bad

Unetch: Unetched

As shown in Table 2, Examples 1 and 2 showed an excellent etch profile compared to Comparative Examples 1 to 3, and showed a result within 5 of the change in taper angle (°) according to the number of treatment sheets.

Claims (12)

hydrogen peroxide, fluorine compounds, azole compounds, water-soluble compounds having a nitrogen atom and a carboxyl group in one molecule, tartaric acid, phosphate compounds, polyalcohol-type surfactants, sulfate compounds, and water;
The sulfate compound is potassium hydrogen sulfate (Potassium Hydrogen Sulfate), which is included in 0.01 to 5% by weight based on the total content of the etchant composition, the etchant composition of the copper-based metal film. The method according to claim 1,
5 to 30% by weight of hydrogen peroxide;
0.01 to 5 wt% of a fluorine compound,
0.1 to 5% by weight of an azole compound;
0.5 to 5 wt% of a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule;
0.1 to 5% by weight of tartaric acid;
0.1 to 5% by weight of a phosphate compound,
0.001 to 5% by weight of a polyhydric alcohol-type surfactant;
0.01 to 5% by weight of a sulfate compound, and
An etchant composition for a copper-based metal film containing the remaining amount of water. The method according to claim 1,
The fluorine compound is at least one selected from the group consisting of HF, NaF, NH ₄ F, NH ₄ BF ₄ , NH ₄ FHF, KF, KHF ₂ , AlF ₃ and HBF ₄ , the etchant composition of a copper-based metal film. The method according to claim 1,
The azole compound is a triazole-based compound, an aminotetrazole-based compound, a pyrrole-based compound, a pyrazol-based compound, an imidazole-based compound, and a tetrazole-based compound. 1 selected from the group consisting of a compound, a pentazole-based compound, an oxazole-based compound, an isoxazole-based compound, a diazole-based compound, and an isothiazole-based compound more than a species,
The etchant composition comprises a triazole-based compound as an azole compound, the copper-based metal film etchant composition. The method according to claim 1,
The water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is at least one selected from the group consisting of alanine, aminobutyric acid, glutamic acid, glycine, iminodiacetic acid, nitrilotriacetic acid and sarcosine. . The method according to claim 1,
The phosphate compound is at least one selected from the group consisting of sodium phosphate, potassium phosphate and ammonium sulfate. The method according to claim 1,
The polyalcohol-type surfactant is at least one selected from the group consisting of glycerol, triethylene glycol, and polyethylene glycol. delete The method according to claim 1,
The copper-based metal film may include a single film of copper or a copper alloy; or
Molybdenum film, a molybdenum alloy film, a copper-based metal film etchant composition comprising at least one film selected from the group consisting of a titanium film and a titanium alloy film and at least one film selected from a copper film and a copper alloy film. 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) a method of manufacturing an array substrate for a liquid crystal display comprising the step of forming a pixel electrode connected to the drain electrode,
At least one of step a) or step d) comprises depositing a metal layer containing copper or a copper alloy on the substrate, and etching using an etchant composition,
The etchant composition is a method of manufacturing an array substrate for a liquid crystal display, characterized in that the etchant composition of claim 1. 11. The method of claim 10,
The method of manufacturing an array substrate for a liquid crystal display, characterized in that the array substrate for the liquid crystal display is a thin film transistor (TFT) array substrate. An array substrate for a liquid crystal display comprising at least one of a gate wiring, a source electrode, and a drain electrode etched using the etchant composition of claim 1 .