KR20150114248A - Manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

The present invention relates to a method for manufacturing an array substrate for a liquid crystal display device. The method includes the steps of: a) forming a gate electrode on a substrate; b) forming a gate insulation layer on the substrate including the gate electrode; c) forming a metal oxide film (an active layer) on the gate insulation layer; and d) forming a molybdenum metal film (a source/drain electrode) on the metal oxide film. The step d) includes a process for forming the molybdenum metal film on the metal oxide film and then selectively etching the molybdenum metal film by using an etching solution composition. The etching solution composition includes A) hydrogen peroxide (H_2O_2), B) one or more selected from organic acids and salts thereof, C) a cyclic amine compound, D) organic peroxide, and E) water as a remainder with respect to the total weight of the composition.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing an array substrate for a liquid crystal display

The present invention minimizes the attack on the lower metal oxide layer in the double film of the molybdenum metal film / metal oxide film for forming the TFT array wiring, forms a taper profile with excellent linearity with respect to the upper molybdenum metal film , An etchant composition for selectively etching only the upper molybdenum metal film, a wiring forming method using the same, and a method for manufacturing an array substrate for a liquid crystal display device.

Al, Al-Cu, Ti-W, Ti-N, etc. are proposed as metal wiring materials for semiconductor devices such as TFT-LCDs, depending on the type of substrate and required characteristics. And Al or an alloy thereof having a small electric resistance is often used for the source / drain wiring of the TFT-LCD.

However, in recent years, a single film or a multilayer of an existing Cr single film, Al or Al alloy (for example, Mp / Al-Nd double film or the like) has been used for reasons of process simplification, cost reduction, Mp / Al-Nd / Mo triple film), application of a single film made of Mo is attempted.

On the other hand, the semiconductor layer of the thin film transistor for driving the flat panel display device is mainly formed of amorphous silicon or polycrystalline silicon. The amorphous silicon is advantageous in that the film forming process is simple and the production cost is low, but the electrical reliability can not be secured , Polycrystalline silicon is very difficult to apply to a large area due to a high process temperature, and uniformity can not be secured according to the crystallization method.

However, when a semiconductor layer is formed using an oxide, a high mobility can be obtained even if the film is formed at a low temperature. Since the resistance varies depending on the content of oxygen, it is very easy to obtain desired physical properties. It attracts great attention.

For example, a thin film transistor manufacturing method in which a double film made of a Mo metal film / a metal oxide is applied to form a wiring of a TFT array is attempted. Accordingly, a technique capable of selectively etching only a molybdenum metal film without attacking the lower metal oxide layer It is necessary.

Korean Patent Laid-Open Publication No. 2010-0082094 discloses a copper film, a copper alloy film, a titanium film, a titanium film, a titanium film, a titanium film, and a titanium film including peroxides selected from sodium persulfate, potassium persulfate, Discloses an etching composition of an alloy film, a molybdenum metal film, a molybdenum alloy film, or a multilayer in which these films are laminated. Korean Patent Laid-Open Publication No. 2007-0005275 discloses an etching composition comprising phosphoric acid, nitric acid, an inorganic phosphate compound or an inorganic nitrate salt compound, H < ₂ > O), Mo, Al, Mo alloy or Al alloy.

However, the etchant composition may attack the lower metal oxide layer when the molybdenum metal film is etched in the method of manufacturing a thin film transistor using the double metal film of Mo metal / metal oxide.

Korea Patent Publication No. 2010-0082094 Korea Patent Publication No. 2007-0005275

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 manufacturing a thin film transistor, It is an object of the present invention to provide an etchant composition that minimizes attack and provides a taper profile with excellent linearity with respect to the upper molybdenum metal film.

Another object of the present invention is to provide a wiring forming method using the etchant composition and a method of manufacturing an array substrate for a liquid crystal display device.

The present invention

The present invention relates to a composition,

A) 5.0 to 25.0% by weight hydrogen peroxide (H ₂ O ₂ );

B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof;

C) 0.1 to 5.0% by weight of a cyclic amine compound;

D) from 1.0 to 5.0% by weight of organic and inorganic acids; And

E) balance of water,

Characterized in that the upper molybdenum metal film is selectively etched in the double film of the molybdenum metal film / metal oxide film.

In addition,

I) forming a metal oxide film on the substrate;

II) forming a molybdenum metal film on the metal oxide film;

III) selectively leaving a photoreactive material on the molybdenum metal film; And

IV) selectively etching said molybdenum metal film using an etchant composition,

Wherein the etchant composition comprises: A) from 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) from 1.0 to 5.0% by weight of organic and inorganic acids; And E) the remaining amount of water. The present invention also provides a method of forming a wiring of a liquid crystal display device.

Further, according to the present invention,

a) forming a gate electrode on a substrate;

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

c) forming a metal oxide film (active layer) on the gate insulating layer; And

d) forming a molybdenum metal film (source / drain electrode) on the metal oxide semiconductor layer,

The step d) includes forming a molybdenum metal film on the metal oxide semiconductor layer and selectively etching the molybdenum metal film using the etching composition,

Wherein the etchant composition comprises: A) from 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) from 1.0 to 5.0% by weight of organic and inorganic acids; And E) water of a remaining amount. The present invention also provides a method of manufacturing an array substrate for a liquid crystal display device.

In the case of using the etching composition of the present invention, it is possible to selectively etch only the upper molybdenum metal film from the double film of the molybdenum metal film / metal oxide film formed for wiring formation of the TFT array, Attack can be minimized.

In addition, when the molybdenum metal film is etched, excellent taper profile such as linearity can be formed by controlling the oxidation power, so that the wiring formation process of the TFT array can be performed very efficiently.

The present invention relates to a composition,

A) 5.0 to 25.0% by weight hydrogen peroxide (H ₂ O ₂ );

B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof;

C) 0.1 to 5.0% by weight of a cyclic amine compound;

D) from 1.0 to 5.0% by weight of organic and inorganic acids; And

E) balance of water,

Characterized in that the upper molybdenum metal film is selectively etched in the double film of molybdenum metal film / metal oxide film.

In the present invention, 'metal oxide film' is usually selected from the group consisting of AxByCzO (where A, B and C are selected from Zn, Cd, Ga, In, Sn, Hf, Zr, Ta or Ti; x, y, Wherein two or more of x, y, and z are not 0), and may be a film constituted by an oxide semiconductor layer or a film constituting an oxide semiconductor layer.

The etching ratio of the molybdenum metal film: metal oxide film of the etching solution composition of the present invention is 9.9: 0.1 to 10.0: 0.0, preferably 10.0: 0.0. When the lower metal oxide film is etched, the transistor characteristics are changed. Therefore, the etching rate as described above must be satisfied.

The A) hydrogen peroxide (H ₂ O ₂ ) acts as a peroxide for etching the upper molybdenum metal film. The A) hydrogen peroxide (H2O2) is included in an amount of 5.0 to 25.0% by weight, preferably 8.0 to 20.0% by weight, based on the total weight of the composition. If the amount is less than the above range, sufficient etching may not be performed due to insufficient etching force, and if it exceeds 25.0% by weight, process control is difficult because the etching speed is entirely accelerated.

And at least one selected from the above B) organic acids and salts thereof is suitably adjusted in pH to make the environment of the etching solution easy to etch the Mo metal film.

At least one selected from the above organic acids and their salts serves to increase the etching rate of the upper molybdenum metal film, to remove residues inevitably generated in the etching solution, and to minimize the attack on the lower metal oxide layer .

At least one selected from the above organic acids and salts thereof is contained in an amount of 1.0 to 5.0% by weight, preferably 2.0 to 4.0% by weight based on the total weight of the composition. If it is contained within the above-mentioned range, the etching rate of the upper molybdenum metal film may be lowered, so that partial unetch phenomenon or residue may occur, and the attack of the lower metal oxide may become worse. If it is contained in an amount exceeding 5.0% by weight, the upper molybdenum metal film may be excessively etched and the metal film may be lifted off from the substrate.

Specific examples of the organic acids and salts thereof include acetic acid, iminodiacetic acid, ethylenediaminetetraacetic acid, butanoic acid, citric acid, isocitric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, Sulfosuccinic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, malic acid, tartaric acid, propenoic acid and the like. Examples of salts of organic acids include potassium salts, sodium salts and ammonium salts of the above organic acids.

The C) cyclic amine compound is a component that adjusts the etching rate and forms a profile when the molybdenum film is etched. Specific examples thereof include 5-aminotetrazole, tolythriazole, benzotriazole, methylbenzotriazole, imidazole compounds, indole compounds, purine compounds, pyrazole compounds, pyridine compounds, pyrimidine compounds, A pyrrole compound, a pyrrole compound, and the like. These compounds may be used alone or in admixture of two or more.

The cyclic amine compound may be contained in an amount of 0.1 to 5% by weight, preferably 0.5 to 3% by weight based on the total weight of the composition. The molybdenum etch rate and the taper angle can be appropriately set and the side etching amount can be controlled in the above content range. If the content is less than 0.1% by weight, it is difficult to control the etching rate of molybdenum sufficiently, and an overeating angle may occur. If the content is more than 5% by weight, the etching rate of molybdenum may be lowered.

D) Organic Peroxyacid acts to control the etching rate of Mo by increasing the activity of hydrogen peroxide by controlling the pH of the etching solution, and at the same time, it serves as a secondary oxidant for Mo.

Representative examples of the organic peroxyacid include peracetic acid, perbenzoic acid, and mixtures thereof.

The amount of the organic acid is preferably 1 to 5% by weight, more preferably 1 to 3% by weight based on the total amount of the composition. If the content of the organic acid is less than 1% by weight, the pH control effect may be insufficient and Mo unetch phenomenon may occur. If the content of the organic acid exceeds 5% by weight, process control becomes difficult due to a too high etching rate .

The E) water contained in the etchant composition of the present invention is not particularly limited, but deionized water is preferred. More preferably, deionized water having a resistivity value of 18 MΩ · cm or more (that is, the degree of removal of ions in water) is preferably used. The C) water is contained in such an amount that the total weight of the composition of the present invention is 100% by weight.

In addition to the above-described components, conventional additives may be further added. Examples of the additive include a metal ion blocking agent and a corrosion inhibitor.

C) cyclic amine compounds selected from A) hydrogen peroxide (H ₂ O ₂ ), B) organic acids and salts thereof, D) organic acids and acids, and E) water used in the present invention are conventionally known methods , And it is preferable that the etchant composition of the present invention has purity for semiconductor processing.

In addition,

I) forming a metal oxide film on the substrate;

II) forming a molybdenum metal film on the metal oxide film;

III) selectively leaving a photoreactive material on the molybdenum metal film; And

IV) selectively etching said molybdenum metal film using an etchant composition,

Wherein the etchant composition comprises: A) from 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) from 1.0 to 5.0% by weight of organic and inorganic acids; And E) the remaining amount of water. ≪ IMAGE >

In the wiring forming method of the present invention, the photoreactive material is preferably a conventional photoresist material, and can be selectively left by a conventional exposure and development process.

Further, according to the present invention,

a) forming a gate electrode on a substrate;

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

c) forming a metal oxide film (active layer) on the gate insulating layer; And

d) forming a molybdenum metal film (source / drain electrode) on the metal oxide semiconductor layer,

The step d) includes forming a molybdenum metal film on the metal oxide semiconductor layer and selectively etching the molybdenum metal film using the etching composition,

Wherein the etchant composition comprises: A) from 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) from 1.0 to 5.0% by weight of organic and inorganic acids; And E) the remaining amount of water. The present invention also relates to a method of manufacturing an array substrate for a liquid crystal display device.

A manufacturing method of an array substrate for a liquid crystal display of the present invention is characterized by forming a double film of a molybdenum metal film / metal oxide film.

The array substrate for a liquid crystal display may be a thin film transistor (TFT) array substrate. The array substrate for a liquid crystal display includes a molybdenum metal film etched using the etching solution composition of the present invention.

The step of etching the molybdenum metal film with the etchant composition may be performed according to a well-known method in the art, and examples thereof include immersion and shedding. The temperature in the etching process is generally 20 to 50 ° C, preferably 30 to 45 ° C, and the optimum process temperature is determined as necessary depending on other process conditions and factors.

The time for etching the molybdenum metal film with the etchant composition may vary depending on the temperature and the thickness of the thin film, but is usually several seconds to several tens of minutes.

The present invention also provides an array substrate for a liquid crystal display comprising source and drain electrodes etched using the etchant composition.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following embodiments are for further illustrating the present invention, and the scope of the present invention will be determined by the technical idea of the following claims.

Example  1 to 4: Etchant  Preparation of composition

Each component was mixed according to the composition shown in the following Table 1 to prepare the etching solution compositions of Examples 1 to 4 and Comparative Examples 1 and 2.

Unit: wt% H ₂ O ₂ Ammonium acetate 5-Aminotetrazole And acetic acid DIW molybdenum
Etch characteristics Metal oxide film
Attack Example 1 15 3.0 1.0 2 Balance ◎ No Example 2 15 5.0 5.0 1.0 Balance ◎ No Example 3 15 3.0 1.0 5 Balance ◎ No Example 4 15 3.0 1.0 1.0 Balance ◎ No Comparative Example 1 3 3.0 5.0 1.0 Balance × No Comparative Example 2 15 3.0 5 10.0 Balance × No Comparative Example 3 15 3.0 5 - Balance × No Comparative Example 4 40 1.0 - 1.0 Balance × Yes

⊚: excellent (CD Skew ≤ 1 μm, Taper Angle: 40 ° to 60 °)

Good: Excellent (1 탆 <CD Skew ≤ 1.5 탆, Taper Angle: 30 캜 to 60 캜)

?: Good (1.5 탆 <CD Skew ≤ 2 탆, Taper Angle: 20 째 to 60 째)

X: Bad (metal film disappearance and residue formation)

Test Example : Etchant  Evaluation of composition characteristics

An IGZO film was stacked as a metal oxide film on the lower side using the etching solution compositions of Examples 1 to 4 and Comparative Examples 1 and 2 and a glass substrate on which a molybdenum single film as a molybdenum metal film was stacked on the metal oxide film was subjected to an etching process Respectively. (ETCHER (TFT), manufactured by SEMES) was used as the etchant, and the temperature of the etchant composition was set to about 40 ° C during the etching process. However, the optimum temperature was determined according to other process conditions and other factors can be changed. The etching time may vary depending on the etching temperature, but usually proceeds to about 100 seconds. The images of the molybdenum metal film and the metal oxide film that were etched in the etching process were examined using an SEM (product name: S-4700, manufactured by Hitachi).

As shown in Table 1, all of the etching solutions of Examples 1 to 4 exhibited good etching characteristics and no residue was formed. In particular, it was confirmed that the etchant of Example 3 had a high content of organic acid and acid, thereby increasing the etching rate of the metal film of molybdenum.

The etching solution of Comparative Example 1 had a hydrogen peroxide content that was too low as described above, so that the molybdenum metal film was not partially etched and a residue form was present. In the etching solution of Comparative Example 2, the etching property of the upper molybdenum metal film was excellent, Organic and acid were added in excess and showed wire loss due to overeating angle. In the case of Comparative Example 3, a residual film of molybdenum was generated without organic and acid components. In the case of Comparative Example 4, a metal oxide film attack occurred due to excessive inclusion of a strong oxidizing power.

Claims (11)

a) forming a gate electrode on a substrate;
b) forming a gate insulating layer on the substrate including the gate electrode;
c) forming a metal oxide film (active layer) on the gate insulating layer; And
d) forming a molybdenum metal film (source / drain electrode) on the metal oxide film,
The step d) includes forming a molybdenum metal film on the metal oxide film and selectively etching the molybdenum metal film using the etching composition,
Wherein the etchant composition comprises: A) from 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) from 1.0 to 5.0% by weight of organic and inorganic acids; And E) the remaining amount of water. The method according to claim 1,
Wherein the array substrate for a liquid crystal display is a thin film transistor (TFT) array substrate. The method according to claim 1,
X, y, and z? 0, wherein x, y, z, and z are each independently selected from the group consisting of Zn, Cd, Ga, In, Sn, Hf, Zr, Ta, Wherein at least two of the oxides are not 0). &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt; With respect to the total weight of the composition,
A) 5.0 to 25.0% by weight hydrogen peroxide (H ₂ O ₂ );
B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof;
C) 0.1 to 5.0% by weight of a cyclic amine compound;
D) from 1.0 to 5.0% by weight of organic and inorganic acids; And
E) balance of water,
Wherein the upper molybdenum metal film is selectively etched in the double film of molybdenum metal film / metal oxide film. The method of claim 4,
Wherein the etchant composition has an etch rate of molybdenum metal film: metal oxide film of 9.9: 0.1 to 10.0: 0.0. [5] The method according to claim 4, wherein at least one selected from the group consisting of B) organic acids and salts thereof is at least one selected from the group consisting of acetic acid, iminodiacetic acid, ethylenediaminetetraacetic acid, butanoic acid, citric acid, isocitric acid, formic acid, gluconic acid, From the group consisting of oxalic acid, pentanoic acid, sulfobenzoic acid, succinic acid, sulfosuccinic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, malic acid, tartaric acid, propenoic acid and potassium, sodium and ammonium salts thereof &Lt; / RTI &gt; The method of claim 4,
The C) cyclic amine compound may be at least one compound selected from the group consisting of 5-aminotetrazole, tolithriazole, benzotriazole, methylbenzotriazole, imidazole compounds, indole compounds, purine compounds, pyrazole compounds, pyridine compounds, A pyrrole-based compound, a pyrrolidine-based compound, and a pyrroline-based compound. The method of claim 4,
Wherein the D) organic and inorganic acid are peracetic acid, perbenzoic acid or a mixture thereof. 5. The etchant composition of claim 4, wherein the etchant composition further comprises a sequestering agent or a corrosion inhibitor. I) forming a metal oxide film on the substrate;
II) forming a molybdenum metal film on the metal oxide film;
III) selectively leaving a photoreactive material on the molybdenum metal film; And
IV) selectively etching said molybdenum metal film using an etchant composition,
Wherein the etchant composition comprises: A) from 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) from 1.0 to 5.0% by weight of organic and inorganic acids; And E) the remaining amount of water. An array substrate for a liquid crystal display, comprising source and drain electrodes etched using the etchant composition of claim 4.