KR20100090535A - Manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

PURPOSE: A method of manufacturing array substrate for liquid display device is provided not to remain residue of copper metal film which taper profile of excellent linearity is formed. CONSTITUTION: A copper-system metal film is formed on a substrate. The copper-system metal film is etched as a etchant composition. A gate wire is formed. A copper-system metal film is formed. The copper-system metal file is etched as an etchant composition. A source and a drain electrode are formed.

Description

Manufacturing method of array substrate for liquid crystal display device {MANUFACTURING METHOD OF AN ARRAY SUBSTRATE FOR LIQUID CRYSTAL DISPLAY}

The present invention relates to a method of manufacturing an array substrate for a liquid crystal display device, an etching liquid composition of a copper metal film, and an etching method of a copper metal film using the etching liquid composition.

The process of forming the metal wiring on the substrate in the semiconductor device is generally composed of a metal film forming process by sputtering or the like, a photoresist forming process in a selective region by photoresist coating, exposure and development, and an etching process. And washing processes before and after individual unit processes. The etching process refers to a process of leaving a metal film in a selective region using a photoresist as a mask, and typically, a dry etching using a plasma or the like and a wet etching using an etching liquid composition are used.

In such semiconductor devices, the resistance of metallization has recently emerged as a major concern. Because resistance is a major factor in causing RC signal delay, especially in the case of TFT-LCD (thin film transistor-liquid crystal display), increasing 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 large-sized TFT-LCD, it is necessary to develop a material of low resistance. Therefore, chromium (Cr, specific resistance: 12.7 x 10 < -8 > m), molybdenum (Mo, specific resistance: 5 x 10 < -8 > m), aluminum (Al, specific resistance: 2.65 x 10 < -8 > It is difficult to use the gate and data wiring used in the large-size TFT LCD.

Under such a background, there is high interest in copper-based metal films such as copper films and copper molybdenum films and etching liquid compositions thereof as new low resistance metal films. However, in the case of the etching liquid composition for the copper-based metal film is currently used in various types, the situation does not meet the performance required by the user.

An object of the present invention is to provide an etching liquid composition of the copper-based metal film in which the residue of the copper-based metal film in which a tapered profile excellent in linearity is formed during etching of the copper-based metal film does not remain. In addition, an object of the present invention is to provide an etchant composition of a copper-based metal film capable of batch etching gate electrodes and gate wirings, source / drain electrodes and data wirings. It is also an object of the present invention to provide an etching method of a copper-based metal film using the etching solution composition and a method of manufacturing an array substrate for a liquid crystal display device.

The present invention provides a composition comprising: A) 5 to 25% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 0.1-5% by weight sulfuric acid; C) 0.01 to 1.0 wt% of a fluorine-containing compound; D) 0.1-5% by weight of azole compound; E) 0.1 to 5% by weight of imidazole compounds; F) It provides the etching liquid composition of the copper metal film containing residual amount of water.

In addition, the present invention comprises the steps of (I) forming a copper-based metal film on the substrate; II) selectively leaving a photoreactive material on the copper-based metal film; And iii) etching the copper-based metal film using the etchant composition.

In addition, the present invention comprises the steps of 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, wherein the step a) includes forming a copper-based metal film on the substrate and forming the copper-based metal film into the etching solution. And etching the composition to form a gate wiring, wherein step d) includes forming a copper-based metal film and etching the copper-based metal film with the etchant composition to form source and drain electrodes. A method of manufacturing an array substrate for a liquid crystal display device is provided.

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

The etchant composition according to the present invention can implement a taper profile excellent in linearity when etching the copper-based metal film. In addition, when etching the copper-based metal film with the etchant composition according to the present invention, no residue occurs, so that problems such as electrical shorts, wiring defects, and luminance decrease do not occur.

In addition, when manufacturing an array substrate for a liquid crystal display device using the etchant composition according to the present invention, it is possible to collectively etch the gate electrode and gate wiring, the source / drain electrode and the data wiring, so that the process is very simplified to maximize the process yield have.

Furthermore, when the etchant composition according to the present invention is used for etching low-resistance copper or copper alloy wirings, a large screen, high brightness circuit can be realized, and an environmentally friendly array substrate for a liquid crystal display device can be manufactured.

The present invention relates to an etching liquid composition of a copper-based metal film comprising A) hydrogen peroxide (H ₂ O ₂ ), B) sulfuric acid, C) fluorine-containing compound, D) azole compound, E) imidazole compound, and F) water. will be.

In the present invention, the copper-based metal film includes copper as a constituent of the film, and is a concept including a multilayer film such as a single film and a double film. For example, a copper molybdenum film, a copper molybdenum alloy film, etc. are contained as a single film | membrane of copper or a copper alloy, and a multilayer film. The copper molybdenum film is meant to include a molybdenum layer and a copper layer formed on the molybdenum layer, and the copper molybdenum alloy film means a copper layer formed on the molybdenum alloy layer and the molybdenum alloy layer. The molybdenum alloy layer may include at least one selected from the group consisting of titanium (Ti), tantalum (Ta), chromium (Cr), nickel (Ni), neodymium (Nd), indium (In), and the like. Means alloy.

A) hydrogen peroxide (H ₂ O ₂ ) included in the etchant composition of the present invention is the main component for etching the copper-based metal film, the content is 5 to 25% by weight relative to the total weight of the composition. If the content of hydrogen peroxide is less than 5% by weight, the copper-based metal cannot be etched or the etching rate becomes very slow. In addition, when the content of hydrogen peroxide of A) exceeds 25% by weight, it is difficult to control the process because the etching rate is faster overall.

B) sulfuric acid contained in the etchant composition of the present invention serves to create an environment in which the copper-based metal film can be etched by adjusting the pH, and lowers the pH to inhibit hydrogen peroxide decomposition. The content of sulfuric acid B) is 0.1 to 5% by weight based on the total weight of the composition. When the content of sulfuric acid B is less than 0.1% by weight, the effect of adjusting the pH is insufficient, so that the etching rate of copper is too low and hydrogen peroxide decomposition is accelerated. B) When the sulfuric acid content is more than 5.0% by weight, the etching speed of copper is increased and the etching rate of molybdenum or molybdenum alloy is slowed, so that CD Loss is increased and residues of molybdenum or molybdenum alloy may occur. Will become large.

C) fluorine-containing compound included in the etchant composition of the present invention means a compound capable of dissociating in water to give F ions. The C) fluorine-containing compound serves to remove residues that are inevitably generated in a solution for simultaneously etching a copper film and a molybdenum film. The content of the C) fluorine-containing compound is 0.01 to 1.0% by weight based on the total weight of the composition. When the content of the C) fluorine-containing compound is less than 0.01% by weight, an etching residue may occur. When the content of the C) fluorine-containing compound exceeds 1.0% by weight, there is a disadvantage in that the glass substrate etching rate is greatly generated.

The C) fluorine-containing compound is a material used in the art, and is not particularly limited as long as it is a compound capable of dissociating into fluorine ions or polyatomic fluoride ions in solution, ammonium fluoride (NH ₄ F), sodium fluoride (sodium fluoride: NaF), potassium fluoride (KF), ammonium bifluoride (NH ₄ FHF), sodium bifluoride (NaFHF), and potassium bifluoride (KFHF) It is preferable that it is 1 type, or 2 or more types chosen from.

D) azole compound included in the etchant composition of the present invention controls the etching rate of the copper-based metal and serves to increase the process margin by reducing the CD loss of the pattern. The content of the D) azole compound is 0.1 to 5% by weight based on the total weight of the composition. When the D) azole compound is less than 0.1% by weight, the etching rate may be high, and thus the cisidose may be generated too large. When the D) azole compound is more than 5% by weight, since the etching rate of copper is lowered and the etching rate of molybdenum or molybdenum alloy is faster, the molybdenum or molybdenum alloy may be over-etched to cause undercut.

The D) azole compound is one or two selected from the group consisting of aminotetrazole, benzotriazole, tolyriazole, pyrazole and pyrrole It is preferable that it is above.

E) imidazole compounds included in the etchant composition of the present invention chelates the copper surface when etching copper, and uniformly etches the entire surface of the copper substrate, and simultaneously controls the copper etching rate. The content of the E) imidazole compound is 0.1 to 5% by weight. If the content of the E) imidazole compounds is less than 0.1% by weight, there is a problem in that copper etching uniformity is lowered, and a non-uniformity of CDiroth is generated, and the copper etching rate is too fast. When the content of the E) imidazole compound exceeds 5.0% by weight, the etching rate of copper is lowered and the etching rate of molybdenum or molybdenum alloy is increased, so that the taper angle of the copper molybdenum film or copper molybdenum alloy film is increased.

The E) imidazole compounds are imidazole, 2-methylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-aminoimidazole, 4-methylimidazole, 4-ethylimidazole. It is preferable that it is 1 type, or 2 or more types chosen from the group which consists of a sol and 4-propylimidazole.

The remaining amount of F) water contained in the etchant composition of the present invention is included, and the kind thereof is not particularly limited, but deionized water is preferable. More preferably, deionized water having a specific resistance value of the water (that is, the degree to which ions are removed in the water) is 18 kW / cm or more is used.

The etchant composition of the present invention is characterized in that it does not contain a separate carboxylic acid and phosphate.

The etchant composition of the present invention may further include a surfactant. The surfactant serves to decrease the surface tension to increase the uniformity of the etching. The surfactant is not particularly limited as long as it can withstand the etching liquid composition of the present invention and is compatible, but is not limited to anionic surfactants, cationic surfactants, zwitterionic surfactants, nonionic surfactants, and polyhydric alcohol type surfactants. It is preferably one or two or more selected from the group consisting of.

In addition to the above-mentioned components, a conventional additive may be further added, and as the additive, a metal ion blocking agent, a corrosion inhibitor, or the like may be used.

A) hydrogen peroxide (H ₂ O ₂ ), B) sulfuric acid, C) fluorine-containing compounds, D) azole compounds and E) imidazole compounds used in the present invention can be prepared by a conventionally known method, a semiconductor process It is desirable to have a purity of the dragon.

The etching liquid composition of the copper-based metal film according to the present invention may collectively etch the gate electrode, the gate wiring, the source / drain electrode and the data wiring of the liquid crystal display device made of the copper-based metal.

In addition, the present invention,

I) forming a copper-based metal film on the substrate;

II) selectively leaving a photoreactive material on the copper-based metal film; And

III) an etching method of a copper-based metal film comprising etching the copper-based metal film using the etchant composition of the present invention.

In the etching method of the present invention, the photoreactive material is preferably a conventional photoresist material, and may be selectively left by conventional exposure and development processes.

In addition, 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) a method of manufacturing an array substrate for a liquid crystal display device comprising forming a pixel electrode connected to the drain electrode;

The step a) includes forming a copper metal layer on a substrate and etching the copper metal layer with the etchant composition of the present invention to form a gate wiring;

The step d) includes forming a copper-based metal film and etching the copper-based metal film with the etchant composition of the present invention to form source and drain electrodes. will be.

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

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the scope of the present invention is not limited by the following examples.

Examples 1 to 6: Preparation of etching liquid composition of the copper-based metal film

To the etchant composition of Examples 1 to 6 according to the composition shown in Table 1.

H ₂ O ₂ Sulfuric acid Ammonium Fluoride Aminotetrazole Imidazole Deionized water Example 1 5 2 0.05 0.5 2 Balance Example 2 15 3 0.1 0.6 3 Balance Example 3 18 One 0.2 0.4 4 Balance Example 4 20 4 0.5 1.0 2 Balance Example 5 22 0.5 0.2 0.5 One Balance Example 6 25 4 0.1 1.0 5 Balance

Test Example: Evaluation of Characteristics of Etch Liquid Composition

An etching process of the copper-based metal film (Cu single layer and Cu / Mo-Ti double layer) was performed using the etching solution compositions of Examples 1 to 6. During the etching process, the temperature of the etchant composition was about 30 ° C., but the proper temperature may be changed as needed by other process conditions and other factors. The etching time may vary depending on the etching temperature, but usually proceeds about 30 to 180 seconds. The profile of the copper-based metal film etched in the etching process was examined using a cross-sectional SEM (Model S-4700, manufactured by Hitachi), and the results are shown in Table 2.

Etching Speed (Å / sec) Cu monolayer Cu / Mo-Ti Double Layer Cu Mo Example 1 40 to 60 40 to 60 6 to 8 Example 2 60 to 90 60 to 90 5 to 8 Example 3 20 to 40 20 to 40 4 to 6 Example 4 40 to 60 40 to 60 6 to 8 Example 5 50 to 80 50 to 80 6 to 8 Example 6 70 to 90 70 to 90 6 to 8

Referring to Table 2, the etching rate of Examples 1 to 6 was found to be appropriate. In addition, as can be seen in Figures 1 and 2, the copper-based metal film etched with the etchant composition according to Example 1 showed a good etching profile. 3, when the copper film-based metal film was etched with the etching solution composition according to Example 1, no etching residues remained.

Therefore, the etchant composition of the present invention provides excellent tapered profile of the copper-based metal film, the linearity of the pattern, and an appropriate etching rate, in particular, it can be seen that it has a characteristic that no residue remains after etching.

1 is a scanning electron micrograph of the etching cross-section after etching the Cu / Mo-Ti double layer using the etchant composition according to Example 1 of the present invention,

FIG. 2 is a scanning electron micrograph of etching Cu / Mo-Ti double layer using an etchant composition according to Example 1 of the present invention and then observing an overall etching profile;

3 is an electron scanning microscope photograph of a copper wiring peripheral surface after etching the Cu / Mo-Ti double layer using the etchant composition according to Example 1 of the present invention to confirm that no etching residues remain.

Claims (10)

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 device comprising forming a pixel electrode connected to the drain electrode; The step a) includes forming a copper-based metal film on the substrate and etching the copper-based metal film with an etchant composition to form a gate wiring; Step d) includes forming a copper-based metal film and etching the copper-based metal film with an etchant composition to form source and drain electrodes. The etching liquid composition, A) 5 to 25% by weight of hydrogen peroxide (H ₂ O ₂ ), B) 0.1 to 5% by weight of sulfuric acid, C) 0.01 to 1.0% by weight of fluorine-containing compound, D) azole compound 0.1 to 5% by weight, E) imidazole compounds 0.1 to 5.0% by weight, and F) water residual amount manufacturing method of an array substrate for a liquid crystal display device. The method according to claim 1, The method of manufacturing an array substrate for a liquid crystal display device, wherein the array substrate for a liquid crystal display device is a thin film transistor (TFT) array substrate. Regarding the total weight of the composition, A) 5 to 25 weight percent hydrogen peroxide (H ₂ O ₂ ); B) 0.1-5% by weight sulfuric acid; C) 0.01 to 1.0 wt% of a fluorine-containing compound; D) 0.1 to 5% by weight of an azole compound; E) 0.1 to 5.0% by weight of imidazole compounds; And F) An etchant composition of a copper-based metal film comprising a residual amount of water. The method according to claim 3, The C) fluorine-containing compound is an etching liquid composition of the copper-based metal film, characterized in that one or two or more selected from the group consisting of NH ₄ FHF, KFHF, NaFHF, NH ₄ F, KF, and NaF. The method according to claim 3, The D) azole compound is copper, characterized in that selected from the group consisting of aminotetrazole, benzotriazole, tolyriazole, pyrazole and pyrrole Etch solution composition of the metal film. The method according to claim 3, The E) imidazole compounds are imidazole, 2-methylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-aminoimidazole, 4-methylimidazole, 4-ethylimidazole. An etching liquid composition of a copper-based metal film, characterized in that one or two or more selected from the group consisting of sol and 4-propylimidazole. The method according to claim 3, The etchant composition of the copper-based metal film does not contain carboxylic acid and phosphate. The method according to claim 3, The copper-based metal film may include a single film of copper or a copper alloy, a copper molybdenum film including a molybdenum layer and a copper layer formed on the molybdenum layer, or a copper molybdenum including a molybdenum alloy layer and a copper layer formed on the molybdenum alloy layer. Etching liquid composition of the copper-based metal film, characterized in that the alloy film. I) forming a copper-based metal film on the substrate; II) selectively leaving a photoreactive material on the copper-based metal film; And Iii) etching the copper-based metal film using the etching solution composition according to claim 3; An array substrate for a liquid crystal display device comprising at least one of a gate wiring and a source and drain electrode etched using the etchant composition according to claim 3.

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