KR101845084B1 - Manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

The present invention provides a method of manufacturing a semiconductor device, comprising: a) forming a gate wiring on a substrate; b) forming a gate insulating layer on the substrate including the gate wiring; c) forming a semiconductor layer on the gate insulating layer; d) forming source and drain electrodes on the semiconductor layer; And forming a pixel electrode connected to the drain electrode, wherein the step a) includes the steps of: forming a copper-based metal film on the substrate and forming the copper-based metal film on the etchant composition Wherein the step d) includes forming a copper-based metal film on the semiconductor layer and etching the copper-based metal film with the etchant composition to form source and drain electrodes, Wherein the etchant composition comprises at least one compound selected from A) hydrogen peroxide (H ₂ O ₂ ), B) fluorine compounds, C) azole compounds, D) phosphonic acid derivatives and salts thereof, E) A copper (II) salt compound, and F) a residual amount of water. The present invention also relates to a method for producing an array substrate for a liquid crystal display device.

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 relates to a method of manufacturing an array substrate for a liquid crystal display device, an etching solution composition of a copper-based metal film, an etching method of a copper-based metal film using the etching solution composition, and an array substrate for a liquid crystal labeling device manufactured using the etching solution composition .

The process of forming a metal wiring on a substrate during the manufacture of a liquid crystal display device is usually performed by a metal film forming process such as sputtering, a photoresist coating process, a photoresist forming process in an optional region by exposure and development, And includes a cleaning process before and after the individual unit process, and the like. 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 composition is used.

In a liquid crystal display device manufactured as described above, resistance of metal wiring has recently become a major concern. This is because, to solve the RC signal delay problem in the TFT-LCD (thin film transistor-liquid crystal display), it is important to increase the panel size and realize the high resolution because the resistance is a main factor causing the RC signal delay. In order to realize reduction of the RC signal delay which is indispensably required for enlarging the TFT-LCD, it is essential to develop a low resistance material.

Chromium which was mainly used conventionally (Cr, specific resistance: 12.7 × 10 ^-8 Ωm), molybdenum (Mo, specific resistance: 5 × 10 ^-8 Ωm), aluminum (Al, specific resistance: 2.65 × 10 ^-8 Ωm), and alloys thereof Is difficult to be used for gate and data wiring used in a large-sized TFT LCD. Therefore, a copper-based metal film such as a copper film and a copper molybdenum film and an etchant composition therefor are attracting attention as a low resistance metal film.

However, since copper etching compositions known to date do not satisfy the performance required by the user, research and development for improving the performance is required. Particularly, the conventional copper-based etchant compositions have a taper of 60 to 70 degrees at the time of etching, so that the step coverage is poor in a specific device and the reliability of the device is lowered. Further, the length of the Mo-Ti tail is not less than 0.1 占 퐉, which causes a problem of a decrease in transmittance and a problem of uneven image quality.

The present invention is characterized in that a profile having excellent etching uniformity and linearity is formed and shows a low taper of 40 to 50 degrees in order to improve step coverage from a specific device to a subsequent process while a Mo- And to provide an etching solution composition of a copper-based metal film which can reduce the possibility of occurrence of a stain problem on the image quality and improve the transmittance and which do not leave a residue of the metal film.

Another object of the present invention is to provide a copper-based metal film etchant composition capable of collectively etching gate electrodes, gate wirings, source / drain electrodes, and data wirings.

It is still another object of the present invention to provide a method of etching a copper-based metal film using the etchant composition and a method of manufacturing an array substrate for a liquid crystal display device.

In order to achieve the above object, the present invention relates to a composition comprising: A) 5 to 25% by weight of hydrogen peroxide (H ₂ O ₂ ); B) 0.01 to 1.0% by weight of a fluorine compound; C) 0.1 to 5% by weight of an azole-based compound; D) 0.1 to 10.0% by weight of at least one compound selected from phosphonic acid derivatives and salts thereof; E) 0.1 to 1.0% by weight of a copper (II) salt compound; And F) the remaining amount of water.

The present invention also provides a method of manufacturing a semiconductor device, comprising: (I) forming a copper-based metal film on a 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 of the present invention.

The present invention also provides a method of manufacturing a semiconductor device, comprising the steps of: a) forming a gate wiring on a 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:

The step a) includes forming a copper-based metal film on the substrate and etching the copper-based metal film with the etchant composition of the present invention to form a gate wiring, wherein the step d) includes forming a copper- And etching the copper-based metal film with the etchant composition of the present invention to form a source and a drain electrode. The present invention also provides a method of manufacturing an array substrate for a liquid crystal display device.

The present invention also provides an array substrate for a liquid crystal display comprising at least one of gate wirings and source / drain electrodes etched using the etchant composition of the present invention.

The etching composition of the present invention is excellent in etching uniformity and linearity and low in taper profile when etching a copper-based metal film, and can prevent the occurrence of stain problems and does not generate residues, It is free from problems such as poor wiring and reduction in luminance.

In addition, the etchant composition of the present invention can collectively etch gate electrodes, gate wirings, source / drain and data wirings at the time of manufacturing an array substrate for a liquid crystal display, thereby simplifying the etching process and maximizing the process yield.

Therefore, the etchant composition of the present invention can be very usefully used in manufacturing an array substrate for a liquid crystal display device in which a circuit of a large screen and a high luminance is realized.

FIG. 1 is a scanning electron microscope (SEM) image of a Cu / Mo-Ti bilayer film etched using an etchant composition of Comparative Example 2 of the present invention,
FIG. 2 is a scanning electron microscope (SEM) image of a Cu / Mo-Ti bilayer film etched using the etchant composition of Example 1 of the present invention, and then the etched cross section was observed.

Hereinafter, the present invention will be described in detail.

A) hydrogen peroxide (H ₂ O ₂ ) in an amount of from 5 to 25% by weight; B) 0.01 to 1.0% by weight of a fluorine compound; C) 0.1 to 5% by weight of an azole-based compound; D) 0.1 to 10.0% by weight of at least one compound selected from phosphonic acid derivatives and salts thereof; E) 0.1 to 1.0% by weight of a copper (II) salt compound; And F) the remaining amount of water.

In the present invention, the copper-based metal film includes copper as a constituent component of the film, and includes a multilayer film such as a single film and a double film. For example, a single film of copper or a copper alloy, a copper molybdenum film, a copper molybdenum alloy film, or the like as a multilayer film.

The copper molybdenum film includes 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 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 Molybdenum alloy.

A) hydrogen peroxide (H ₂ O ₂ ) contained in the etchant composition of the present invention is a main component for etching the copper-based metal film, and its content is 5 to 25% by weight based on the total weight of the composition. If the A) content of hydrogen peroxide is less than 5% by weight, the etching of the copper-based metal becomes impossible or the etching rate becomes very slow. When the content of hydrogen peroxide is more than 25% by weight, the etching rate is entirely accelerated.

The fluorine-containing compound (B) contained in the etchant composition of the present invention means a compound capable of releasing fluorine ions by being dissolved in water. The B) fluorine compound serves to remove residues which are inevitably generated in a solution which simultaneously etches the copper film and the molybdenum film. The content of the fluorine-containing compound (B) is 0.01 to 1.0% by weight based on the total weight of the composition. If the content of the fluorine compound (B) is less than 0.01% by weight, etch residue may be generated. If the content of the fluorine compound exceeds 1.0% by weight, the etching rate of the glass substrate may increase.

The B) fluorine compound is not particularly limited as long as it can be dissociated into fluorine ions or polyatomic fluorine ions in a solution used in the field, but ammonium fluoride (NH ₄ F), sodium fluoride selected from the group consisting of fluoride: NaF, potassium fluoride (KF), ammonium bifluoride (NH ₄ FHF), sodium bifluoride (NaFHF) and potassium bifluoride (KFHF) Or more.

The C) azole-based compound contained in the etchant composition of the present invention controls the etch rate of the copper-based metal and reduces the CD loss of the pattern, thereby enhancing the process margin.

The content of the C) azole-based compound is 0.1 to 5% by weight based on the total weight of the composition. If the content of the C) azole compound is less than 0.1% by weight, the etching rate may become too high and the seed loss may be excessively large. If the content exceeds 5% by weight, the etching rate of the copper may be slowed down and the etching of the molybdenum or molybdenum alloy Molybdenum or molybdenum alloys can overfuse and undercuts can occur because of the faster speed.

Examples of the C) azole-based compound include aminotetrazole, benzotriazole, tolytriazole, pyrazole, pyrrole, imidazole, 2-methyl 2-ethylimidazole, 2-ethylimidazole, 2-ethylimidazole, 2-ethylimidazole, 2-ethylimidazole, 2-ethylimidazole, They may be used alone or in combination of two or more.

The at least one compound selected from D) phosphonic acid derivatives and salts thereof contained in the etchant composition of the present invention is a compound which chelates copper ions dissolved in an etchant when the copper film is etched to inhibit the activity of copper ions thereby decomposing hydrogen peroxide Inhibit the reaction. When the activity of the copper ion is lowered, the process can be performed stably while using the etching solution.

The content of at least one compound selected from the D) phosphonic acid derivatives and salts thereof is 0.1 to 10.0% by weight based on the total weight of the composition. If the amount of the at least one compound selected from the D) phosphonic acid derivative and its salt is less than 0.1% by weight, the etching uniformity is lowered and the decomposition of hydrogen peroxide accelerates. When the content exceeds 10.0% by weight, A problem occurs that the speed becomes too fast.

Representative examples of the phosphonic acid derivatives in the at least one compound selected from the above phosphonic acid derivatives and salts thereof include 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) diphosphonic acid). Typical examples of the phosphonic acid derivative salt include sodium or potassium salts of 1-hydroxyethylidene-1,1-diphosphonic acid.

The E) copper (II) salt compound contained in the etchant composition of the present invention serves to lower the taper at the time of etching. By lowering the taper of the copper film in a particular device, step coverage can be improved, which can help drive the device. In addition, the transmittance can be improved by shortening the length of the Mo-Ti tail.

The content of the E) copper (II) salt compound is 0.1 to 1.0% by weight based on the total weight of the composition. If the content of the E) copper (II) salt compound is less than 0.1% by weight, the ability to lower the taper is deteriorated. If the amount is more than 1.0% by weight, the stability of the chemical solution is deteriorated and an undercut phenomenon of the Mo-Ti film appears.

Examples of the E) copper (II) salt compound include copper acetate, copper chloride, copper nitrate, and copper sulfate. Or two or more of them may be used together.

F) The remaining amount of water contained in the etchant composition of the present invention is not particularly limited, but deionized water is preferred. More preferably, it is preferable to use deionized water having a specific resistance value of water (that is, the degree of removal of ions in water) of 18 MΩ / cm or more.

The etchant composition of the present invention may further comprise a surfactant. The surfactant serves to lower the surface tension and increase the uniformity of the etching. The surfactant is not particularly limited as long as it can withstand the etching composition of the present invention and is compatible with the surfactant. However, the surfactant may be an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant and a polyhydric alcohol surfactant , Or a combination thereof.

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.

At least one compound selected from A) hydrogen peroxide (H ₂ O ₂ ), B) fluorine compounds, C) azole compounds, D) phosphonic acid derivatives and salts thereof, E) copper Compound and F) the remaining amount of water can be prepared by a conventionally known method and preferably has a purity for semiconductor processing.

The etchant composition of the present invention can collectively etch gate electrodes, gate wirings, source / drain electrodes, and data wirings of a liquid crystal display device made of a copper-based metal.

Further, according to the present invention,

I) forming a copper-based metal film on a 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 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.

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:

The step a) includes forming a copper-based metal film on the substrate and etching the copper-based metal film with the etchant composition of the present invention to form a gate wiring,

And d) forming a copper-based metal film on the semiconductor layer and etching the copper-based metal film with the etchant composition of the present invention to form source and drain electrodes. And a manufacturing method thereof.

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

Experimental Example : Copper series Metal film Etchant  Preparation of composition

The etchant compositions of Examples 1 to 4 and Comparative Examples 1 and 2 were prepared according to the compositions shown in Table 1 below.

H ₂ O ₂ Ammonium fluoride Aminotetrazole HEDP Cu (II) salt Deionized water Example 1 10 0.07 0.5 0.5 0.5 Balance Example 2 15 0.14 0.6 1.0 One Balance Example 3 5 0.4 1.0 5.0 0.5 Balance Example 4 25 0.8 4.0 9.0 1.0 Balance Comparative Example 1 10 0.07 0.5 0.5 - Balance Comparative Example 2 15 0.14 0.6 1.0 - Balance

* HEDP: 1-hydroxyethylidene-1,1-diphosphonic acid

Test Example : Etchant  Evaluation of composition characteristics

Etching of copper-based metal films (Cu single film and Cu / Mo-Ti double film) was performed using the etchant compositions of Examples 1 to 4 and Comparative Examples 1 and 2. The temperature of the etchant composition during the etching process is about 30 캜, but the proper temperature may be changed as needed depending on other process conditions and other factors. The etching time may vary depending on the etching temperature, but is usually 30 to 180 seconds. The profile of the copper-based metal film etched in the etching process was inspected using a cross-sectional SEM (product of Hitachi, model name S-4700), and the results are shown in Table 2 below.

Etching speed (Å / sec) Taper angle (˚) Tail length (탆) Cu single membrane Cu / Mo-Ti bilayer Cu single membrane Cu / Mo-Ti Mo-Ti Cu Mo-Ti Double membrane Example 1 55 ~ 75 55 ~ 75 9-11 45 42 0.08 탆 Example 2 75 ~ 105 75 ~ 105 10-12 46 43 0.05 탆 Example 3 45 ~ 65 45 to 60 7 ~ 9 44 43 0.09 탆 Example 4 70 ~ 95 70 to 90 9-11 42 45 0.06 탆 Comparative Example 1 55 ~ 65 55 ~ 65 7 ~ 9 68 64 0.15 탆 Comparative Example 2 65 ~ 85 65 ~ 85 8-10 65 63 0.13 탆

From the results in Table 2, it was confirmed that the etching rates of Examples 1 to 4 and Comparative Examples 1 and 2 were appropriate. 1 and 2, the copper-based metal film etched with the etchant composition according to Comparative Example 2 had a taper of about 63 to 65 degrees and a Mo-Ti tail length of 0.13 mu m. In Example 1 It can be confirmed that the taper is etched to about 42 to 45 degrees and the Mo-Ti tail length to 0.08 mu m when the copper-based metal film is etched with the etchant composition.

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) forming a pixel electrode connected to the drain electrode, the method comprising the steps of:
The step a) includes forming a copper / molybdenum-titanium double layer on the substrate and etching the copper / molybdenum-titanium double layer with the etchant composition to form a gate wiring,
The step d) includes forming a copper / molybdenum-titanium double layer on the semiconductor layer and etching the copper / molybdenum-titanium double layer with the etchant composition to form source and drain electrodes,
The etchant composition of the copper / molybdenum-titanium double layer film comprises: A) from 5 to 25% by weight of hydrogen peroxide (H ₂ O ₂ ), based on the total weight of the composition; B) 0.01 to 1.0% by weight of a fluorine compound; C) 0.1 to 5% by weight of an azole-based compound; D) 0.1 to 10.0% by weight of at least one compound selected from phosphonic acid derivatives and salts thereof; E) 0.1 to 1.0% by weight of a copper (II) salt compound; And F) residual water,
The at least one compound selected from the above phosphonic acid derivatives and salts thereof is a copper ion chelating agent and may be 1-hydroxyethylidene-1,1-diphosphonic acid, 1-hydroxyethylidene- Potassium salt of 1-hydroxyethylidene-1,1-diphosphonic acid, sodium salt of sodium hydroxide, potassium hydroxide,
Wherein the length of the Mo-Ti tail after etching is less than 0.1 占 퐉. The method of manufacturing an array substrate for a liquid crystal display according to claim 1, wherein the array substrate for a liquid crystal display is a thin film transistor (TFT) array substrate. With respect to the total weight of the composition,
A) 5 to 25% by weight hydrogen peroxide (H ₂ O ₂ );
B) 0.01 to 1.0% by weight of a fluorine compound;
C) 0.1 to 5% by weight of an azole-based compound;
D) 0.1 to 10.0% by weight of at least one compound selected from phosphonic acid derivatives and salts thereof;
E) 0.1 to 1.0% by weight of a copper (II) salt compound; And
F) residual water,
The at least one compound selected from the above phosphonic acid derivatives and salts thereof is a copper ion chelating agent and may be 1-hydroxyethylidene-1,1-diphosphonic acid, 1-hydroxyethylidene- Potassium salt of 1-hydroxyethylidene-1,1-diphosphonic acid, sodium salt of sodium hydroxide, potassium hydroxide,
The etchant composition of a copper / molybdenum-titanium double film, wherein the length of the Mo-Ti tail after etching is less than 0.1 占 퐉. _{4. The} etchant composition for a copper / molybdenum-titanium double layer according to claim 3, wherein the fluorine compound (B) is at least one selected from the group consisting of NH ₄ FHF, KFHF, NaFHF, NH ₄ F, KF and NaF. 4. The method of claim 3, wherein the C) azole compound is selected from the group consisting of aminotetrazole, benzotriazole, tolytriazole, pyrazole, pyrrole, imidazole, 2- Is selected from the group consisting of methylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-aminoimidazole, 4-methylimidazole, 4-ethylimidazole and 4-propylimidazole At least one copper / molybdenum-titanium double-layer film. delete The method of claim 3, wherein the E) copper (II) salt compound is at least one selected from the group consisting of copper acetate, copper chloride, copper nitrate, and copper sulfate Wherein the copper / molybdenum-titanium double-film etchant composition is a copper / molybdenum-titanium double-film etchant composition. delete I) forming a copper / molybdenum-titanium double film on the substrate;
II) selectively leaving a photoreactive material on the copper / molybdenum-titanium double layer; And
III) etching the copper / molybdenum-titanium double film using the etchant composition of claim 3; delete

Images