KR20080004894A - Low viscosity etchant for metal electrode - Google Patents

Abstract

A low viscosity etchant for metal electrodes is provided to control an etching speed in a wide range when a metal layer is etched, to maintain etching uniformity, lower a taper angle, and to maximize an etching effect even in an oblique apparatus. An etchant for metal layers includes 5-40wt%, based on the total weight of the composition, of sulfuric acid, 0.5-30wt%, based on the total weight of the composition, of nitric acid, 0.1-10wt%, based on the total weight of the composition, of a halogen-based additive, 0.5-20wt%, based on the total weight of the composition, of an organic acid or salt derived from organic acid, and the balance of water.

Description

LOW VISCOSITY ETCHANT FOR METAL ELECTRODE}

1A to 1F are views illustrating a manufacturing process of an array substrate for a liquid crystal display using a metal film etching solution according to the present invention;

2 is a scanning electron micrograph of the surface after etching the molybdenum single layer with a metal film etching solution according to the present invention,

3 is a scanning electron micrograph of the surface after etching the molybdenum / aluminum alloy double layer with a metal film etching solution according to the present invention,

4 is a scanning electron micrograph of the surface after etching the indium oxide film with a metal film etching solution according to the present invention.

* Description of the symbols for the main parts of the drawings

10: substrate 20: metal layer

20a: gate electrode 30: gate insulating layer

40: active layer 41: omic contact layer

50 source electrode 51 drain electrode

60: insulating film 70: pixel electrode

The present invention relates to a metal film etching solution, and more particularly, to a metal film capable of etching a single film or a multilayer film formed of at least one selected from the group consisting of indium oxide film, aluminum, aluminum alloy, molybdenum and molybdenum alloy. It relates to an etching solution.

In general, the liquid crystal display includes a liquid crystal panel including a thin film transistor substrate, a color filter substrate, and a liquid crystal layer injected between the two substrates.

The liquid crystal layer is printed around the edges of the two substrates and bonded with a sealant to trap the liquid crystal layer. Since the liquid crystal panel is a non-light emitting device, a backlight unit is positioned on the rear surface of the thin film transistor substrate. The amount of light emitted from the backlight is controlled according to the arrangement of liquid crystal molecules.

Wiring is formed on the thin film transistor substrate to transmit a signal to the liquid crystal layer. The wiring of the thin film transistor substrate includes a gate wiring and a data wiring.

The gate line includes a gate line to which a gate signal is applied and a gate electrode of the thin film transistor. The data line is insulated from the gate line and the drain electrode and the source electrode forming the data electrode of the thin film transistor and the data line to apply the data signal. Include. Here, the signal coming through the drain electrode is directly transmitted to the liquid crystal side by the pixel electrode made of a transparent metal.

Such wiring may be made of a metal single layer or an alloy single layer, or may be formed in multiple layers to compensate for the disadvantages of each metal or alloy and to obtain desired physical properties.

Aluminum is commonly used to form wires. Pure aluminum has low corrosion resistance to chemicals and may cause wiring defects in subsequent processes. Multiple layers in which metal layers such as molybdenum, chromium, tungsten, and tin are laminated may also be used.

This multilayer deposited on the substrate material is patterned into the wiring via etching. Etching includes dry etching and wet etching, and uniform etching and high productivity wet etching are frequently used.

As an example of the etching solution used for such wet etching, a technique for etching a Mo / Al-Nd bilayer using an etching solution containing phosphoric acid, nitric acid, acetic acid and water is disclosed in Korean Patent No. 0330582 by the present applicant. As described above, a technique of etching Mo / Al bilayer using an etching solution including phosphoric acid, nitric acid, acetic acid, and an oxidizing agent and water has been presented in Korean Patent No. 0315648.

Here, by changing the composition ratio of phosphoric acid, nitric acid and acetic acid of the etching solution or introducing an additive (for example, an oxidizing agent) having a special effect, the cross-section of the upper molybdenum layer protruding to the outside of the lower aluminum alloy layer is removed. It is possible to prevent the occurrence of a poor profile to have, and to obtain a profile so good that no additional dry etching is required.

However, in the etching solution consisting of phosphoric acid, nitric acid and acetic acid as a main component, the range in which the composition can be changed is small, and thus there is a limitation in controlling the etching rate. In addition, as the size of the substrate gradually increases in size, the etching solution of phosphoric acid, nitric acid, and acetic acid having high viscosity does not cause smooth flow on a large substrate, and tends to be in excessive contact with a limited area, resulting in unevenness in overall uniformity. Can be.

On the other hand, in recent years, the large-size etching equipment is inclined to advance the substrate to prevent the discharge of the chemical liquid along with the substrate. However, when the etching solution with high viscosity is used, the movement of the chemical liquid is limited despite the inclination. Difficult to do Accordingly, the present applicant has developed a metal film etching solution having new properties to solve this problem.

Accordingly, an object of the present invention is to control the etching rate in a wide range when etching the metal film, to maintain the etching uniformity even when the size of the substrate in the manufacturing of the array substrate for the liquid crystal display device, while reducing the taper angle, It is to provide a metal film etching solution that can maximize the effect even on inclined equipment.

The object is, in accordance with the invention, 5 to 40% by weight sulfuric acid relative to the total weight of the composition; 0.5-30 weight percent nitric acid relative to the total weight of the composition; 0.1-10% by weight of halogen-based additives relative to the total weight of the composition; 0.5-20% by weight of the organic acid or salt derived from the organic acid relative to the total weight of the composition and the remaining components are achieved by a metal film etching solution, characterized in that it comprises water.

Here, the halogen-based additive is HF, (NH ₄ ) F, (NH ₄ ) HF ₂ , KF, NaF, MgF ₂ , AlF ₃ , HCl, (NH ₄ ) Cl, KCl, NaCl, MgCl ₂ , FeCl ₃ , AlCl ₃ , HBr, (NH ₄ ) Br, KBr, NaBr, MgBr ₂ , AlBr ₃ , HI, (NH ₄ ) I, KI, NaI, MgI ₂ And it is preferably selected from the group consisting of AlI ₃ .

The organic acid has a carbon number of 5 or less and contains a carboxyl group, and the salt derived from the organic acid is in the group consisting of salts in which one or more hydrogens are substituted with ammonium ion, alkali metal ion or alkaline earth metal ion. It is preferred to be selected.

In addition, one or more of an etching control agent, a surfactant, a metal ion sequestrant, a corrosion inhibitor and a pH adjusting agent may be further included.

The metal film etching solution of the present invention is preferably used for etching a single film or a multilayer film provided with at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum, molybdenum alloy and indium oxide film.

In addition, it is preferable to use for etching the gate electrode, the source electrode, the drain electrode and the pixel electrode of the TFT-LCD.

On the other hand, according to the present invention, (a) forming a metal layer on a substrate; (b) etching the metal layer to form a gate electrode; (c) forming a gate insulating layer on the gate electrode; (d) forming a semiconductor layer on the gate insulating layer; (e) forming source and drain electrodes on the semiconductor layer; (f) forming a pixel electrode on the source and drain electrodes, and in at least one of the steps (b), (e), and (f), etching with the metal film etching solution is performed. It is also achieved by a method for producing an array substrate for liquid crystal display devices.

In the step (b), the metal layer is preferably a single film or a multilayer film provided with at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum and molybdenum alloy.

In the step (e), the source and the drain electrode may be formed by etching a single layer or a multilayer layer formed of at least one selected from aluminum, an aluminum alloy, molybdenum, and molybdenum alloy with the metal film etching solution.

In the step (f), the pixel electrode may be formed by etching an indium oxide film with the metal film etching solution.

Hereinafter, the present invention will be described in detail.

The metal film etching solution according to the present invention is a group consisting of an indium oxide film used for a pixel electrode of a TFT-LCD, a gate electrode, a source electrode and a drain electrode of a TFT-LCD, an aluminum alloy, molybdenum and molybdenum alloy. It is a solution for etching a single film or a multilayer film is provided with one or more selected from.

Here, a single film or a multilayer film formed of at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum and molybdenum alloy may be varied in form, and may include a single film such as Al, Mo, Al-Nd, and Mo-W; Double membranes such as Mo / Al-Nd and Mo-W / Al; Triple films, such as Mo / Al / Mo, Mo / Al-Nd / Mo, and Mo-W / Al / Mo-W, etc. are mentioned.

The aluminum alloy and molybdenum alloy may be formed of an alloy containing aluminum or molybdenum as a main component and containing other metals such as Nd, W, Ti, Cr, Ta, Hf, Zr, Nb, and V; Nitride, silicide and carbide forms of molybdenum or aluminum; The aluminum alloy or molybdenum alloy may be in the form of nitrides, silicides, carbides and the like.

In addition, examples of the indium oxide film used to form the pixel electrode include an indium zinc oxide (hereinafter referred to as "IZO") film, an indium tin oxide (hereinafter referred to as "ITO") film, and the like. Can be.

Here, IZO is an oxide in which In ₂ O ₃ and ZnO are mixed in an appropriate ratio, and ITO is an oxide in which In ₂ O ₃ and SnO ₂ are mixed in an appropriate ratio, and in the case of ITO, crystalline and It is classified as amorphous.

Metal film etching solution according to the present invention for etching such a metal film is 5 to 40% by weight of sulfuric acid based on the total weight of the composition; 0.5-30 weight percent nitric acid relative to the total weight of the composition; 0.1-10% by weight of halogen-based additives relative to the total weight of the composition; 0.5-20% by weight of organic acid or salt derived from the organic acid, relative to the total weight of the composition; The remaining components are achieved by the metal film etching solution, which comprises water. If necessary, a small amount of an etching regulator, a surfactant, a metal ion sequestrant, a corrosion inhibitor, a pH regulator, and the like may be added.

Sulfuric acid is a main oxidizing agent, if less than 5% by weight may not be enough etching due to the lack of etching power, when more than 40% by weight of the etching power due to excessive etching and the remaining metal film area of the role as an electrode You may not be able to perform it.

Nitric acid acts as an auxiliary oxidant, controlling the etching rate and lowering the taper angle. In order to control the etching rate, the composition ratio may be variously applied from 0.5 wt% to 30 wt%, and the taper angle may be adjusted according to the composition ratio. If the nitric acid is not included or less than 0.5% by weight, it is not etched or etched at a very slow etching rate, the taper angle is also very large. In addition, if it exceeds 30% by weight, it is difficult to control the process due to the excessive etching rate and the area of the remaining metal film is also small, making it difficult to perform a role as an electrode.

Halogen-based additives are etching initiators and etching aids, which activate the surface of the metal film to be etched by the main oxidizing agent, and compensate for insufficient etching power during the etching process to prevent residues and poor profiles. It also plays a role. When the halogen-based additive is less than 0.1% by weight, residue of the metal film may occur due to insufficient etching force, and the linearity of the profile may be insufficient. If more than 10% by weight, due to excessive etching force, the wiring shape after etching is poor, and in some processes may attack the glass substrate may cause a process failure.

Here, the halogen-based additive is of an inorganic halide, halogen elements F ^-, Cl ^-, Br ^- is preferably a compound containing a ^-, I.

For example, HF, (NH ₄ ) F, (NH ₄ ) HF ₂ , KF, NaF, MgF ₂ , AlF ₃ , HCl, (NH ₄ ) Cl, KCl, NaCl, MgCl ₂ , FeCl ₃ , AlCl ₃ , HBr , (NH ₄ ) Br, KBr, NaBr, MgBr ₂ , AlBr ₃ , HI, (NH ₄ ) I, KI, NaI, MgI ₂ , AlI ₃ , and the like. However, it is not limited thereto.

Organic acids or salts derived from organic acids stabilize the carboxyl groups contained therein to chelate metal ions so that the main oxidant oxidizes the metal film and becomes ions in the process of etching so that they can be dissolved in the etching solution. At the same time, the etched metal ions are also reduced to the substrate to prevent resorption. In addition, organic acids or salts derived from organic acids are compounds having a lower viscosity than water, and exhibit lower viscosity characteristics than conventional etching liquids, so that the movement on the substrate can be accelerated, thereby preventing the etching liquid from being released with the substrate in the inclined etching equipment. Giving can be maximized.

When the content of the organic acid or the salt derived from the organic acid is less than 0.5% by weight, the etched metal ions may not be sufficiently chelated, and may be reduced to ions in the metal to be resorbed to the substrate. The components that are rapidly adsorbed to the membrane to provide the etching force act on the metal film and interfere with the oxidation process, so that the etching process does not occur smoothly, and as the viscosity of the etchant becomes too low, The movement is excessive and does not provide enough time for stable etching.

The organic acid or salt derived from the organic acid here is preferably selected from the group consisting of organic acids or salts derived from such organic acids. More preferably, the organic acid has a carbon number of 5 or less and includes a carboxyl group, and the salt derived from the organic acid includes one to two or more hydrogens substituted with ammonium ion, alkali metal ion or alkaline earth metal ion. It is selected from the group consisting of salts. However, it is not limited thereto.

Although water is not specifically limited, 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.

Hereinafter, examples and comparative examples according to the present invention will be described in detail. However, the present invention is not limited to the following examples.

Etching characteristics  exam

A molybdenum (Mo) single film, a Mo / Al-Nd double film, and an amorphous ITO single film substrate were prepared. An etching solution containing sulfuric acid, nitric acid, KF, oxalic acid, and the residual amount of water as a composition ratio with respect to the total weight of the total compositions described in Tables 1, 2, and 3 was prepared to be 180 kg. In addition, an etching solution containing sulfuric acid, nitric acid, (NH ₄ ) F, potassium acetate, and the residual amount of water in a composition ratio with respect to the total weight of the total compositions shown in Tables 4, 5, and 6 was prepared to be 180 Kg. An etching solution prepared in a spray etching method (manufactured by KDNS, model name: ETCHER (TFT)) was added thereto, warmed by setting the temperature to 30 ° C, and the etching process was performed when the temperature reached 30 ± 0.5 ° C. O / E (Over Etch) was performed at 30% based on EPD (End Point Detection) of the pad part. After the substrate was inserted and spraying was started and the etching was completed, the substrate was taken out, washed with deionized water, dried using a hot air dryer, and removed using a photoresist stripper. After washing and drying, the etching profile was evaluated by using an electron scanning microscope (SEM; manufactured by HITACHI, model name: S-4700) with an inclination angle, loss of side etching CD (critical dimension), and etching residue. The results are shown in Tables 1-6.

Table 1 Molybdenum Monolayer

Composition (wt%) (sulfuric acid / nitric acid / KF / oxalic acid / water) Etch Speed (Å / sec) Etching characteristics Example 1 5/6 / 0.5 / 1 / 87.5 60 ○ Example 2 15/6 / 0.5 / 1 / 77.5 130 ◎ Example 3 25/6 / 0.5 / 1 / 67.5 250 ◎ Example 4 40/6 / 0.5 / 1 / 52.5 300 ◎ Example 5 15/15 / 0.5 / 1 / 68.5 220 ◎ Example 6 15/30 / 0.5 / 1 / 53.5 320 ○ Example 7 15/6 / 0.1 / 1 / 77.9 100 ○ Example 8 15/6/5/1/73 180 ◎ Example 9 15/6/10/1/68 200 ○ Example 10 15/6 / 0.5 / 5 / 73.5 120 ◎ Example 11 15/6 / 0.5 / 10 / 68.5 110 ○ Example 12 20/10 / 0.5 / 5 / 64.5 250 ○ Comparative Example 1 3/6 / 0.5 / 1 / 89.5 X Not etched Comparative Example 2 50/6 / 0.5 / 1 / 42.5 1000 X Comparative Example 3 25/0 / 0.5 / 1 / 73.5 X Not etched Comparative Example 4 15/35 / 0.5 / 1 / 48.5 1200 X Comparative Example 5 15/6/0/1/78 40 X Comparative Example 6 15/6/12/1/66 400 Board Etched Comparative Example 7 15/6 / 0.5 / 0 / 78.5 160 ○ Comparative Example 8 15/6 / 0.5 / 22 / 56.5 Not etched Precipitate occurrence ◎: Excellent 2) ○: Good 3) △: Normal 4) X: Poor

Table 2: Molybdenum / Aluminum Alloy Double Layer

Composition (wt%) (sulfuric acid / nitric acid / KF / oxalic acid / water) Etch Speed (Å / sec) Etching characteristics Example 1 5/6 / 0.5 / 1 / 87.5 30 ○ Example 2 15/6 / 0.5 / 1 / 77.5 60 ◎ Example 3 25/6 / 0.5 / 1 / 67.5 95 ◎ Example 4 40/6 / 0.5 / 1 / 52.5 160 ◎ Example 5 15/15 / 0.5 / 1 / 68.5 90 ◎ Example 6 15/30 / 0.5 / 1 / 53.5 180 △ Example 7 15/6 / 0.1 / 1 / 77.9 60 ◎ Example 8 15/6/5/1/73 50 ○ Example 9 15/6/10/1/68 50 △ Example 10 15/6 / 0.5 / 5 / 73.5 60 ◎ Example 11 15/6 / 0.5 / 10 / 68.5 60 ○ Example 12 20/10 / 0.5 / 5 / 64.5 55 ○ Comparative Example 1 3/6 / 0.5 / 1 / 89.5 X Not etched Comparative Example 2 50/6 / 0.5 / 1 / 42.5 250 X Comparative Example 3 25/0 / 0.5 / 1 / 73.5 X Not etched Comparative Example 4 15/35 / 0.5 / 1 / 48.5 320 X Comparative Example 5 15/6/0/1/78 30 Residue Comparative Example 6 15/6/12/1/66 60 Board Etched Comparative Example 7 15/6 / 0.5 / 0 / 78.5 65 Overhang Comparative Example 8 15/6 / 0.5 / 22 / 56.5 Not etched Precipitate occurrence ◎: Excellent 2) ○: Good 3) △: Normal 4) X: Poor

Table 3 Amorphous ITO Membrane

Composition (wt%) (sulfuric acid / nitric acid / KF / oxalic acid / water) Etch Speed (Å / sec) Etching characteristics Example 1 5/6 / 0.5 / 1 / 87.5 5 ○ Example 2 15/6 / 0.5 / 1 / 77.5 9.6 ◎ Example 3 25/6 / 0.5 / 1 / 67.5 10.2 ◎ Example 4 40/6 / 0.5 / 1 / 52.5 10.5 ◎ Example 5 15/15 / 0.5 / 1 / 68.5 9.9 ◎ Example 6 15/30 / 0.5 / 1 / 53.5 12.1 ◎ Example 7 15/6 / 0.1 / 1 / 77.9 6.4 ○ Example 8 15/6/5/1/73 14.1 ◎ Example 9 15/6/10/1/68 14.2 ◎ Example 10 15/6 / 0.5 / 5 / 73.5 8.4 ◎ Example 11 15/6 / 0.5 / 10 / 68.5 8.4 ○ Example 12 20/10 / 0.5 / 5 / 64.5 10.8 ◎ Comparative Example 1 3/6 / 0.5 / 1 / 89.5 4.4 ○ Comparative Example 2 50/6 / 0.5 / 1 / 42.5 15.0 △ Comparative Example 3 25/0 / 0.5 / 1 / 73.5 X Not etched Comparative Example 4 15/35 / 0.5 / 1 / 48.5 13.5 ○ Comparative Example 5 15/6/0/1/78 X Not etched Comparative Example 6 15/6/12/1/66 14.4 Board Etched Comparative Example 7 15/6 / 0.5 / 0 / 78.5 9.4 ○ Comparative Example 8 15/6 / 0.5 / 22 / 56.5 Not etched Precipitate occurrence ◎: Excellent 2) ○: Good 3) △: Normal 4) X: Poor

Table 4 Molybdenum Monolayer

Composition (wt%) (sulfuric acid / nitric acid / NH ₄ F / potassium acetate / water) Etch Speed (Å / sec) Etching characteristics Example 1 5/6 / 0.5 / 1 / 87.5 50 ○ Example 2 15/6 / 0.5 / 1 / 77.5 130 ◎ Example 3 25/6 / 0.5 / 1 / 67.5 230 ◎ Example 4 40/6 / 0.5 / 1 / 52.5 310 ◎ Example 5 15/15 / 0.5 / 1 / 68.5 200 ◎ Example 6 15/30 / 0.5 / 1 / 53.5 310 ○ Example 7 15/6 / 0.1 / 1 / 77.9 100 ○ Example 8 15/6/5/1/73 180 ◎ Example 9 15/6/10/1/68 180 ○ Example 10 15/6 / 0.5 / 5 / 73.5 100 ◎ Example 11 15/6 / 0.5 / 10 / 68.5 100 ○ Example 12 20/10 / 0.5 / 5 / 64.5 280 ○ Comparative Example 1 3/6 / 0.5 / 1 / 89.5 X Not etched Comparative Example 2 50/6 / 0.5 / 1 / 42.5 950 X Comparative Example 3 25/0 / 0.5 / 1 / 73.5 X Not etched Comparative Example 4 15/35 / 0.5 / 1 / 48.5 1200 X Comparative Example 5 15/6/0/1/78 40 X Comparative Example 6 15/6/12/1/66 380 Board Etched Comparative Example 7 15/6 / 0.5 / 0 / 78.5 180 ○ Comparative Example 8 15/6 / 0.5 / 22 / 56.5 20 X ◎: Excellent 2) ○: Good 3) △: Normal 4) X: Poor

Table 5 Molybdenum / Aluminum Alloy Double Layer

Composition (wt%) (sulfuric acid / nitric acid / NH ₄ F / potassium acetate / water) Etch Speed (Å / sec) Etching characteristics Example 1 5/6 / 0.5 / 1 / 87.5 28 ○ Example 2 15/6 / 0.5 / 1 / 77.5 60 ◎ Example 3 25/6 / 0.5 / 1 / 67.5 90 ◎ Example 4 40/6 / 0.5 / 1 / 52.5 150 ◎ Example 5 15/15 / 0.5 / 1 / 68.5 90 ◎ Example 6 15/30 / 0.5 / 1 / 53.5 170 ○ Example 7 15/6 / 0.1 / 1 / 77.9 55 ○ Example 8 15/6/5/1/73 50 ○ Example 9 15/6/10/1/68 55 △ Example 10 15/6 / 0.5 / 5 / 73.5 60 ◎ Example 11 15/6 / 0.5 / 10 / 68.5 60 ○ Example 12 20/10 / 0.5 / 5 / 64.5 50 ○ Comparative Example 1 3/6 / 0.5 / 1 / 89.5 X Not etched Comparative Example 2 50/6 / 0.5 / 1 / 42.5 200 X Comparative Example 3 25/0 / 0.5 / 1 / 73.5 X Not etched Comparative Example 4 15/35 / 0.5 / 1 / 48.5 300 X Comparative Example 5 15/6/0/1/78 30 Residue Comparative Example 6 15/6/12/1/66 70 Board Etched Comparative Example 7 15/6 / 0.5 / 0 / 78.5 65 Overhang Comparative Example 8 15/6 / 0.5 / 22 / 56.5 25 X ◎: Excellent 2) ○: Good 3) △: Normal 4) X: Poor

Table 6: Amorphous ITO Monolayer

Composition (wt%) (sulfuric acid / nitric acid / NH ₄ F / potassium acetate / water) Etch Speed (Å / sec) Etching characteristics Example 1 5/6 / 0.5 / 1 / 87.5 5.1 ○ Example 2 15/6 / 0.5 / 1 / 77.5 9.5 ◎ Example 3 25/6 / 0.5 / 1 / 67.5 10.0 ◎ Example 4 40/6 / 0.5 / 1 / 52.5 10.2 ◎ Example 5 15/15 / 0.5 / 1 / 68.5 9.5 ◎ Example 6 15/30 / 0.5 / 1 / 53.5 12.0 ◎ Example 7 15/6 / 0.1 / 1 / 77.9 6.5 ◎ Example 8 15/6/5/1/73 14.3 ◎ Example 9 15/6/10/1/68 14.3 ◎ Example 10 15/6 / 0.5 / 5 / 73.5 7.9 ◎ Example 11 15/6 / 0.5 / 10 / 68.5 8.0 ○ Example 12 20/10 / 0.5 / 5 / 64.5 10.4 ◎ Comparative Example 1 3/6 / 0.5 / 1 / 89.5 4.3 ○ Comparative Example 2 50/6 / 0.5 / 1 / 42.5 15.4 △ Comparative Example 3 25/0 / 0.5 / 1 / 73.5 X Not etched Comparative Example 4 15/35 / 0.5 / 1 / 48.5 14.5 △ Comparative Example 5 15/6/0/1/78 X Not etched Comparative Example 6 15/6/12/1/66 14.4 Board Etched Comparative Example 7 15/6 / 0.5 / 0 / 78.5 9.4 ○ Comparative Example 8 15/6 / 0.5 / 22 / 56.5 2.6 Residue ◎: Excellent 2) ○: Good 3) △: Normal 4) X: Poor

As can be seen from Table 1 to Table 6, it can be confirmed that when the etching using the metal film etching solution of the embodiment according to the present invention, it provides a good etching characteristics. In addition, when the etching solution of the comparative example outside the range of the component content in the composition of the present invention is used, it can be confirmed that the desired etching characteristics are not satisfied.

After etching the molybdenum monolayer with the metal film etching solution according to the present invention, the scanning electron micrograph (see FIG. 2) of the surface and the molybdenum / aluminum alloy double layer with the metal film etching solution according to the present invention were etched. Scanning electron micrographs (see FIG. 3) and indium oxide films etched with the metal film etching solution according to the present invention can also be confirmed through scanning electron micrographs (see FIG. 4). In other words, the center and the end portions of the molybdenum single layer, the center and the end portions of the molybdenum / aluminum alloy double layer, and the center and the end portions of the indium oxide film were observed in the entire substrate, respectively. As shown in FIGS. Can be.

In addition, the conventional etching solution composed of a compound of phosphoric acid, nitric acid and acetic acid has a high viscosity due to a high phosphoric acid content, and thus, the flowability of the etching solution is significantly reduced. Unlike the phenomenon in which a part is collected, the etching solution of the metal film according to the present invention may vary the etching rate from 30 kPa / sec to 180 kPa / sec (molybdenum / aluminum alloy double layer) by adjusting the composition ratio of each component. It can be adjusted and contains no phosphoric acid and has a low viscosity so that the liquidity of the etching solution is good and can be spread evenly throughout the substrate, thereby maintaining the etching uniformity and preventing the occurrence of stains due to the etching irregularity.

In addition, in the case of the conventional etchant consisting of phosphoric acid, nitric acid, and acetic acid compounds, the amount of the etchant released with the substrate is significantly increased, and the amount still remaining on the substrate even after the inclination equipment is introduced to prevent this from happening. Although present, the etchant has a viscosity of about 5 times lower than that of the phosphoric acid, nitric acid, and acetic acid compounds, so the fluidity on the substrate is very good. Meanwhile, the manufacturing process of an array substrate for a liquid crystal display device using the metal film etching solution according to the present invention will be described.

According to an aspect of the present invention, there is provided a method of manufacturing an array substrate for a liquid crystal display device using a metal film etching solution, the method including: (a) forming a metal layer on a substrate; (b) etching the metal layer to form a gate electrode; (c) forming a gate insulating layer on the gate electrode; (d) forming a semiconductor layer on the gate insulating layer; (e) forming source and drain electrodes on the semiconductor layer; (f) forming a pixel electrode on the source and drain electrodes.

Referring to Figures 1a to 1f, it will be described in detail as follows.

As shown in FIG. 1A, the metal layer 20 is deposited on the substrate 10 by sputtering, and then etched with a metal film etching solution according to the present invention. As shown in FIG. 1B, the gate electrode 20a is removed. Form. Here, the metal layer 20 to be deposited on the substrate 10 is preferably provided with a single film or a multilayer film provided with at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum and molybdenum alloy, in the present embodiment Although sputtering was used as a method of forming the 20 on the substrate 10, the present invention is not limited thereto.

As shown in FIG. 1C, a gate insulating layer 30 is formed by depositing silicon nitride (SiN _X ) on the gate electrode 20a formed on the substrate 10. Here, the gate insulating layer 30 is formed of silicon nitride (SiN _x ), but is not limited thereto. The gate insulating layer 30 may be formed using a material selected from various inorganic insulating materials including silicon oxide (SiO ₂ ). Can be formed.

The semiconductor layers 40 and 41 are formed on the gate insulating layer 30 by using chemical vapor deposition (CVD). That is, after the active layer 40 and the ohmic contact layer 41 are formed sequentially, a pattern is formed as shown in FIG. 1D through dry etching.

Here, the active layer 40 is generally formed of pure amorphous silicon (a-Si: H), and the ohmic contact layer 41 is formed of amorphous silicon (n ⁺ a-Si: H) containing impurities. When the active layer 40 and the ohmic contact layer 41 are formed, the chemical vapor deposition (CVD) method is described, but the present invention is not limited thereto.

Then, a metal layer is deposited on the ohmic contact layer 41 by sputtering and etched with a metal film etching solution according to the present invention to form a source electrode 50 and a drain electrode 51 as shown in FIG. 1E. . Here, the metal layer is preferably provided with a single film or a multilayer film provided with at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum and molybdenum alloy.

Inorganic insulating group or benzocyclobutene (BCB) and acryl (acryl) containing silicon nitride (SiN _x ) and silicon oxide (SiO ₂ ) on the entire surface of the substrate 10 on which the source electrode 50 and the drain electrode 51 are formed. After selecting the organic insulating material group including the resin-based resin (resin) to form an insulating film 60 in a single layer or a double layer, the indium oxide film [ITO (ITO) through the sputtering method on the entire surface of the substrate 10 is formed a transparent conductive material such as indium tin oxide (IZO) and indium zinc oxide (IZO)] is deposited and etched with the metal film etching solution according to the present invention to form a pixel electrode 70 as shown in FIG. 1F.

As described above, in the method of manufacturing an array substrate for a liquid crystal display device, when the metal film etching solution according to the present invention is used, the etching uniformity can be maintained even when the size of the substrate 10 is large, and staining can be prevented. The etching rate can be adjusted in various ways according to the composition ratio of the etching solution, and the amount of the etching solution released together with the substrate in the inclination equipment can be minimized.

As described above, in the case of etching a single film or a multilayer film formed of at least one selected from the group consisting of indium oxide film, aluminum, aluminum alloy, molybdenum and molybdenum alloy, the metal film etching solution according to the present invention has very good etching characteristics. Can be provided. Furthermore, in the case of using the metal film etching solution according to the present invention when manufacturing the array substrate for the liquid crystal display device, the etching rate can be freely adjusted by adjusting the composition ratio of each component, and the etching uniformity can be maintained even when the size of the substrate is large. It can prevent staining. In addition, the etching solution having the advantage of minimizing the loss of the liquid by lowering the viscosity for the problem that the amount of the etching liquid released with the substrate in the conventional etching solution is too large liquid loss to improve the fluidity on the substrate and An etching process can be achieved.

Claims (10)

Sulfuric acid at 5-40% by weight relative to the total weight of the composition; 0.5-30 weight percent nitric acid relative to the total weight of the composition; 0.1-10% by weight of halogen-based additives relative to the total weight of the composition; 0.5-20% by weight of organic acid or salt derived from organic acid relative to the total weight of the composition; The remaining component is a metal film etching solution, characterized in that it comprises water. The method according to claim 1, The halogen-based additive is HF, (NH ₄ ) F, (NH ₄ ) HF ₂ , KF, NaF, MgF ₂ , AlF ₃ , HCl, (NH ₄ ) Cl, KCl, NaCl, MgCl ₂ , FeCl ₃ , AlCl ₃ , HBr, (NH ₄ ) Br, KBr, NaBr, MgBr ₂ , AlBr ₃ , HI, (NH ₄ ) I, KI, NaI, MgI ₂ And AlI ₃ metal film etching solution, characterized in that selected from the group consisting of. The method according to claim 1, The organic acid has a carbon number of 5 or less and contains a carboxyl group, and the salt derived from the organic acid is in the group consisting of salts in which one or more hydrogens are substituted with ammonium ion, alkali metal ion or alkaline earth metal ion. Metal film etching solution, characterized in that selected. The method according to claim 1, The metal film etching solution further comprises one or more of an etching control agent, a surfactant, a metal ion blocking agent, a corrosion inhibitor and a pH control agent. The method according to claim 1, The metal film etching solution is used for etching a single film or a multi-layer film provided with at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum, molybdenum alloy and indium oxide film. The method according to any one of claims 1 to 5, A metal film etching solution, which is used for etching a multilayer or single metal film for forming a gate electrode, a source electrode, a drain electrode, and a pixel electrode of a TFT-LCD. (a) forming a metal layer on the substrate; (b) etching the metal layer to form a gate electrode; (c) forming a gate insulating layer on the gate electrode; (d) forming a semiconductor layer on the gate insulating layer; (e) forming source and drain electrodes on the semiconductor layer; (f) forming a pixel electrode on the source and drain electrodes, In at least one of the steps (b), (e) and (f), the liquid crystal display device array substrate is etched using the metal film etching solution according to any one of claims 1 to 4. Manufacturing method. The method according to claim 7, And the metal layer in step (b) is a single film or a multilayer film formed of at least one selected from the group consisting of aluminum, aluminum alloy, molybdenum and molybdenum alloy. The method according to claim 7, In the step (e), the source and the drain electrodes are formed by etching a single layer or a multilayer layer formed of at least one selected from aluminum, an aluminum alloy, molybdenum, and molybdenum alloy with the metal film etching solution. Method for manufacturing array substrate for device. The method according to claim 7, And (f) the pixel electrode is formed by etching an indium oxide film with the metal film etching solution.

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