KR20100027512A - Manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

PURPOSE: A manufacturing method of an array substrate for liquid crystal display is provided, which can be free from problem including electrical short, fault of wiring, and reduction of luminance etc. CONSTITUTION: A manufacturing method of an array substrate for liquid crystal display comprises a step of forming the gate wiring in the top of the substrate; a step of forming a gate isolation layer in the top of the substrate including the gate wiring; a step of forming a semiconductor layer on the gate isolation layer; a step of forming source and drain electrodes on the semiconductor layer; and a step of forming a pixel electrode connected to the drain electrode.

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. Resistance is a major factor that causes RC signal delay, especially for TFT LCD (thin film transistor liquid crystal display), which is a key factor in increasing panel size and realizing high resolution. Therefore, in order to realize the reduction of the RC signal delay, which is essential for the large-sized TFT LCD, low-resistance material development is essential, and chromium (Cr, specific resistance: 12.7 × 10-8 μm) and molybdenum (Mo), which have been mainly used in the past, are essential. , Resistivity: 5 x 10 < -8 > m, aluminum (Al, resistivity: 2.65 x 10 < -8 > m) and alloys thereof are difficult to use for gate and data wiring used in large-sized TFT LCDs.

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, the research on the copper-based metal film is separate, and various kinds are used as an etchant composition for the copper-based metal film, but they do not meet the performance required by the user.

Therefore, in the present invention, a taper profile having excellent linearity is formed when etching the copper-based metal film and no residue of the copper-based metal film is left, and the etching solution of the copper-based metal film capable of batch etching of the gate electrode and the gate wiring, the data electrode and the data wiring is possible. An object of the present invention is to provide a composition, 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 is based on the total weight of the composition

A) 5 to 30 weight percent hydrogen peroxide (H ₂ O ₂ );

B) 0.1 to 5% by weight of organic acid;

C) 0.1 to 5% by weight of a phosphate compound;

D) 0.1 to 5% by weight of a water soluble cyclic amine compound;

E) 0.1 to 5% by weight of a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule;

F) 0.01 to 1.0% by weight of a compound wherein fluorine ions dissociate in solution;

G) 0.01-5.0 wt% hydrogen peroxide decomposition inhibitor;

H) 0.001 to 4 weight percent of a surfactant; And

I) An etching liquid composition of a copper-based metal film containing a residual amount of water is provided.

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 etching solution composition of the present invention.

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) forming a pixel electrode connected to the drain electrode;

In the step a), after forming the copper-based metal film on the substrate, the gate wiring is formed by etching with the etchant composition of the present invention, and in the step d) after forming the copper-based metal film, the etchant with the etchant composition of the present invention The present invention provides a method of manufacturing an array substrate for a liquid crystal display device, wherein source and drain electrodes are formed.

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

Etching the copper-based metal film with the etchant composition according to the present invention forms a taper profile with excellent linearity and leaves no residue of the copper-based metal film, and thus can be free from problems such as electrical shorts, poor wiring, and reduced luminance. have.

In addition, since it is possible to collectively etch the gate electrode, the gate wiring, the data electrode and the data wiring using only the etchant composition according to the present invention, the process may be very simplified and the process yield may be maximized.

In addition, when using the etchant composition according to the present invention, it is possible to implement a large screen, high-brightness circuit using a low-resistance copper or copper alloy wiring and to manufacture an environmentally friendly semiconductor device.

The present invention relates to a composition comprising: A) hydrogen peroxide (H ₂ O ₂ ), B) organic acid, C) phosphate compound, D) water-soluble cyclic amine compound, E) water-soluble compound having nitrogen atom and carboxyl group in one molecule, F) in solution It relates to an etching liquid composition of a copper-based metal film comprising a compound in which fluorine ions are dissociated, G) hydrogen peroxide decomposition inhibitor, H) surfactant, and I) water.

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.

Hydrogen peroxide (H ₂ O ₂ ) is the main component for etching the copper-based metal film, the content is preferably 5 to 30% by weight based on the total weight of the composition. If the content of hydrogen peroxide is less than 5% by weight, the copper-based metal may not be etched or the etching rate is very slow, and if the content exceeds 30% by weight, it is difficult to control the process because the etching rate is overall faster.

The organic acid in the pH is appropriately adjusted (pH 0.5 ~ 4.5) serves to etch the copper-based metal film in the environment of the etching solution. Specific examples of organic acids include acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, and malonic acid. ), Pentanic acid (pentanoic acid), oxalic acid (oxalic acid) and the like, these may be used alone or in combination of two or more.

The content of the organic acid is preferably 0.1 to 5% by weight based on the total weight of the composition. If it is less than 0.1 wt%, it is difficult to maintain a pH of about 0.5 to 4.5 due to the lack of influence of adjusting the pH, and if it is more than 5.0 wt%, the etching rate of copper is increased and the etching rate of molybdenum or molybdenum alloy is slowed. (CD Loss) is increased and the likelihood of residue of molybdenum or molybdenum alloy is increased.

The phosphate compound is a component that makes the taper profile good. If no phosphate compounds are present, the etching profile may be poor. Various kinds of such phosphate compounds may be used, and it is preferable to use one selected from salts in which one or two hydrogens are substituted with an alkali metal or an alkaline earth metal in phosphoric acid. Specific examples include sodium phosphate, potassium phosphate, ammonium phosphate, and the like, which may be used alone or in combination of two or more.

The content of the phosphate compound is preferably 0.1 to 5% by weight with respect to the total weight of the composition, when less than 0.1% by weight may be a poor etching profile, when the content exceeds 5% by weight the problem of slowing the etching rate occurs Can be.

The water-soluble cyclic amine compound controls the etching rate of the copper-based metal and serves to increase the process margin by reducing the CD loss of the pattern. Specific examples include aminotetrazole, imidazole, indole, purine, pyrazole, pyridine, pyrimidine, pyrrole, pyrroly Pyrrolidine, pyrroline, and the like, and these may be used alone or in combination of two or more thereof.

The content of the water-soluble cyclic amine compound is preferably 0.1 to 5% by weight with respect to the total weight of the composition, if less than 0.1% by weight can be generated too large, and if more than 5% by weight of the etching rate of copper Because of the faster and slower etching rates of molybdenum or molybdenum alloys, it is possible to increase the seed loss and increase the likelihood of residuals of molybdenum or molybdenum alloys.

A water-soluble compound having a nitrogen atom and a carboxyl group in the molecule prevents the decomposition reaction of hydrogen peroxide that may occur during storage of the etchant composition and prevents the etching characteristics from changing when etching a large number of substrates. Specific examples include alanine, aminobutyric acid, glutamic acid, glycine, glycine, iminodiacetic acid, nitrilotriacetic acid, and sarcosine. These may be used alone or in combination of two or more.

The content of the water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is preferably 0.1 to 5% by weight. If less than 0.1% by weight, a passivation film is formed after etching a large amount of substrates (about 500 sheets) to provide sufficient process margin. When the copper molybdenum film or the copper molybdenum alloy film is increased, it is difficult to obtain the copper molybdenum film or the copper molybdenum alloy film because the etching speed of the copper is lowered and the etching rate of the molybdenum or molybdenum alloy is increased.

In general, an etching solution using hydrogen peroxide solution itself decomposes when stored, so that the storage period is not long and there is a risk that the container may explode. However, when a water-soluble compound having a nitrogen atom and a carboxyl group is included in one molecule, the decomposition rate of the hydrogen peroxide solution is reduced by nearly 10 times, which is advantageous for securing the storage period and stability. Particularly, in the case of the copper layer, when a large amount of copper ions remain in the etchant composition, a passivation film may be formed to oxidize black and then no longer etched, but the addition of the compound may prevent this phenomenon. .

The compound in which fluorine ions are dissociated in the solution serves to remove residues inevitably generated in a solution which simultaneously etches a copper film and molybdenum film. Various kinds may be used without particular limitation, and preferably ammonium fluoride, sodium fluoride, potassium fluoride, and the like, and their heavy fluoride compounds, that is, ammonium bifluoride, Compounds that can dissociate into fluoride ions or polyatomic fluoride ions in solution such as sodium bifluoride and potassium bifluoride can be used. The compounds may be used alone or in combination of two or more.

The content of the compound in which the fluorine ions are dissociated in the solution is preferably 0.01 to 1.0% by weight based on the total weight of the composition, and when the content is less than 0.01% by weight, an etching residue may occur, and when the content exceeds 1.0% by weight, the glass substrate is etched. There is a disadvantage that the rate is greatly generated.

The hydrogen peroxide decomposition inhibitor serves to assist the performance of the water-soluble compound having a nitrogen atom and a carboxyl group in the molecule, and serves to slow down the hydrogen peroxide decomposition rate. Hydrogen peroxide decomposition inhibitor is not particularly limited, various kinds can be used, for example, cyclohaxane amine can be used.

The content of the hydrogen peroxide decomposition inhibitor is preferably 0.01 to 5.0% by weight based on the total weight of the composition, if less than 0.01% by weight of the decomposition rate of the hydrogen peroxide degradation rate is lowered, if more than 5.0% by weight to slow the etching rate There is a disadvantage.

The surfactant plays a role of inversely decreasing the surface tension to increase the uniformity of etching. Such surfactants are preferably surfactants that can withstand etching solutions and are compatible. Examples thereof include any anionic, cationic, zwitterionic or nonionic, polyhydric alcohol type surfactant, and the like.

The amount of the surfactant is preferably 0.001 to 4% by weight based on the total weight of the composition, and when less than 0.001% by weight, the etching uniformity is lowered, and when the amount is more than 4% by weight, many bubbles are generated.

Although the said 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 kV / cm or more is preferably used.

In addition to the above components, a conventional additive may be further added to the etching liquid composition according to the present invention, and as the additive, a metal ion blocking agent, a corrosion inhibitor, or the like may be used.

In addition, the additive is not limited thereto, and in order to further improve the effects of the present invention, various other additives known in the art may be selected and added.

Hydrogen peroxide (H ₂ O ₂ ), organic acids, phosphate compounds, water-soluble cyclic amine compounds used in the present invention, water-soluble compounds having a nitrogen atom and a carboxyl group in one molecule, compounds in which fluorine ions dissociate in solution, hydrogen peroxide decomposition Compounds containing inhibitors and surfactants can be produced by commonly known methods, and preferably have a purity for semiconductor processing.

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 data 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) Etching method of the copper-based metal film comprising the step of etching the copper-based metal film using the etching liquid 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) forming a pixel electrode connected to the drain electrode;

In the step a), after forming the copper-based metal film on the substrate, the gate wiring is formed by etching with the etchant composition of the present invention, and in the step d) after forming the copper-based metal film, the etchant with the etchant composition of the present invention The present invention relates to a method for manufacturing an array substrate for a liquid crystal display device, wherein the source and drain electrodes are formed.

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.

Example  1 to 6

To the etchant composition of Examples 1 to 6 according to the composition shown in Table 1. Then, the etching process of the copper-based metal film (Cu single layer and Cu / Mo double layer) was performed using the etchant composition of Example 1.

During the etching process, the temperature of the etchant composition was about 30 ° C., and 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 by the above process was examined using a cross-sectional SEM (Model S-4700, manufactured by Hitachi). The measured etch rate indicated an appropriate rate, as shown in Table 1. In addition, as can be seen in Figures 1 and 2, the copper film etched with the etchant composition according to Example 1 showed a good etching profile, as can be seen in Figure 3, the copper as an etchant composition according to Example 1 When the membrane was etched, no etch residue 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.

H ₂ O ₂ / glycolic acid / imidazole / iminodiacetic acid / potassium phosphate / ammonium fluoride / cyclonucleic acid amine / polyethylene glycol / deionized water Etching Speed (Å / sec) Cu monolayer Cu / Mo Double Membrane Cu Mo One 5/2/1 / 0.5 / 0.5 / 0.1 / 0.5 / 1 / residual quantity 40 to 60 40 to 60 6 to 8 2 10/5/1 / 0.5 / 0.5 / 0.2 / 0.2 / 0.5 / balance 60 to 90 60 to 90 5 to 8 3 13 / 0.5 / 0.2 / 0.5 / 1 / 0.1 / 1/2 / balance 20 to 40 20 to 40 4 to 6 4 8/1/1 / 0.5 / 3 / 0.2 / 2/4 / residual quantity 40 to 60 40 to 60 6 to 8 5 22/2/2 / 0.5 / 1 / 0.3 / 0.3 / 0.1 balance 50 to 80 50 to 80 6 to 8 6 25/2/5/1/1 / 0.5 / 0.5 / 0.5 / 70 to 90 70 to 90 6 to 8

1 is a scanning electron microscope photograph of the etching cross-section after etching the copper film using the etchant composition according to Example 1 of the present invention,

FIG. 2 is a scanning electron micrograph of etching a copper layer using an etchant composition according to Example 1 of the present invention and then observing an overall etching profile. FIG.

3 is an electron scanning microscope photograph of the peripheral surface of the copper wiring to confirm that no etching residues remain after etching the copper film using the etchant composition according to Example 1 of the present invention.

Claims (15)

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; In step a), a copper-based metal film is formed on the substrate, and then, the gate wiring is formed by etching with an etchant composition. In step d), a copper-based metal film is formed, and then, the source and drain electrodes are etched with the etchant composition. Forming, The etchant composition is based on the total weight of the composition, A) 5 to 30% by weight of hydrogen peroxide (H ₂ O ₂ ), B) 0.1 to 5% by weight organic acid, C) 0.1 to 5% by weight phosphate compound, water-soluble cyclic amine 0.1 to 5% by weight of the compound, E) 0.1 to 5% by weight of a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, F) 0.01 to 1.0% by weight of a compound which dissociates fluorine ions in solution, G) Hydrogen peroxide decomposition inhibitor 0.01 To 5.0 weight percent, H) 0.001 to 4 weight percent of a surfactant; And I) a residual amount of water. The method of manufacturing an array substrate for a liquid crystal display device according to claim 1, wherein the array substrate for liquid crystal display device is a thin film transistor (TFT) array substrate. A) 5 to 30% by weight of hydrogen peroxide (H ₂ O ₂ ), B) 0.1 to 5% by weight of organic acid, C) 0.1 to 5% by weight of phosphate compound, D) 0.1 to 5 relative to the total weight of the etchant composition % By weight, E) 0.1 to 5% by weight of a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, F) 0.01 to 1.0% by weight of a compound which dissociates fluorine ions in solution, G) 0.01 to 5.0% by weight of hydrogen peroxide inhibitor , H) 0.001 to 4 weight percent of a surfactant; And I) a residual amount of water. The method of claim 3, wherein the organic acid is acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, glycolic acid, malonic acid ( malonic acid), pentanic acid (pentanoic acid), and oxalic acid (oxalic acid), the etching liquid composition of the copper-based metal film, characterized in that one or more selected from the group consisting of. The copper-based metal film of claim 3, wherein the phosphate compound is at least one selected from the group consisting of sodium sulfate, potassium phosphate and ammonium sulfate. Etch solution composition. The method of claim 3, wherein the water-soluble cyclic amine compound is aminotetrazole, imidazole, indole, purine, pyrazole, pyridine, pyrimidine ), Pyrrole (pyrrole), pyrrolidine (pyrrolidine) and pyrroline (pyrroline) is an etching liquid composition of the copper-based metal film, characterized in that one or more selected from the group consisting of. The method of claim 3, wherein the water-soluble compound having a nitrogen atom and a carboxyl group in one molecule is alanine, aminobutyric acid, glutamic acid, glycine (glycine), iminodiacetic acid, Nitrilotriacetic acid (nitrilotriacetic acid) and sarcosine (sarcosine), the etching liquid composition of the copper-based metal film, characterized in that one or more selected from the group consisting of. The copper according to claim 3, wherein the compound in which the fluorine ion is dissociated in the solution is one or two or more selected from the group consisting of NH ₄ FHF, KFHF, NaFHF, NH ₄ F, KF, and NaF. Etch solution composition of the metal film. The etchant composition of claim 3, wherein the hydrogen peroxide decomposition inhibitor is cyclohexane amine. 5. The etchant composition of claim 3, wherein the surfactant is one or two or more selected from anionic surfactants and polyhydric alcohol surfactants. The copper molybdenum film or molybdenum alloy layer and the molybdenum alloy layer according to any one of claims 3 to 10, wherein the copper-based metal film comprises a single film of copper or a copper alloy, a molybdenum layer and a copper layer formed on the molybdenum layer. It is a copper molybdenum alloy film containing the copper layer formed on the etching liquid composition of the copper-type metal 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) An etching method of the copper-based metal film comprising etching the copper-based metal film using the etching liquid composition of any one of claims 3 to 10. The method of claim 12, wherein the photoreactive material is a photoresist material, which is selectively left by an exposure and development process. The copper-based metal film according to claim 12 or 13, wherein the copper-based metal film includes a copper molybdenum film or a molybdenum alloy layer including a molybdenum layer and a copper layer formed on the molybdenum layer and a copper layer formed on the molybdenum alloy layer. Etching method of the copper-based metal film, characterized in that. An array substrate for a liquid crystal display device comprising at least one of a gate wiring and a source and a drain electrode etched by using the etching solution composition of claim 3.

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