TW201600647A - Etching solution composition for metal layer and manufacturing method of an array substrate for liquid crystal display using the same - Google Patents

Abstract

Disclosed herein is an etching solution composition comprising a metal layer oxidant; a chelating compound comprising unit represented by Chemical Formula 1 below; and water, wherein Ether value (D) of the etching solution composition, defined by Equation l below, is 0.2 ≤ D ≤ 2; and a manufacturing method of an array substrate for liquid crystal display using the composition: [Chemical Formula 1] R1-O-R2 [Equation 1] Ether value (D)=(A/B)*C*1,000.

Description

Etching liquid composition and method for manufacturing array substrate for liquid crystal display using same

The present invention relates to an etching liquid composition for a metal layer and a method of manufacturing an array substrate for a liquid crystal display using the foregoing etching liquid composition.

As flat screen displays such as LCDs, PDPs, and OLEDs, particularly TFT-LCDs, have become larger, a single layer composed of copper or a copper alloy has been widely reconsidered, or an alloy of copper or copper alloy/other metal or other metal is used. Or a plurality of layers of metal oxide greater than two layers in order to reduce wiring resistance and improve adhesion to the dielectric layer. For example, a copper/molybdenum layer, a copper/titanium layer, or a copper/molybdenum-titanium layer may be formed as a gate line of a TFT-LCD and a source/twist line constituting a data line, and may contribute to an enlarged display screen. Therefore, there is a need to develop a composition having excellent etching characteristics for etching these metal layers including a copper-based layer.

As the etching composition mentioned above, hydrogen peroxide and an amino acid etching liquid, hydrogen peroxide and a phosphoric acid etching liquid, hydrogen peroxide, a polyethylene glycol type etching liquid, or the like are generally used.

As an example, Korean Patent Application Publication No. 10-2011-0031796 discloses an etching solution comprising a water-soluble compound, having: A) hydrogen peroxide (H ₂ O ₂ ), B) persulfate, C) having an amine group and A soluble compound of a carboxyl group and water.

Korean Patent Application Publication No. 10-2012-0044630 discloses an etching solution for a copper-containing metal layer comprising: hydrogen peroxide, phosphoric acid, a cyclic amine compound, a sulfate, fluoroboric acid, and water.

Korean Patent Application Publication No. 10-2012-0081764 discloses an etching solution comprising: A) ammonium hydroxide, B) hydrogen peroxide, C) a fluorine compound, D) a polyol, and E) water.

However, in the aspect of CD loss, slope (taper), pattern straightness, metal residue, storage stability, and number of sheets to be processed of the metal layer containing the copper base layer, the above-mentioned etching liquid cannot be sufficiently satisfied. The conditions required in the related art.

(previous technical literature) (Patent Literature)

Patent Document 1: Korean Patent Application Publication No. 10-2011-0031796.

Patent Document 2: Korean Patent Application Publication No. 10-2012-0044630.

Patent Document 3: Korean Patent Application Publication No. 10-2012-0081764.

The present invention has therefore been devised to solve the above problems, and an object of the present invention is to provide an etching liquid composition having excellent work safety, excellent etching rate, and storage stability, and particularly excellent handling ability for a large number of sheets. An etchant composition; and a method of manufacturing an array substrate for a liquid crystal display using the composition.

In order to achieve the above object, an aspect of the invention provides an etching liquid composition comprising: a metal layer oxidizing agent; a chelating compound comprising a unit represented by the following Chemical Formula 1; and water, wherein the water is defined by the following formula 1 The aforementioned etching solution composition has an ether value (D) of 0.2. D 2.

[Chemical Formula 1] R ₁ -OR ₂

Wherein R ₁ and R ₂ are each independently hydrogen or a C1 to C4 hydrocarbon group, and R ₁ and R _{2 are} not hydrogen at the same time.

[Formula 1] Ether value (D) = (A/B) × C × 1,000

Here, A is 100 g of the mass of the chelate compound contained in the etching liquid composition; B is the molecular weight of the chelate compound; and C is the number of units of the chemical formula 1 contained in one molecule of the chelate compound.

Further, the present invention provides a method of manufacturing an array substrate for a liquid crystal display, comprising: a) a step of forming a gate on a substrate; b) a step of forming a gate insulator on a substrate including the gate; c) a step of forming a semiconductor layer on the gate insulator; d) a step of forming a source/drain on the semiconductor layer; and e) a step of forming a pixel electrode connected to the drain electrode; wherein the aforementioned steps a), d) or e) a step of forming a metal layer and etching the aforementioned metal layer with any of the aforementioned etching liquid compositions according to the invention to form an electrode.

The metal layer etching solution composition of the present invention can be obtained by containing an ether value of 0.2. D An amount of chelating compound of 2 provides the effect of processing a large number of substrates.

Further, as an embodiment of the present invention, the etching liquid composition for the metal layer containing the copper-based layer contains a low content of hydrogen peroxide, so it has the following advantages: excellent work safety, and economical disposal of the etching liquid The effect and provides an excellent etch rate. The present invention contains an ether value of 0.2 D The amount of the chelate compound of 2 also has excellent storage stability and excellent handling ability for a large number of sheets.

Further, the method of manufacturing an array substrate for a liquid crystal display using the etching liquid composition of the present invention can manufacture a liquid crystal display having excellent driving characteristics by forming an electrode having an excellent etching profile on an array substrate for a liquid crystal display. Array substrate.

The invention is described in detail below.

The present invention relates to an etching liquid composition comprising: a metal layer oxidizing agent; a chelating compound comprising a unit represented by the following Chemical Formula 1; and water, wherein the aforementioned etching liquid composition defined by the following Formula 1 The ether value (D) is 0.2 D 2.

[Chemical Formula 1] R ₁ -OR ₂

Wherein R ₁ and R ₂ are each independently hydrogen or a C1 to C4 hydrocarbon group, and R ₁ and R _{2 are} not hydrogen at the same time.

[Formula 1] Ether value (D) = (A/B) × C × 1,000

Here, A is 100 g of the mass of the chelate compound contained in the etching liquid composition; B is the molecular weight of the chelate compound; and C is the number of units of the above chemical formula 1 contained in one molecule of the chelate compound. .

The chemical formula 1 is a structural unit contained in the chelate compound, and the structural unit may be contained in the chemical structure of the chelate compound or at the end of the chelate compound. Thus, for example, when any of R ₁ and R ₂ is hydrogen or an alkyl group, it means that the chemical formula 1 is located at the end of the chelate compound.

The C1 to C4 hydrocarbon group may be an unsubstituted alkenyl group or an alkenyl group substituted with another substituent.

Chemical Formula 1, each unit comprising a chelate compound may share R ₁ and / or R ₂ with another unit of Chemical Formula 1.

If the ether value (D) in the etching solution composition is less than 0.2, the chelating ability of the metal ion in the etching liquid composition is insufficient; and if the ether value (D) exceeds 2, the above effect can no longer be expected to be enhanced. On the contrary, the etching rate is lowered due to an increase in the viscosity of the etching solution, so the ether value (D) is not preferable.

The metal layer oxidizing agent is not particularly limited, but may be selected from the group consisting of hydrogen peroxide, peracetic acid, oxidized metal, nitric acid, persulfate, halogen acid, and halogen acid salt. One or more of them.

Relative to the total weight of the foregoing composition, by containing 1% by weight to The etching liquid composition was prepared by using 40% by weight of the aforementioned metal layer oxidizing agent and the remaining amount of water.

In the case of a chelating compound, the amount of the chelating compound contained should satisfy the above range of the ether value (D).

The content of the metal layer oxidizing agent can be appropriately controlled depending on the type and characteristics of the oxidizing agent.

The oxidized metal means an oxidized metal such as Fe ³⁺ , Cu ²⁺ or the like, and it includes a compound which is dissociated into Fe ³⁺ , Cu ²⁺ or the like in a solution state. Persulfates include ammonium persulfate, alkali metal persulfate, oxone potassium hydride, and the like, and the acid salts include chlorates, perchlorates, bromates, perbromates, and the like.

The chelating compound containing the unit represented by Chemical Formula 1 of the present invention functions to increase the number of processed sheets by chelating metal ions (for example, copper ions) present in the etching liquid when the substrate is etched.

Representative examples of the chelating compound containing the unit represented by Chemical Formula 1 are a diol, a sugar, an ether group-containing compound, an ester group-containing compound, and a compound of the following chemical formula:

In the above chemical formula, n may be any value from 1 to 30; R, R ₁ and R ₂ are not particularly limited, but common examples thereof are hydrogen, a C1 to C5 alkyl group, an amine group, and a C6 to C12 aromatic hydrocarbon group. .

For diols, it is possible to use, without limitation, those known in the art. It is preferred to use polyethylene glycol.

As the polyethylene glycol, an additional polymer of ethylene oxide having a hydroxyl group or an ether group at the terminal may be used, but it is preferred to have at least one hydroxyl group. Further, the molecular weight is more preferably 1000 or less to suppress an excessive increase in the viscosity of the solution.

The sugar may be a monosaccharide, a disaccharide, a cyclodextrin or the like. The monosaccharide is, for example, glucose, and the disaccharide is, for example, sucrose.

The metal layer etched by the etching liquid composition of the present invention is not particularly limited, but the etching liquid composition of the present invention can be preferably used for etching a copper-based metal layer, a molybdenum-based metal layer, a titanium-based metal layer, or the like. The plural layers that make up.

The copper-based metal layer refers to a copper layer or a copper alloy layer, the molybdenum-based metal layer refers to a molybdenum layer or a molybdenum alloy layer, and the titanium-based metal layer refers to a titanium layer or a titanium alloy layer.

The plurality of layers include, for example, a double layer of a molybdenum-based metal layer/copper-based metal layer, wherein the copper-based metal layer is a lower layer and the molybdenum-based metal layer is an upper layer; and a copper-based metal layer/molybdenum-based metal layer is a double layer, wherein the molybdenum The metal layer is a lower layer and the copper-based metal layer is an upper layer; a copper-based metal layer/a double layer of a molybdenum-based and a titanium-based metal layer; and a plurality of layers of more than three layers, wherein the copper-based metal layer and the molybdenum-based metal layer are alternately laminated For example, a molybdenum-based metal layer/copper-based metal layer/molybdenum-based metal layer, or a copper-based metal layer/molybdenum-based metal layer/copper-based metal layer.

Further, the plurality of layers include, for example, a double layer of a titanium-based metal layer/a copper-based metal layer, wherein the copper metal layer is a lower layer and the titanium-based metal layer is an upper layer; and a copper-based metal layer/titanium-based metal layer is a double layer, wherein The titanium metal layer is a lower layer and the copper-based metal layer is an upper layer; and, a plurality of layers larger than three layers, wherein The copper-based metal layer and the titanium-based metal layer are alternately laminated, such as a titanium-based metal layer/copper-based metal layer/titanium-based metal layer, or a copper-based metal layer/titanium-based metal layer/copper-based metal layer.

The inter-layer combination structure of the plurality of layers can be determined by considering the materials constituting the upper layer or the lower layer or the adhesion to the respective layers.

The copper, molybdenum or titanium alloy layer refers to a metal layer which is made of an alloy in which copper, molybdenum or titanium is a main component and other different metals are used depending on the film properties. For example, a molybdenum alloy layer refers to a layer made of an alloy, for which molybdenum is a main component and contains titanium (Ti), tantalum (Ta), chromium (Cr), nickel (Ni), niobium (Nd), and One or a plurality of indium (In).

The etching liquid composition of the present invention may further comprise one or more selected from the group consisting of a nitrogen atom-containing compound, a fluorine compound, and an acid containing a sulfur atom (S) or a phosphorus atom (P).

The nitrogen atom-containing compound contained in the etching liquid composition of the present invention is used to enhance the etching rate of the etching liquid composition and the number of sheets processed.

A nitrogen atom-containing compound known in the art can be used without limitation, and a compound containing an amine group and a carboxylic acid group in the molecule can be typically used.

The compound containing an amine group and a carboxylic acid group in the molecule may include, for example, an α-amino acid having one carbon atom between a carboxylic acid group and an amine group, and typically includes a monovalent amino acid such as glycine. Acid, glutamic acid, glutamine, isoleucine, valine, tyrosine, arginine, etc.; and polyvalent amino acids such as iminodiacetic acid, nitrilotriacetic acid, B Glycoltetraacetic acid. The nitrogen atom-containing compound may be used singly or in combination of two or more kinds. use.

The content of the nitrogen atom-containing compound may be from 0.1% by weight to 10% by weight, preferably from 1% by weight to 5% by weight, based on the total weight of the composition. Since the above range can increase the etching rate of the etching liquid and the number of sheets to be processed, the above range is preferable.

The fluorine compound contained in the etching liquid composition of the present invention is used for removing etching residues and for etching a titanium-based metal layer.

The fluorine compound may be included in an amount of from 0.1% by weight to 5% by weight, based on the total weight of the composition, preferably from 0.1% by weight to 2% by weight.

The above range is preferable because the etching residue can be prevented and the etching of the glass substrate or the underlying layer is not caused.

However, if the above range is exceeded, stains are generated in the substrate due to uneven etching characteristics, an excessively fast etching speed may damage the lower layer, and etching rate control may become difficult during this step.

Preferably, the fluorine compound may be a compound capable of dissociating into a fluoride ion or a polyatomic fluoride ion.

The compound capable of dissociating into a fluoride ion or a polyatomic fluoride ion may be at least one selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, sodium hydrogen fluoride, and potassium hydrogen fluoride.

The content of the acid containing a sulfur atom (S) or a phosphorus atom (P) may be from 0.01% by weight to 10% by weight, and preferably from 0.01% by weight to 1% by weight, based on the total weight of the composition.

When the amount of the acid satisfies the above range, the intended function can be performed because the acid caused by the sulfur atom (S) or the phosphorus atom (P) can be avoided. The metal layer is at risk of over etching and underlying etching, and does not cause a problem that the etching rate of the copper metal layer is lowered due to the acid content of the sulfur atom (S) or the phosphorus atom (P) being too low.

For the acid containing a sulfur atom (S) or a phosphorus atom (P), any component known in the art such as sulfuric acid, sulfonic acid, phosphoric acid, phosphonic acid or the like can be used without particular limitation, and phosphoric acid is particularly preferably used. . Phosphoric acid promotes the etching of copper by hydrogen peroxide by supplying hydrogen ions to the etching solution. In addition, the formation of phosphate in combination with the oxidized copper ions increases the solubility in water and eliminates the metal layer residue after etching.

The water used in the present invention means deionized water, water used for semiconductor processing, and water of more than 18 M?/cm is preferably used.

The etching liquid composition of the present invention may further include one or more selected from the group consisting of an etching control agent, a surfactant, a metal ion shielding agent, a corrosion inhibitor, and a pH adjusting agent, in addition to the components mentioned above.

As a specific embodiment of the etching liquid composition of the present invention, hydrogen peroxide can be used as the metal layer oxidizing agent, and in addition to the chelate compound represented by Chemical Formula 1 and water, a compound containing a nitrogen atom can be further included.

Further, the etching liquid composition of the present invention may further comprise one or more selected from the group consisting of a fluorine compound and an acid containing a sulfur atom (S) and a phosphorus atom (P).

Specifically, the etchant composition is preferably used for etching a copper-based metal layer, a copper-based metal layer/molybdenum-based metal layer or a copper-based metal layer/titanium-based metal layer. However, the application of the composition is not limited to the above layers.

Hydrogen peroxide is a main component for oxidizing copper, molybdenum and titanium, and the amount of hydrogen peroxide may be from 1% by weight to 25% by weight, preferably from 1% by weight to 10% by weight, based on the total weight of the composition. More preferably, it is 1% by weight to 5% by weight.

When the amount of hydrogen peroxide falls within the above range, the etching rate of copper, molybdenum, and titanium is prevented from being deteriorated, an appropriate amount of etching can be achieved, and an excellent etching profile can be obtained.

However, if it is outside the above range, etching does not occur or excessive etching occurs, and thus pattern loss and loss of function as a metal wiring may occur.

The components constituting the etching liquid composition of the present invention preferably have a purity for semiconductor processing.

Further, the present invention relates to a method of manufacturing an array substrate for a liquid crystal display, comprising: a) a step of forming a gate on a substrate; b) a step of forming a gate insulator on a substrate including the gate; a step of forming a semiconductor layer on the gate insulator; d) a step of forming a source/drain on the semiconductor layer; and e) a step of forming a pixel electrode connected to the drain; wherein the aforementioned steps a) and d Or e) comprising the step of forming a metal layer and etching the aforementioned metal layer using the etching liquid composition according to the present invention to form an electrode.

The array substrate for a liquid crystal display produced by the above method has excellent driving characteristics according to an electrode including an excellent etching profile.

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

Hereinafter, the present invention will be described in more detail by the following embodiments. However, the following examples are intended to explain the present invention in more detail, and the scope of the invention is not limited by the following examples. Those skilled in the art can appropriately modify the following embodiments within the scope of the invention.

(Example) Example 1 to Example 10 and Comparative Example 1 to Comparative Example 10:

An etchant composition was prepared by mixing the components having the contents shown in Table 1 below.

Experimental Example 1. Evaluation of etching profile of etching solution composition (1) Evaluation of etching rate of Cu single layer

The Cu single layer was etched using the etching liquid compositions of Examples 1 to 3 and Comparative Examples 1 to 3. When the etching step was performed, etching was performed for 100 seconds using an etching liquid composition having a temperature of about 30 °C. EPD (end point detection, metal etch timing) was measured with the naked eye to obtain an etch rate according to time. The profile profile of the etched Cu monolayer was examined by using SEM (Hitachi Co., model S4700), and the results are shown in Table 2 below.

(2) Evaluation of the etching rate of the Cu/Mo-Ti double layer

Etching of the Cu/Mo-Ti double layer was performed using the etching liquid compositions of Examples 4 to 8 and Comparative Examples 4 to 8. When the etching step was performed, etching was performed for 100 seconds using an etching liquid composition having a temperature of about 30 °C. EPD (end point detection, metal etch timing) was measured with the naked eye to obtain an etch rate according to time. The profile cross section of the etched Cu/Mo-Ti bilayer was examined by using SEM (Hitachi Co., model S4700), and the results are shown in Table 2 below.

Experimental Example 2. Evaluation of the number of sheets processed

A reference test was conducted by using the etching liquid compositions of Examples 1 to 10 and Comparative Examples 1 to 4, and 4,000 ppm of copper was used. The powder was added to the etchant for this reference test and completely dissolved. Thereafter, the reference test was again performed by etching, and the reduction ratio of the etching rate was evaluated.

<Evaluation criteria>

○: Excellent (the reduction rate of the etching rate is less than 10%),

△: good (the reduction rate of the etching rate is 10% to 20%),

×: Poor (the reduction ratio of the etching rate exceeds 20%).

As demonstrated in Table 2 above, according to various embodiments of the present invention The etchant compositions all exhibited excellent etch rates and the number of sheets processed. However, the etching liquid composition of the comparative example exhibited inferior properties in terms of the number of sheets processed.

On the other hand, for Comparative Examples 9 and 10, the results of the number of sheets processed were excellent due to the high ether value (D), but these results indicate that the etching rate was remarkably lowered.

Claims (9)

An etching liquid composition comprising: a metal layer oxidizing agent; a chelating compound comprising a unit represented by the following Chemical Formula 1; and water; wherein the aforementioned etching liquid composition defined by the following Formula 1 has an ether value (D) of 0.2 D 2; [Chemical Formula 1] R ₁ -OR ₂ ; wherein R ₁ and R ₂ are each independently hydrogen or a C1 to C4 hydrocarbon group, and R ₁ and R _{2 are} not hydrogen at the same time; [Formula 1] Ether value (D) = (A/B) × C × 1,000; wherein A is 100 g of the mass of the aforementioned chelating compound contained in the etching solution composition; B is the molecular weight of the aforementioned chelate compound; and C is in one molecule of the aforementioned chelate compound The number of units of the aforementioned Chemical Formula 1 contained. The etching liquid composition according to claim 1, wherein the metal layer oxidizing agent is one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, hydrohalic acid, and hydrohalide. Multiple species. The etching solution composition according to claim 1, wherein the chelate compound is one or more selected from the group consisting of a diol, a sugar, an ether group-containing compound, and an ester group-containing compound. The etching liquid composition according to claim 1, comprising: 1% by weight to 40% by weight of the metal layer oxidizing agent based on the total weight of the composition; the amount of the chelate compound is defined by the following formula 1 The aforementioned etching solution composition has an ether value (D) of 0.2. D 2; and the remaining amount of water. The etching liquid composition according to claim 4, which further comprises one or more selected from the group consisting of 0.1% by weight to 10% by weight of a nitrogen atom-containing compound; 0.1% by weight to 5% by weight Fluorine compound; 0.01% by weight to 10% by weight of an acid containing a sulfur atom or a phosphorus atom. The etching liquid composition according to claim 5, wherein the metal layer oxidizing agent comprises 1% by weight to 25% by weight of hydrogen peroxide; the nitrogen atom-containing compound is an amino acid; and the aforementioned sulfur atom or phosphorus atom The acid is phosphoric acid. The etching liquid composition according to claim 1, wherein the etching liquid composition is used for etching a copper-based metal layer, a molybdenum-based metal layer, a titanium-based metal layer, or a plurality of layers. The etching liquid composition according to claim 7, wherein the plurality of layers are a copper-based metal layer/molybdenum-based metal layer or a copper-based metal layer/titanium-based metal layer. A method of manufacturing an array substrate for a liquid crystal display, comprising: a) a step of forming a gate on a substrate; b) a step of forming a gate insulator on a substrate including the gate; c) forming a semiconductor on the gate insulator a step of forming a layer; d) a step of forming a source/drain on the aforementioned semiconductor layer; e) a step of forming a pixel electrode connected to the aforementioned drain electrode; wherein the aforementioned step a), d) or e) comprises forming a metal layer and etching the foregoing using the etching liquid composition as recited in any one of claims 1 to 6 The step of forming a metal layer to form an electrode.