TW201600642A - 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 agent; and remainder of water, wherein the amount of mol for functional group of the chelating agent, compared with the amount of mol for the metal layer oxidant, is 0.1 to 10, and a manufacturing method of an array substrate for liquid crystal display using the composition.

Description

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

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

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 carboxyl soluble compounds 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 is therefore designed to solve the above problems, and an object of the present invention is to provide an etching liquid composition having excellent work safety, an excellent etching rate, and a capability of processing a large amount of sheets, and specifically an optimum etching having an excellent etching rate. An etchant composition having a contour and an excellent ability to handle a large number of sheets; and an array base for a liquid crystal display using the composition Board method.

In order to achieve the above object, an aspect of the present invention provides an etching liquid composition comprising: a metal layer oxidizing agent, a chelating agent, and a remaining amount of water, wherein a molar amount of a functional group of the foregoing chelating agent The molar amount of the oxidizing agent is 0.1 to 10, and the functional group of the aforementioned chelating agent is a unit having a hetero atom on both sides of the β-position, and the molar amount of the aforementioned metal layer oxidizing agent and the function of the aforementioned chelating agent The molar amount of the base is obtained from Equation 1 and Equation 2 below:

Another aspect of the present invention provides a method of fabricating 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 said gate insulator; d) a step of forming a source/drain on said semiconductor layer; and e) a step of forming a picture electrode connected to said gate; wherein said step a) d) or e) includes the 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 etchant composition of the present invention can provide an excellent etching rate and a large number of sheets to be processed by adjusting the functional groups of the chelating agent.

Further, as an embodiment of the present invention, for example, a copper base layer is included The metal layer etching solution composition contains a low content of hydrogen peroxide as an oxidizing agent, and thus has an excellent work safety, a price competitive advantage, and an effect of economically disposing the etching liquid.

Further, a 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 etchant composition comprising: a metal layer oxidizing agent, a chelating agent, and a remaining amount of water; wherein the chelating agent has a molar amount of a functional group compared to the aforementioned metal layer oxidizing agent The amount of the ear is 0.1 to 10, and the functional group of the aforementioned chelating agent is a unit having a hetero atom on both sides of the β-position, and the molar amount of the aforementioned metal layer oxidizing agent and the molar amount of the functional group of the aforementioned chelating agent are from below Equation 1 and Equation 2 are obtained.

In the present invention, the chelating agent is compared with the molar amount of the metal layer oxidizing agent. The molar amount of the functional group is defined as the "chelating concentration", and the etching solution composition has a chelate concentration of 0.1 to 10. The chelating concentration can be appropriately adjusted depending on the type and characteristics of the oxidizing agent. If the value of the chelating concentration is from 0.1 to 10, excellent etching properties such as an excellent etching rate and an excellent number of sheets to be processed, and the like can be exhibited.

If the chelating concentration is less than 0.1, there is a problem that the amount of the sheet to be treated is lowered due to the lack of stabilization of the dissolved metal oxide; and if the chelating concentration exceeds 10, there is a problem that the etching rate is lowered due to an increase in viscosity. .

The metal layer oxidizing agent is a main component for oxidizing the metal layer, and is not particularly limited, but may be typically selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxides, nitric acid, persulfates, hydrohalic acids, and halogenates. One or more of the group consisting of.

The oxidized metal means an oxidized metal such as, for example, 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 etchant composition can be made by comprising from 1% to 40% by weight, based on the total weight of the composition, of a metal layer oxidant, from 0.1% to 10% by weight of a chelating agent and the balance of water.

The content of the metal layer oxidizing agent can be appropriately adjusted according to the type and characteristics of the oxidizing agent, and when the metal layer oxidizing agent is contained within the above range, the etching rate of the metal layer can be appropriately adjusted.

As the chelating agent, ethylene glycols are preferred, and components known in the art can be used without limitation, and polyethylene glycol is particularly preferably used.

As the polyethylene glycol, an addition polymer of ethylene oxide having a hydroxyl group or an ether group at the terminal can 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 chelating agent is present in an amount of from 0.1% by weight to 10% by weight, based on the total weight of the composition, preferably from 1% by weight to 5% by weight. If the chelating agent is contained in an amount of less than 0.1% by weight, it is difficult to expect an increase in the number of sheets to be processed of the substrate, and there is a possibility that the etching uniformity is lowered and the decomposition of the metal layer oxidizing agent is accelerated. Further, when the content exceeds 10% by weight, the disadvantage of generating a large amount of foam may be caused.

The metal layer etched by the etching liquid composition of the present invention is not particularly limited, but a copper-based metal layer, a molybdenum-based metal layer, a titanium-based metal layer or the like is preferably used.

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 molybdenum-based layer and a titanium-based alloy 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; a copper-based metal layer/a titanium-based metal layer and a double layer of a molybdenum-based alloy layer; and a plurality of layers greater than three layers, wherein the copper-based metal layer and the titanium-based metal The layers 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 layers.

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

The etching liquid composition of the present invention may further comprise one or more selected from the group consisting of a fluoride, a nitrogen atom-containing compound, and phosphoric acid.

The fluoride 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 fluoride content may be from 0.1% by weight to 5% by weight, more preferably from 0.1% by weight to 2% by weight, based on the total weight of the composition.

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 it is outside the above range, stains are generated in the substrate due to uneven etching characteristics, and an excessively fast etching speed may damage the lower layer, and And etch rate control can become difficult during processing.

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

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 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 to be processed.

As the nitrogen atom-containing compound, 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 the carboxylic acid and the amine group, and typically includes a monovalent amino acid such as glycine , glutamic acid, glutamine, isoleucine, valine, tyrosine, arginine, etc.; and polyvalent amino acids, such as iminodiacetic acid, nitrilotriacetic acid, ethylene Alcoholic acid.

The nitrogen atom-containing compound may be used singly or in combination of two or more.

The content of the nitrogen atom-containing compound may be from 0.1% by weight to 10% by weight, and preferably from 1% by weight to 5% by weight, based on the total weight of the composition.

If the nitrogen atom-containing compound is included in the above range, the etching rate of the etching liquid and the number of sheets to be processed can be increased.

Phosphoric acid promotes oxidation by a metal layer by supplying hydrogen ions to the etching solution The agent etches copper. In addition, the solubility in water is increased by the combination of oxidized copper ions to form a phosphate, and the metal layer residue after etching is eliminated.

The content of phosphoric acid 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 phosphoric acid satisfies the above range, the intended function can be performed because the risk of over-etching and underlying corrosion of the metal layer by phosphoric acid can be avoided, and the etching rate of the copper metal layer is not lowered due to too low phosphoric acid content. The problem.

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 at least one selected from the group consisting of an etching control agent, a surfactant, a chelating agent, a corrosion inhibitor, and a pH adjusting agent, in addition to the above-mentioned constituent components.

As an embodiment of the present invention, hydrogen peroxide may be used as the metal layer oxidizing agent, and in addition to the chelating agent and water, one or more kinds selected from the group consisting of a fluoride, a nitrogen atom-containing compound, and phosphoric acid may be additionally contained. .

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

Hydrogen peroxide is a main component of copper oxide, molybdenum and titanium, and hydrogen peroxide having a concentration of more than 0 and 10% or less is preferably used. Further, the amount of hydrogen peroxide may be from 1% by weight to 25% by weight, preferably more than 1% by weight and less than or equal to 10, relative to the total weight of the composition. % by weight, more preferably more than 1% by weight and less than or equal 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.

Further, for the nitrogen atom-containing compound, an amino acid is preferably used.

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 picture electrode connected to the drain; wherein the aforementioned steps a), 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 electrode having 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 present invention.

(Example)

Examples 1 to 6 and Comparative Examples 1 to 3:

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

Etching of the Cu single layer was performed using the etching liquid compositions of Examples 1 to 4 and Comparative Example 1. When etching is performed, etching is performed for 100 seconds using an etching liquid composition having a temperature of about 30 °C. The EPD (end point detection, metal etch timing) was measured with the naked eye to obtain an etch rate (etching rage) according to time. The profile cross section of the etched Cu single layer was examined by using SEM (Hitachi Co., Model S4700), and the results are shown in Table 2 below. in.

(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 5 to 6 and Comparative Examples 2 to 3. When the etching treatment was performed, etching was performed for 100 seconds using an etching liquid composition having a temperature of about 30 °C. The EPD (end point detection, metal etch timing) was measured with the naked eye to obtain an etch rate (etching rage) 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 to be 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 powder was added to the etching liquid for the 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%).

Claims (9)

An etchant composition comprising: a metal layer oxidizing agent, a chelating agent and a remaining amount of water; wherein the molar amount of the functional group of the chelating agent is 0.1 to 10 compared to the molar amount of the metal layer oxidizing agent; The functional group of the mixture is a unit having a hetero atom on both sides of the β-position; and the molar amount of the aforementioned metal layer oxidizing agent and the molar amount of the functional group of the aforementioned chelating agent are obtained from the following Equations 1 and 2: 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 oxides, nitric acid, persulfates, hydrohalic acids, and hydrohalides. Or a plurality of species. The etching solution composition according to claim 1, wherein the total weight of the composition comprises: 1% by weight to 40% by weight of the aforementioned metal layer oxidizing agent; 0.1% by weight to 10% by weight of the aforementioned chelating agent; The remaining amount of water. The etching liquid composition according to claim 3, further comprising an extruding agent One or more of the group consisting of 0.1% by weight to 5% by weight of fluoride; 0.1% by weight to 10% by weight of a nitrogen atom-containing compound; and 0.01% by weight to 10% by weight of phosphoric acid. The etching liquid composition according to claim 4, wherein the metal layer oxidizing agent contains hydrogen peroxide. 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 with respect to the total weight of the foregoing composition; and the aforementioned nitrogen atom-containing compound is an amino 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, a copper-based metal layer/titanium-based metal layer or a copper-based metal layer/molybdenum-titanium-based alloy 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 source/drain on the semiconductor layer; and e) a step of forming a picture electrode connected to the drain; wherein the aforementioned step a), d) or e) comprises forming a metal layer And etching using the etching liquid composition as described in any one of claims 1 to 8. The step of forming the electrode by the aforementioned metal layer.