TW201600641A - 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 containing a metal layer oxidant, a compound having both of amino acid group and polyethylene glycol group in molecule, and water; 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 an etching liquid composition for a metal layer and a method of manufacturing an array substrate for a liquid crystal display using the same.

As flat panel displays such as LCDs, PDPs and OLEDs, in particular TFT-LCDs, have become larger, a single layer consisting of copper or a copper alloy has been widely reinstated, or copper or copper alloys/other metals, alloys of other metals or A plurality of layers of metal oxide are larger than two layers 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 can be formed as a gate line of a TFT-LCD and source/汲 wiring constituting a data line, and can contribute to an enlarged display screen. Therefore, there is a need to develop compositions having excellent etching characteristics for etching these metal layers of a copper-containing 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, for the copper-containing metal layer, the above-mentioned etching liquid is insufficient to satisfy the CD loss, the slope (taper), the pattern straightness, the metal residue, the storage stability, and the number of sheets to be processed. 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 made to solve the above problems, and an object of the present invention is to provide an etching liquid composition which has excellent work safety, storage stability, particularly excellent etching rate and excellent handling ability for a large number of sheets. And providing 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 compound containing a metal layer oxidizing agent; a compound having both an amino acid group and a polyethylene glycol group in a molecule; and water.

Another aspect of 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 the 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 source/drain; wherein, step a), d) or e) includes 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 metal layer etching solution composition of the present invention provides an advantage that the etching rate is increased and a large number of substrates can be processed by including a compound having both an amino acid group and a polyethylene glycol group in the molecule.

Further, as an embodiment of the present invention, an etching liquid composition for a metal layer containing a copper-based layer contains a low content of hydrogen peroxide, and thus has the advantages of excellent work safety, price competitiveness, and economical disposal. The effect of the etching solution. Further, it provides the ability to handle a large number of substrates and excellent storage stability.

Further, a method of manufacturing an array substrate for a liquid crystal display using the etching liquid composition of the present invention enables an array substrate for a liquid crystal display An electrode having an excellent etching profile is formed thereon to fabricate an array substrate for a liquid crystal display having excellent driving characteristics.

The invention is described in detail below.

The present invention relates to an etching liquid composition comprising: a metal layer oxidizing agent; a compound having both an amino acid group and a polyethylene glycol group in a molecule; and water.

A compound having both an amino acid group and a polyethylene glycol group in the molecule can be represented by Chemical Formula 1:

In the formula, R ₁ and R ₂ are each independently hydrogen or a C1 to C8 linear or branched alkyl group, and R ₁ and R ₂ are bonded to each other to form a C4 to C10 cycloalkyl group, and R ₁ and R ₂ forming an amine group-containing C4 to C10 heterocyclic ring by binding to an amine group; R ₃ is hydrogen or a C1 to C8 linear or branched alkyl group; and n is a natural number from 1 to 20.

The metal layer oxidizing agent used as a main component of the oxidized metal layer is not particularly limited, but may typically include a solvent selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxides, nitric acid, persulfates, hydrohalic acids, and halogenates. At least one of the group consisting of.

The oxidized metal means an oxidized metal such as Fe ³⁺ , Cu ²⁺ or the like, and 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.

A compound having both an amino acid group and a polyethylene glycol group in the molecule has a combined structure of an amino acid and a polyethylene glycol.

Therefore, the etching rate of the metal layer becomes faster, and the number of processed substrate sheets is also increased. The storage stability of the etching solution is also improved.

In the definition of R ₁ to R ₃ of Chemical Formula 1, the linear or branched alkyl group of C1 to C8 is preferably a methyl group, an ethyl group, a propyl group or a butyl group, and the C4 to C10 cycloalkyl group is preferably a C5 ring. Alkyl or C6 cycloalkyl.

The n of the chemical formula 1 is more preferably a natural number of 2 to 10.

The etchant composition can be prepared by including the following composition: 1 wt% to 40 wt% of the metal layer oxidant relative to the total weight of the composition; 1 wt% to 10 wt% of the amino acid group and the poly group in the molecule a compound of an ethylene glycol group; and the remaining amount of water.

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

The amount of the compound having both an amino acid group and a polyethylene glycol group in the molecule is more preferably from 2% by weight to 5% by weight. If its amount is less than 1% by weight, it is difficult to expect an increase in the etching rate and the number of processed substrate sheets. Further, if it exceeds 10% by weight, it is difficult to expect such an effect to still increase, and more specifically, the etching rate is lowered due to an increase in viscosity, and thus it is not preferable.

The etching liquid composition of the present invention can be used regardless of the type of layer to be etched, but is more preferably used for etching a copper-based metal layer, a molybdenum-based metal layer, a titanium-based metal layer, or a plurality of layers composed of these layers.

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: a double layer of, for example, a molybdenum-based metal layer/a 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 alloy layer; and a plurality of layers larger than three layers, wherein the copper-based metal layer and the molybdenum-based metal layer are laminated to each other, 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 double-layered, wherein a titanium metal layer is a lower layer and a copper-based metal layer is an upper layer; and a plurality of layers greater than three layers, wherein the copper-based metal layer and the titanium-based metal layer are laminated to each other, such as a titanium-based metal layer/a copper-based metal layer/a titanium-based metal Layer, or 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 alloy layer, the molybdenum alloy layer or the titanium alloy layer refers to a metal layer produced as an alloy in which copper, molybdenum or titanium is a main constituent and other different metals are used depending on the film properties. For example, a molybdenum alloy layer refers to molybdenum as a main component and contains titanium (Ti), tantalum (Ta), chromium (Cr), A layer produced by one or a plurality of alloys of nickel (Ni), niobium (Nd), and indium (In).

The etching liquid composition of the present invention may further include at least one selected from the group consisting of a fluorine compound and an acid containing a sulfur (S) atom or a phosphorus (P) atom.

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

The amount of the fluorine compound may be from 0.1% by weight to 5% by weight, preferably from 0.1% by weight to 2% by weight based on the total weight of the composition. More preferably, the above range is because etching residue can be prevented and etching of the glass substrate or the underlying germanium layer is not caused.

However, if the amount of the fluorine compound exceeds the above range, the stain is generated in the substrate due to the uneven etching characteristics, the layer is damaged due to the excessive etching rate, and it is difficult to control the etching rate during the process.

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 one or a plurality selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, sodium hydrogen fluoride, and potassium hydrogen fluoride.

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

When the amount of the above acid satisfies the above range, the intended function can be exerted because the risk of excessive etching of the metal layer and corrosion of the underlying layer caused by phosphoric acid can be avoided, and the etching rate of the copper metal layer due to too low an acid content is not caused. The problem of getting lower.

As the acid containing a sulfur (S) atom or a phosphorus (P) atom, any constituent known in the art can be used without limitation, such as sulfuric acid, sulfonic acid, phosphoric acid, phosphonic acid, etc., 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 for semiconductor processing, and preferably more than 18 M?/cm.

In addition to the above-mentioned constituents, the etching liquid composition of the present invention may further comprise one or more selected from the group consisting of an etching control agent, a surfactant, a metal ion chelating agent, a corrosion inhibitor, and a pH adjusting agent.

As an embodiment of the present invention, hydrogen peroxide can be used as the metal layer oxidizing agent, and a fluorine compound can be additionally contained in addition to the compound having both an amino acid group and a polyethylene glycol group in the molecule and water.

Further, an acid containing a sulfur (S) atom or a phosphorus (P) atom may also be included.

Specifically, the above etching liquid 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 use of the above composition is not limited to the above layers.

Hydrogen peroxide is a main component for oxidizing copper, molybdenum and titanium, and may be in an amount of 1% by weight to 25% by weight, preferably 1% by weight to 10% by weight, more preferably 1% by weight based on the total weight of the composition. %~5wt%. 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 over-etching may occur, so pattern loss and loss of function as a metal wiring may occur.

The composition constituting the etching liquid composition of the present invention preferably has 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 a gate; c) a gate insulator a step of forming a semiconductor layer; 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 step a), d) or e) comprises forming a metal layer And the step of etching the 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 because it includes an electrode having an excellent etching profile.

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

In the following, the invention will be described in more detail by means of the embodiments provided. However, the following examples are intended to illustrate the invention in more detail, and the scope of the invention is not limited by the following examples. The following embodiments are appropriately modified by those skilled in the art within the scope of the invention.

(Example) Examples 1 to 10 and Comparative Examples 1 to 4: Preparation of Etching Liquid Composition

The composition was mixed by the contents described in Table 1 below and an etchant composition was prepared.

Experimental Example 1: Evaluation of Etching Profile of Etching Solution Composition (1) Evaluation of Cu single layer etch rate

Etching of the Cu single layer was performed using the etching liquid compositions of Examples 1 to 3 and Comparative Example 1. Etching was performed for 100 seconds using an etchant composition having a temperature of about 30 ° C when etching. The etching rate according to time was obtained by visually measuring EPD (end point detection, metal etching timing). The profile profile of the etched Cu monolayer was examined using SEM (Hitachi, Model S4700), and the results are shown in Table 2 below.

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

Etching of the Cu/Mo-Ti double layer was performed using the etching liquid compositions of Examples 4 to 10 and Comparative Examples 2 to 4. Etching was performed for 100 seconds using an etchant composition having a temperature of about 30 ° C when etching. The etching rate according to time was obtained by visually measuring EPD (end point detection, metal etching timing). The profile profile of the etched Cu/Mo-Ti bilayer was examined using SEM (Hitachi, Model S4700) and the results are shown in Table 2 below.

<Evaluation criteria>

○: Excellent (CD skew) 1μm, cone angle: 40°~60°)

△: good (1μm<CD skew) 2μm, cone angle: 30°~70°)

×: Poor (metal layer loss and residue generation, taper angle: 80° or more)

Experimental Example 2: Evaluation of the number of sheets processed

A reference test (reference etching) was carried out using the etching liquid compositions of Examples 1 to 10 and Comparative Examples 1 to 4, and 4000 ppm of copper powder was added to the etching liquid for the reference test and completely dissolved. Thereafter, the reference test was etched again, 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%)

×: difference (the reduction rate of the etching rate is greater than 20%)

Claims (10)

An etchant composition comprising: a metal layer oxidizing agent; a compound having both an amino acid group and a polyethylene glycol group in a molecule; and water. The etching liquid composition according to claim 1, wherein the compound having both an amino acid group and a polyethylene glycol group in the molecule is represented by the following Chemical Formula 1: Wherein, in the formula, R ₁ and R ₂ are each independently hydrogen or a C1 to C8 linear or branched alkyl group, and R ₁ and R ₂ are bonded to each other to form a C4 to C10 cycloalkyl group, and R ₁ And R ₂ may form an amine group-containing C4 to C10 heterocyclic ring by combining with an amine group; R ₃ is hydrogen or a C1 to C8 linear or branched alkyl group; and n is a natural number of 1 to 20. The etching liquid composition according to claim 1, wherein the metal layer oxidizing agent is one or more selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, and hydrohalic acid. The etching liquid composition according to claim 1, wherein the first metal layer oxidizing agent is included in an amount of from 1% by weight to 40% by weight based on the total weight of the foregoing composition; and from 1% by weight to 40% by weight, the aforementioned amino acid is simultaneously contained in the molecule. a compound of a group and a polyethylene glycol group; and a remaining amount of water. The etching liquid composition according to claim 4, which further comprises one selected from the group consisting of 0.1% by weight to 5% by weight of a fluorine compound and 0.01% by weight to 10% by weight of a sulfur atom or a phosphorus atom-containing acid or Multiple species. The etching liquid composition according to claim 5, wherein the metal layer oxidizing agent contains 1% by weight to 25% by weight of hydrogen peroxide; and the acid containing a sulfur atom or a phosphorus atom is phosphoric acid. The etching solution composition according to claim 2, wherein in the above Chemical Formula 1, the linear or branched alkyl group of C1 to C8 is a methyl group, an ethyl group, a propyl group or a butyl group; and the aforementioned C4 to C10 cycloalkyl group; Is a C5 cycloalkyl or C6 cycloalkyl; and n is a natural number from 2 to 10. 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 8, wherein the plurality of layers are a copper-based metal layer/molybdenum 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 the substrate; b) a step of forming a gate insulator on the substrate including the gate; c) forming a semiconductor layer on the gate insulator a step of forming a source/drain on the aforementioned semiconductor layer; and e) a step of forming a pixel electrode connected to the aforementioned drain electrode; wherein the step a), d) or e) comprises forming a metal layer and Using the etching liquid composition according to any one of claims 1 to 7 before etching The step of forming a metal layer to form an electrode.