KR102209687B1 - Etching solution composition for metal layer and manufacturing method of an array substrate for liquid crystal display using the same - Google Patents

Abstract

The present invention provides a metal film oxidizing agent; Fluorine-containing compounds; Thioacid; And an etchant composition comprising water, and a method of manufacturing an array substrate for a liquid crystal display, comprising using the composition.

Description

Etching liquid composition of metal film and manufacturing method of array substrate for liquid crystal display using the same {ETCHING SOLUTION COMPOSITION FOR METAL LAYER AND MANUFACTURING METHOD OF AN ARRAY SUBSTRATE FOR LIQUID CRYSTAL DISPLAY USING THE SAME}

The present invention relates to an etchant composition for a metal film and a method of manufacturing an array substrate for a liquid crystal display using the same.

In the case of flat panel displays such as LCD, PDP and OLED, especially TFT-LCD, a single film made of copper or copper alloy, and furthermore, copper or copper is used to reduce wiring resistance and increase adhesion with silicon insulating film while becoming larger. The adoption of a multilayer of two or more layers of alloys/other metals, alloys of other metals, or metal oxides has been widely studied. For example, a copper/molybdenum film, a copper/titanium film, or a copper/molybdenum-titanium film can form a source/drain wire constituting a gate wire and a data line of a TFT-LCD, thereby contributing to the enlargement of the display. I can. Accordingly, there is a need to develop a composition having excellent etching properties capable of etching a metal film including the copper-based film as described above.

As the above-described etching composition, an etching solution based on hydrogen peroxide and amino acid, an etching solution based on hydrogen peroxide and phosphoric acid, and an etching solution based on hydrogen peroxide and polyethylene glycol are known.

For example, Korean Patent Laid-Open No. 10-2011-0031796 discloses an etchant containing hydrogen peroxide (H ₂ O ₂ ), persulfate, a water-soluble compound having an amine group and a carboxyl group, and water.

Republic of Korea Patent Publication No. 10-2012-0044630 discloses a copper-containing metal film etching solution containing hydrogen peroxide, phosphoric acid, a cyclic amine compound, sulfate, boronic acid and water.

Republic of Korea Patent Publication No. 10-2012-0081764 discloses an etching solution containing ammonium hydroxide, hydrogen peroxide, a fluorine-containing compound, a polyhydric alcohol, and water.

However, the above etchants do not sufficiently satisfy the conditions required in this field in terms of CD loss, taper, pattern straightness, metal residue, storage stability, and number of processed sheets for a metal film including a copper-based film. have.

Republic of Korea Patent Publication No. 10-2011-0031796 Republic of Korea Patent Publication No. 10-2012-0044630 Republic of Korea Patent Publication No. 10-2012-0081764

The present invention is to solve the problems of the prior art as described above, has excellent work safety, has excellent storage stability and a large amount of substrate processing capability, and has particularly excellent etching rate, an etchant composition for a metal film and a liquid crystal display using the same It is an object of the present invention to provide a method of manufacturing an array substrate for an apparatus.

The present invention,

Metal film oxidizer (A); Fluorinated compound (B); Thioacid (C); And it provides an etchant composition comprising the water (D).

In the present invention, the thioacid is a compound containing unoxidized sulfur (S) and a carboxylic acid group in the molecule, and S is preferably a compound represented by the following formulas 1 to 4 bonding with the alpha carbon of the carboxylic acid group. .

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4,

R ₁ to R ₄ may be the same or different, and may be an organic group capable of being bonded to each other to form a ring structure,

Each is hydrogen, C1-C20 linear, branched or cyclic alkyl, alkenyl, alkynyl, aryl or arylalkyl;

The alkyl, alkenyl, alkynyl, aryl or aryl alkyl is

Hydroxyl, carbonyl, carboxyl, epoxy, ether, amino, amide, thio, silyl, sulfo, halo, may include one or more of the group consisting of -O-, -N-, one or more, but not limited thereto. May contain functional groups,

X in Formula 3 may be one selected from the group consisting of -C-, -N-, -P-, and the like.

In addition, the present invention

a) forming a gate electrode on the substrate;

b) forming a gate insulating layer on the substrate including the gate electrode;

c) forming a semiconductor layer on the gate insulating layer;

d) forming source/drain electrodes on the semiconductor layer; And

e) A method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the source/drain electrode,

Step a), d), or e) comprises forming a metal film, and etching the metal film with the etchant composition of the present invention to form an electrode. Provides.

The metal film etchant composition of the present invention contains a low content of the metal film oxidizing agent, thereby providing excellent work safety and an effect of economically disposing of the etchant.

In addition, it has the ability to process a large amount of substrates, and has the feature of providing particularly good etching rates.

In addition, the method of manufacturing an array substrate for a liquid crystal display using the etchant composition of the present invention is an array for a liquid crystal display device having excellent driving characteristics by forming a source/drain electrode having an excellent etching profile on the array substrate for a liquid crystal display device. It enables the manufacture of the substrate.

The present invention,

Metal film oxidizer (A); Fluorinated compound (B); Thioacid (C); And it relates to an etchant composition comprising water (D).

The present inventors have made diligent efforts to treat waste of etchant, process safety problem, secure price competitiveness, improve the number of treatment sheets, and improve the etching rate.The present invention is used as an etchant composition including a thioacid and the like by lowering the concentration of the metal film oxidizer. Finished.

Hereinafter, each component constituting the etchant composition of the present invention will be described. However, the present invention is not limited to these components.

(A) Metal film Oxidant

In the present invention, the metal film oxidizing agent is a main component that oxidizes the metal of the metal film, and is not particularly limited, and is typically at least one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, halogen acid, halide, etc. It may be, and more preferably hydrogen peroxide.

The metal oxide refers to an oxidized metal, for example, Fe ^{3 +} , Cu ^{2 +} and the like, and the metal oxide also includes a compound that dissociates into the Fe ^{3 +} , Cu ^{2 +} and the like in a solution state. The persulfate includes ammonium persulfate, persulfate alkali metal salt, oxone, and the like, and the halide salt includes chlorate, perchlorate, bromate, perbromate, and the like.

In the present invention, the metal film oxidizer is a main component that oxidizes copper, molybdenum or titanium. The metal film oxidizing agent is preferably contained in an amount of 1 to 25% by weight, preferably 1 to 10% by weight, more preferably 1 to 5% by weight, based on the total weight of the composition. When the above-described range is satisfied, a decrease in etching rates of copper, molybdenum, and titanium is prevented, an appropriate amount of etching may be implemented, and an excellent etching profile may be obtained. However, outside the above-described range, the layer to be etched may not be etched, or over-etching may occur, resulting in loss of patterns and loss of functions as a metal wiring.

The content of the metal layer oxidizing agent may be appropriately adjusted according to the type and characteristics of the oxidizing agent.

(B) Fluorine-containing compound

The fluorine-containing compound contained in the etchant composition of the present invention serves to remove etching residues and serves to etch the titanium-based metal film.

The fluorinated compound is preferably contained in an amount of 0.1 to 5% by weight, more preferably 0.1 to 2% by weight, based on the total weight of the composition. If the above-described range is satisfied, it is preferable because the etching residue is prevented and the etching of the glass substrate or the lower silicon film is not caused. However, outside the above-described range, stains may occur in the substrate due to non-uniform etching characteristics, the lower layer may be damaged due to an excessive etching rate, and it may be difficult to control the etching rate during processing.

The fluorine-containing compound is preferably a compound capable of dissociating into fluorine ions or polyatomic fluorine ions. The compound that can be dissociated into the fluorine ion or polyatomic fluoride ion may be one or two or more selected from the group consisting of hydrofluoric acid, ammonium fluoride, sodium fluoride, potassium fluoride, sodium bifluoride, and potassium bifluoride, and further It is preferably ammonium fluoride and/or hydrofluoric acid.

(C) Thioacid

The thioacid contained in the etchant composition of the present invention serves to improve the etching rate in the etchant composition.

The thioacid is preferably contained in an amount of 0.1 to 10% by weight, more preferably 1 to 5% by weight, based on the total weight of the composition. When the thioacid is contained in an amount of less than 0.1% by weight, it is difficult to expect an improvement in the number of processed sheets and an increase in the etching rate, and when it exceeds 10% by weight, it is difficult to expect an increase in the effect any more. It is not preferable because the etch rate is lowered. That is, when the content of the thioacid satisfies the above-described range, the risk of excessive etching of the metal layer and corrosion of other lower layers may be avoided, and a decrease in the etching rate may be prevented.

In the present invention, a thioacid is a compound containing unoxidized S and a carboxylic acid group in the molecule,

The S is preferably at least one selected from the group consisting of the following formulas 1 to 4 bonded to the alpha carbon of the carboxylic acid group.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4,

R ₁ to R ₄ may be the same or different, and may be an organic group capable of being bonded to each other to form a ring structure,

Each is hydrogen, C1-C20 linear, branched or cyclic alkyl, alkenyl, alkynyl, aryl or arylalkyl;

The alkyl, alkenyl, alkynyl, aryl or aryl alkyl is

Hydroxyl, carbonyl, carboxyl, epoxy, ether, amino, amide, thio, silyl, sulfo, halo, may include one or more of the group consisting of -O-, -N-, one or more, but not limited thereto. May contain functional groups,

X in Formula 3 may be one selected from the group consisting of -C-, -N-, -P-, and the like.

As the general formula 1, more preferably the following Chemical Formulas 5 to 8.

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

As the general formula 2, more preferably, the following Chemical Formulas 9 to 20 may be used.

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

As Formula 3, more preferably, the following Formulas 21 to 24 may be mentioned.

[Formula 21]

[Formula 22]

[Formula 23]

[Formula 24]

As Formula 4, more preferably, the following Formulas 25 to 26 may be mentioned.

[Formula 25]

[Formula 26]

(D) water

The water contained in the etchant composition of the present invention is not particularly limited, but preferably means deionized water, and more preferably, water having a specific resistance of 18 MΩ/cm or more is used as deionized water for semiconductor processing.

The content of water may be included as a balance based on 100% by weight of the total composition.

The etchant composition of the present invention may further include one or more selected from the group consisting of acids, glycols, etc. containing sulfur (S) atoms or phosphorus (P) atoms.

The acid containing sulfur (S) atoms or phosphorus (P) atoms contained in the etchant composition of the present invention may be included in an amount of 0.01 to 10% by weight, more preferably 0.01 to 1% by weight, based on the total weight of the composition. . When the content of the acid satisfies the above-described range, the risk of excessive etching of the metal layer due to the acid and corrosion of other lower layers can be avoided, and the problem of lowering the etching rate of the metal layer due to the too low acid content does not occur. Therefore, it can perform its original function.

As the acid containing the sulfur (S) atom or phosphorus (P) atom, components known in the art such as sulfuric acid, sulfonic acid, phosphoric acid, and phosphoric acid may be used without limitation, and phosphoric acid may be preferably used. . The phosphoric acid provides hydrogen ions to the etchant to promote copper etching of the metal layer oxidizer. In addition, the solubility in water is increased by combining with oxidized copper ions to form phosphate, thereby removing residues of the copper metal film after etching.

The glycols contained in the etchant composition of the present invention cover the metal ions dissolved in the etchant after etching the metal film, thereby inhibiting the activity of the metal ions and suppressing the decomposition reaction of the metal film oxidizer. If the activity of the metal ions is lowered in this way, the process can be stably performed while the etchant is used, and the number of substrates processed is increased.

The content of the glycols is 0.1 to 10% by weight, preferably 1 to 5% by weight, based on the total weight of the composition. When the glycol content is contained in an amount of less than 0.1% by weight, a problem of deteriorating etching uniformity may occur, and when it exceeds 10% by weight, there may be a disadvantage in that a lot of bubbles are generated.

As the glycols, components known in this field may be used without limitation, and in particular, polyethylene glycol may be preferably used, and triethylene glycol may be used as an example.

The polyethylene glycol is an addition polymer of ethylene oxide, and may be either a hydroxy or an ether group, but at least one is preferably a hydroxy group. Further, in order to suppress excessive increase in the viscosity of the solution, the molecular weight is more preferably 1000 or less.

Triethylene glycol may be mentioned as an example of the polyethylene glycol.

The etchant composition of the present invention is a specific example,

Hydrogen peroxide is used as the metal film oxidizing agent, along with a fluorine-containing compound, a thioacid, and water, 0.01 to 10% by weight of an acid containing a sulfur (S) atom or a phosphorus (P) atom with respect to the total weight of the composition, and 0.1 to 0.1 to glycols It may be to further include one or more selected from the group consisting of 10% by weight.

The etchant composition of the present invention may further include at least one of an etch control agent, a surfactant, a metal ion sequestering agent, a corrosion inhibitor, and a pH adjuster in addition to the above-mentioned components.

It is preferable that the components constituting the etchant composition of the present invention have a purity for semiconductor processing.

The etchant composition of the present invention may be used regardless of the quality of the etching film, but may be more preferably used for etching a copper-based metal film, a molybdenum-based metal film, a titanium-based metal film, or a multilayer film made of them.

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

The multilayer film may include, for example, a double layer of a molybdenum-based metal film/copper-based metal film having a copper-based metal film as a lower film and a molybdenum-based metal film as an upper film; A copper-based metal film with a molybdenum-based metal film as a lower film and a copper-based metal film as an upper film/double film of a molybdenum-based metal film, a double film of a copper-based metal film/molybdenum-titanium-based metal film, and a molybdenum-based metal film Metal film/copper-based metal film/molybdenum-based metal film, or copper-based metal film/molybdenum-based metal film/copper-based metal film. Includes multiple membranes.

In addition, the multilayer film is, for example, a copper-based metal film as a lower film, a titanium-based metal film as an upper film, a titanium-based metal film/copper-based metal film as a double film, a titanium-based metal film as a lower film, and a copper-based metal film as an upper film. Copper-based metal and titanium-based like a double-layer of a copper-based metal film/titanium-based metal film, and a titanium-based metal film/copper-based metal film/titanium-based metal film or a copper-based metal film/titanium-based metal film/copper-based metal film It includes three or more multilayers in which metal films are alternately stacked.

In the multilayer film, the interlayer bonding structure may be determined in consideration of a material constituting a film disposed above or below the multilayer film, or adhesion with the films.

In the above, the copper, molybdenum, or titanium alloy film refers to a metal film made of an alloy using copper, molybdenum, or titanium as a main component according to the characteristics of the film. For example, the molybdenum alloy film contains molybdenum as a main component, and at least one selected from titanium (Ti), tantalum (Ta), chromium (Cr), nickel (Ni), neodymium (Nd), and indium (In) It means a film made of an alloy formed including.

The etching solution composition of the present invention is particularly suitable for etching a copper-based metal film, a copper-based metal film/molybdenum-based metal film, a copper-based metal film/titanium-based metal film, or a copper-based metal film/molybdenum-titanium-based metal film. It can be preferably used. However, the use of the composition is not limited to the double layer.

The present invention also,

a) forming a gate electrode on the substrate;

b) forming a gate insulating layer on the substrate including the gate electrode;

c) forming a semiconductor layer on the gate insulating layer;

d) forming source/drain electrodes on the semiconductor layer; And

e) A method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the source/drain electrode,

Step a), d), or e) comprises forming a metal film, and etching the metal film with the etchant composition of the present invention to form an electrode. It is about.

Since the array substrate for a liquid crystal display manufactured by the above method includes an electrode having an excellent etching profile, it has excellent driving characteristics.

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

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are for explaining the present invention more specifically, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

Example 1 to 9 and Comparative example 1-4: Etchant Preparation of the composition

An etchant composition was prepared by mixing the components shown in Table 1 below in the corresponding amount.

division Metal film oxidizer Ammonium fluoride Thioacid Triethylene
Glycol Phosphoric acid Deionized water Example 1 nitric acid 10 2 Formula 5 3 - - Balance Example 2 ammonium
Persulfate 10 2 Formula 5 3 - - Balance Example 3 Hydrogen peroxide 10 2 Formula 5 3 - - Balance Example 4 Hydrogen peroxide 5 2 Formula 5 3 5 - Balance Example 5 Hydrogen peroxide 5 2 Formula 5 3 5 0.1 Balance Example 6 Hydrogen peroxide 5 2 Formula 8 3 5 0.1 Balance Example 7 Hydrogen peroxide 5 2 Formula 9 3 5 0.1 Balance Example 8 Hydrogen peroxide 5 2 Formula 22 3 5 0.1 Balance Example 9 Hydrogen peroxide 5 2 Formula 25 3 5 0.1 Balance Comparative Example 1 Hydrogen peroxide 5 2 - - - - Balance Comparative Example 2 Hydrogen peroxide 5 2 - - - 0.1 Balance Comparative Example 3 Hydrogen peroxide 5 2 - - 5 - Balance Comparative Example 4 Hydrogen peroxide 5 2 - - 5 0.1 Balance

(Unit: wt%)

Test example One: Etchant Composition of Etching characteristics evaluation

(One) Cu / Mo - Ti Double membrane Etching

The Cu/Mo-Ti double layer was etched using the etchant compositions of Examples 1 to 9 and Comparative Examples 1 to 4. During the etching process, the temperature of the etchant composition was set to about 30°C and etching was performed for 100 seconds. By measuring EPD (End Point Detection, metal etching time point) with the naked eye, an etching rate over time was obtained, and the results are shown in Table 2 below.

Test example 2: Evaluation of the number of processed sheets

A reference etch test was performed with the etchant compositions of Examples 1 to 9 and Comparative Examples 1 to 4, and 4,000 ppm of copper powder was added to the reference test etchant to completely dissolve. Thereafter, etching was performed again, a reference etching test was performed, and the result was evaluated as a decrease rate of the etching rate, and the results are shown in Table 2 below.

<Evaluation criteria>

○: Excellent (less than 10% etch rate decrease)

△: Good (Etch rate decrease rate 10% ~ 20%)

×: Defective (Etch rate reduction rate exceeds 20%)

division Etching characteristics
Number of processing Etching speed (Å/sec) Example 1 171 △ Example 2 182 △ Example 3 157 △ Example 4 159 ○ Example 5 178 ○ Example 6 182 ○ Example 7 180 ○ Example 8 175 ○ Example 9 188 ○ Comparative Example 1 35 × Comparative Example 2 58 × Comparative Example 3 41 △ Comparative Example 4 62 △

Claims (9)

Based on the total weight of the composition,
1 to 25% by weight of metal film oxidizer;
0.1 to 5% by weight of a fluorinated compound;
0.1 to 10% by weight of thioacid; And
An etchant composition comprising the remaining amount of water,
The thioacid is at least one selected from the group consisting of the following formulas 1 to 4,
The etchant composition is characterized in that used for etching a copper-based metal film or a multilayer film including a copper-based metal film.
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4,
R ₁ to R ₄ may be the same or different, and may be an organic group capable of being bonded to each other to form a ring structure,
Each is hydrogen, C1 to C20 linear, branched or cyclic alkyl, alkenyl, alkynyl, aryl or arylalkyl;
The alkyl, alkenyl, alkynyl, aryl or aryl alkyl is
Hydroxyl, carbonyl, carboxyl, epoxy, ether, amino, amide, thio, silyl, sulfo, halo, may contain one or more of the group consisting of -O-, -N-,
X in Formula 3 is one selected from the group consisting of -C-, -N-, and -P-. delete The method according to claim 1,
The metal film oxidizing agent is an etchant composition, characterized in that at least one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, halogen acid and halide. delete The method according to claim 1,
Hydrogen peroxide is used as the metal film oxidizing agent, and at least one selected from the group consisting of 0.01 to 10% by weight of an acid containing sulfur (S) atom or phosphorus (P) atom, and 0.1 to 10% by weight of glycols is further included. Etching liquid composition, characterized in that. The method of claim 5,
An etchant composition, wherein the acid containing a sulfur (S) atom or a phosphorus (P) atom is phosphoric acid, and the glycols are polyethylene glycol. delete The method according to claim 1,
An etchant composition, characterized in that the multilayer film including the copper-based metal film is a copper-based metal film/molybdenum metal film, a copper-based metal film/titanium-based metal film, or a copper-based metal film/molybdenum-titanium-based metal film . a) forming a gate electrode on the substrate;
b) forming a gate insulating layer on the substrate including the gate electrode;
c) forming a semiconductor layer on the gate insulating layer;
d) forming source/drain electrodes on the semiconductor layer; And
e) A method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the source/drain electrode,
The step a), d) or e) includes forming a metal film, and etching the metal film with the etchant composition of any one of claims 1, 3, 5, 6, and 8 to form an electrode. Method of manufacturing an array substrate for a liquid crystal display device.