KR102204210B1 - 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; Compounds containing both an amino acid group and a polyethylene glycol group in the molecule; 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 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 Publication No. 10-2011-0031796 discloses an etchant comprising A) hydrogen peroxide (H ₂ O ₂ ) B) persulfate, C) 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 A) ammonium hydroxide, B) hydrogen peroxide, C) a fluorine-containing compound, D) a polyhydric alcohol and E) 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, excellent storage stability, in particular, an etchant composition of a metal film and a liquid crystal display using the same, which has excellent etch rate and ability to process a large amount of substrate 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; Compounds containing both an amino acid group and a polyethylene glycol group in the molecule; And it provides an etchant composition comprising water.

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) In a method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the 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. to provide.

The metal film etchant composition of the present invention includes a compound containing both an amino acid group and a polyethylene glycol group in the molecule, thereby increasing the etch rate and providing an effect of processing a large amount of substrates.

In addition, the etchant composition for a metal film including a copper-based film according to an embodiment of the present invention contains a low amount of hydrogen peroxide, thereby providing excellent work safety and an effect of economically disposing of the etchant, while providing an excellent etching rate. In addition, it provides a large amount of substrate processing capability and excellent storage stability.

In addition, the manufacturing method of an array substrate for a liquid crystal display device using the etchant composition of the present invention is to prepare an array substrate for a liquid crystal display device having excellent driving characteristics by forming an electrode having an excellent etching profile on an array substrate for a liquid crystal display device. Makes it possible.

The present invention,

Metal film oxidizer; Compounds containing both an amino acid group and a polyethylene glycol group in the molecule; And it relates to an etchant composition comprising water.

A compound containing both an amino acid group and a polyethylene glycol group in the molecule may be represented by the following formula:

[Formula 1]

In the above formula,

R ₁ and R ₂ are each independently hydrogen or a C1-C8 linear or branched alkyl group, and R ₁ and R ₂ may be bonded to each other to form a C4-C10 cycloalkyl, and R ₁ or R ₂ may be combined with an amine group to form a C4-C10 hetero ring including an amine group;

Each of R ₃ is independently hydrogen or a C1-C8 linear or branched alkyl group;

n is a natural number from 1 to 20.

The metal film oxidizing agent is not particularly limited, and may be typically at least one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, halogen acid, and halide salt.

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

The compound containing both an amino acid group and a polyethylene glycol group in the molecule has a structure in which an amino acid and polyethylene glycol are bonded. Accordingly, it has a feature of increasing the etching rate of the metal film and increasing the number of substrates processed. It also improves the storage stability of the etching solution.

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

In addition, it is more preferable that n in Formula 1 is a natural number of 2 to 10.

The etchant composition comprises 1 to 40% by weight of a metal film oxidizing agent, and 1 to 10% by weight of a compound containing an amino acid group and a polyethylene glycol group in the molecule, based on the total weight of the composition; And the remaining amount of water.

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

More preferably, the compound containing both an amino acid group and a polyethylene glycol group in the molecule is contained in an amount of 2 to 5% by weight. When the component is contained in an amount of less than 1% by weight, it is difficult to expect an increase in the etching rate and an increase in the number of substrates processed, and when it exceeds 10% by weight, it is difficult to expect an increase in the effect any more, rather, the viscosity of the etchant increases. This is not preferable because it causes a decrease in the etch rate.

The etchant composition of the present invention may be used regardless of the type 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 double film of a copper-based metal film/molybdenum-based metal film with a molybdenum-based metal film as a lower film and a copper-based metal film as an upper film, and a molybdenum-based metal film/copper-based metal film/molybdenum-based metal film, Alternatively, a multilayer of a triple layer or more in which a copper-based metal film and a molybdenum-based metal film are alternately stacked, such as a copper-based metal film/molybdenum-based metal film/copper-based metal film, is included.

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 film and titanium 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 a triple layer or more multiple layers in which the system metal layers 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 etchant composition of the present invention may further include at least one selected from the group consisting of a fluorinated compound, an acid containing a sulfur (S) atom or a phosphorus (P) atom.

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

The fluorinated compound may be 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 capable of dissociating into the fluorine ion or the polyatomic fluoride ion may be one or two or more selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, sodium bifluoride, and potassium bifluoride.

The acid containing the sulfur (S) atom or phosphorus (P) atom 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 acid satisfies the above range, the risk of excessive etching of the metal layer due to the acid and corrosion of the lower layer can be avoided, and the problem of lowering the etching rate of the metal layer due to the too low content of the acid does not occur. Function can be performed.

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 phosphonic acid may be used without limitation, and phosphoric acid may be preferably used. . The phosphoric acid provides hydrogen ions to the etching solution, thereby promoting the etching of copper of hydrogen peroxide. In addition, the solubility in water is increased by bonding with oxidized copper ions to form phosphate, thereby removing residues of the metal film after etching.

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

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

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

Hydrogen peroxide is used as the metal film oxidizing agent, and a fluorine-containing compound may be further included along with water and a compound containing an amino acid group and a polyethylene glycol group in the molecule at the same time.

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

In particular, the etchant composition may be preferably used for etching a copper-based metal film or a copper-based metal film/molybdenum metal film or a copper-based metal film/titanium-based metal film. However, the use of the composition is not limited to the film quality.

The hydrogen peroxide is a main component that oxidizes copper, molybdenum, and titanium. The hydrogen peroxide 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. If the above-described range is satisfied, a decrease in the etching rate of copper, molybdenum, and titanium is prevented, an appropriate amount of etching can be implemented, and an excellent etching profile can 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 a pattern and loss of a function as a metal wiring.

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

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

Step a), d) or e) comprises forming a metal film, and etching the metal film with the etching solution composition of the present invention to form an electrode. 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 1-10 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 Compounds containing both amino acid and polyethylene glycol groups in the molecule Ammonium fluoride Phosphoric acid Triethylene glycol Deionized water Example 1 nitric acid 10 Formula 2 5 Balance Example 2 Ammonium persulfate 10 Formula 2 5 Balance Example 3 Hydrogen peroxide 10 Formula 2 5 Balance Example 4 Hydrogen peroxide 10 Formula 2 5 One Balance Example 5 Hydrogen peroxide 10 Formula 2 5 One 0.1 Balance Example 6 Hydrogen peroxide 5 Formula 2 5 One 0.1 Balance Example 7 Hydrogen peroxide 5 Formula 3 5 One 0.1 Balance Example 8 Hydrogen peroxide 5 Formula 4 5 One 0.1 Balance Example 9 Hydrogen peroxide 5 Formula 5 5 One 0.1 Balance Example 10 Hydrogen peroxide 5 Formula 6 5 One 0.1 Balance Comparative Example 1 Hydrogen peroxide 10 Glycine 5 Balance Comparative Example 2 Hydrogen peroxide 10 5 One Balance Comparative Example 3 Hydrogen peroxide 10 Glycine 5 One 0.1 Balance Comparative Example 4 Hydrogen peroxide 10 One 0.1 5 Balance

(Unit: wt%)

week)

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

Test example One: Etchant Composition of Etching characteristics evaluation

(One) Cu Single curtain Etching Speed evaluation

Etching of a single Cu film was performed using the etchant compositions of Examples 1 to 3 and Comparative Example 1. During the etching process, the temperature of the etchant composition was set to about 30°C and etching was performed for 100 seconds. With the naked eye, EPD (End Point Detection, metal etching time) was measured to obtain an etching rage over time. The profile cross-section of the etched Cu single layer was examined using SEM (Hitachi, model name S-4700), and the results are shown in Table 2 below.

(2) Cu / Mo - Ti Double membrane Etching Speed evaluation

The Cu/Mo-Ti double layer was etched using the etchant compositions of Examples 4 to 10 and Comparative Examples 2 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. With the naked eye, EPD (End Point Detection, metal etching time) was measured to obtain an etching rage over time. The profile cross-section of the etched Cu/Mo-Ti double layer was examined using SEM (Hitachi's product, model name S-4700), and the results are shown in Table 2 below.

<Evaluation criteria>

○: Excellent (CD Skew ≤ 1㎛, taper angle: 40-60°)

△: Good (1㎛ <CD Skew ≤ 2㎛, taper angle: 30-70°)

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

Test example 2. Evaluation of the number of processed purchases

A reference etch test was performed with the etchant compositions of Examples 1 to 10 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 rate of decrease of the etching rate was evaluated.

<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 speed (Å/sec) Number of processing Example 1 167 ○ Example 2 171 ○ Example 3 137 ○ Example 4 146 ○ Example 5 152 ○ Example 6 149 ○ Example 7 153 ○ Example 8 167 ○ Example 9 178 ○ Example 10 168 ○ Comparative Example 1 156 △ Comparative Example 2 57 × Comparative Example 3 161 △ Comparative Example 4 37 △

Claims (10)

1 to 40% by weight of a metal film oxidizer based on the total weight of the etchant composition; 1 to 10% by weight of a compound containing an amino acid group and a polyethylene glycol group simultaneously in a molecule represented by the following formula (1); And an etchant composition comprising the remaining amount of water:
[Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently hydrogen or a C1-C8 linear or branched alkyl group, and R ₁ and R ₂ may be bonded to each other to form a C4-C10 cycloalkyl, and R ₁ or R ₂ may be combined with an amine group to form a C4-C10 hetero ring including an amine group;
Each of R ₃ is independently hydrogen or a C1-C8 linear or branched alkyl group;
n is a natural number from 1 to 20.
delete The method according to claim 1,
The metal layer oxidizing agent is at least one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, and halogen acid. delete The method according to claim 1,
An etching solution composition, characterized in that the fluorinated compound further comprises at least one selected from the group consisting of 0.1 to 5% by weight and 0.01 to 10% by weight of an acid containing sulfur (S) atoms or phosphorus (P) atoms. The method of claim 5,
Hydrogen peroxide is contained in an amount of 1 to 25% by weight as the metal film oxidizing agent; Etching liquid composition, characterized in that the acid containing sulfur (S) atom or phosphorus (P) atom is phosphoric acid. The method according to claim 1,
In R ₁ to R ₃ of Formula 1, the C1 to C8 linear or branched alkyl group is a methyl group, an ethyl group, a propyl group, or a butyl group, and the C4 to C10 cycloalkyl is a C5 or C6 cycloalkyl;
The etchant composition, characterized in that n is a natural number of 2 to 10. The method according to claim 1,
The etchant composition is 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 method of claim 8,
The etchant composition, wherein the multilayer film is a copper-based metal film/molybdenum metal film, or a copper-based metal film/titanium 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) In a method of manufacturing an array substrate for a liquid crystal display device comprising the step of forming a pixel electrode connected to the drain electrode,
The liquid crystal, characterized in that the step a), d) or e) comprises forming an electrode by forming a metal film, and etching the metal film with the etchant composition of any one of claims 1, 3, 5 to 7 A method of manufacturing an array substrate for a display device.