KR102204228B1 - 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 is a metal film oxidizing agent; Fluorine-containing compounds; Nitrogen atom-containing compounds; Phosphoric acid; Polyethylene glycol; And an etchant composition containing the remaining amount of water,
The number of mmoles of repeating units of polyethylene glycol per 1 g of the etching solution composition is the value of ethylene oxide,
It provides an etchant composition, characterized in that the ethylene oxide value of the etchant composition is 0.4 to 2, and a method of manufacturing an array substrate for a liquid crystal display device, characterized in that 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, furthermore, copper or copper alloy, to reduce wiring resistance and increase adhesion to silicon insulating film as the screen becomes 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. It can contribute to a large screen. Therefore, 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 for the etching composition as described above, an etching solution based on hydrogen peroxide and an 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, and has excellent work stability, excellent etching speed, and processing capacity of a large amount of substrates, and among them, an etchant for a metal film exhibiting optimum etching characteristics with excellent etching speed and number of processed sheets. An object of the present invention is to provide a composition and a method of manufacturing an array substrate for a liquid crystal display device using the composition.

To achieve the above object,

The present invention is a metal film oxidizing agent; Fluorine-containing compounds; Nitrogen atom-containing compounds; Phosphoric acid; Polyethylene glycol of the following formula (1); And an etchant composition containing the remaining amount of water,

The number of mmoles of repeating units of polyethylene glycol represented by the following formula 1 for 1 g of the etching solution composition is the value of ethylene oxide,

It provides an etchant composition, characterized in that the ethylene oxide value of the etchant composition is 0.4 to 2.

[Formula 1]

N is an integer of 2 to 100,

R ₁ and R ₂ are each independently hydrogen, an aliphatic hydrocarbon having 1 to 4 carbon atoms, or phenyl.

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 can improve the number of processed etchant compositions by adjusting the number of repeating units of polyethylene glycol.

In addition, the metal film etchant composition of the present invention provides an excellent etching rate.

In addition, the etchant composition for a metal film comprising a copper-based film according to an embodiment of the present invention contains a low content of hydrogen peroxide as a metal oxidizing agent, thereby providing excellent work safety, cost competitiveness, and an effect of economically disposing of the etchant. Has features.

In addition, the method of manufacturing 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.

Hereinafter, the present invention will be described in more detail.

The present invention is a metal film oxidizing agent; Fluorine-containing compounds; Nitrogen atom-containing compounds; Phosphoric acid; Polyethylene glycol of the following formula (1); And an etchant composition containing the remaining amount of water,

The number of mmoles of repeating units of polyethylene glycol represented by the following formula 1 for 1 g of the etchant composition is the value of ethylene oxide,

It relates to an etchant composition, characterized in that the ethylene oxide value of the etchant composition is 0.4 to 2.

[Formula 1]

N is an integer of 2 to 100,

R ₁ and R ₂ are each independently hydrogen, an aliphatic hydrocarbon having 1 to 4 carbon atoms, or phenyl.

Further, it is more preferable that R ₁ and R ₂ are each independently hydrogen or methyl.

In the present invention, by controlling the number of repeating units of the polyethylene glycol of Formula 1, an etchant composition having an ethylene oxide value of 0.4 to 2 can be provided, and accordingly, the etching rate and the number of processed sheets are improved to show optimal etching properties. A metal film etchant composition may be provided.

In the present invention, the value of ethylene glycol is 0.4 to 2, more preferably 0.8 to 1.5. When the value of the ethylene glycol is less than 0.4, the effect of improving the number of processed sheets is insufficient, and when it exceeds 2, there is a problem in that the visual speed decreases due to an increase in viscosity.

The metal film oxidizing agent is not particularly limited as a main component that oxidizes the metal of the metal film, and representatively may be at least one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, halogen acid and halide. have.

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 metal film etchant composition, based on the total weight of the composition, metal film oxidizing agent 1 to 40% by weight; 0.1 to 5% by weight of a fluorinated compound; 1 to 10% by weight of a nitrogen-containing compound; 0.01 to 10% by weight of phosphoric acid; The weight percent of the polyethylene glycol of Formula 1 having an ethylene oxide value of 0.4 to 2; 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. If it is included in the above range, the etch rate of the metal layer may be appropriately adjusted.

The polyethylene glycol of Formula 1 of the present invention is an addition polymer of ethylene oxide, and the repeating unit is ethylene oxide. The polyethylene glycol of Formula 1 is included as a weight% having a value of 0.4 to 2, and preferably 0.8 to 1.5, of the polyethylene glycol of Formula 1 based on the total weight of the composition. Included. Accordingly, by controlling the number of repeating units of the polyethylene glycol of Formula 1, the number of processed sheets is improved, and an etchant composition in which the etching rate is not decreased can be provided.

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 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 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 nitrogen atom-containing compound contained in the etchant composition of the present invention serves to improve the etch rate and the number of sheets treated. As the nitrogen atom-containing compound, those known in the art may be used without limitation, and representatively, a compound containing an amino group and a carboxylic acid group in a molecule may be used,

Compounds containing an amino group and a carboxylic acid group in the molecule include an alpha amino acid containing one carbon atom between the carboxylic acid and the amino group, and representatively monovalent amino acids such as glycine, glutamic acid, glutamine, isoleucine proline, tyrosine, arginine, etc. And polyhydric amino acids such as iminodiacetic acid, nitrilodriacetic acid, and ethylene glycol tetraacetic acid. The nitrogen atom-containing compounds may be used alone or in combination of two or more.

The nitrogen atom-containing compound may be included 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 nitrogen atom-containing compound is included in the above-described range, the etching rate of the etching solution and the number of processed sheets may be improved.

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 bonding with oxidized copper ions to form phosphate, thereby removing residues of the metal film after etching.

The phosphoric acid 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 phosphoric acid satisfies the above-described range, it is possible to avoid the risk of excessive etching of the metal layer due to the phosphoric acid and corrosion of the lower layer, and there is no problem that the etching rate of the copper metal layer is lowered because the phosphoric acid content is too low. It can perform its original function.

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.

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.

The etchant composition of the present invention does not specifically limit the type of the metal film to be etched, but may be 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/molybdenum-based metal film having a molybdenum-based metal film as a lower film and a copper-based metal film as an upper film; Copper-based metal film/molybdenum-titanium alloy film double-layer and molybdenum-based metal film/copper-based metal film/molybdenum-based metal film, or copper-based metal film/molybdenum-based metal film/copper Like a metal film, a copper-based metal film and a molybdenum-based metal film are alternately stacked, including a triple or more multilayer.

In addition, the multilayer film is, for example, a titanium-based metal film as a lower film and a titanium-based metal film as an upper film, a double film of a titanium-based metal film/copper-based metal film, a titanium-based metal film as a lower film, and a copper-based metal film as an upper film. A double film of a copper-based metal film/titanium-based metal film; A copper-based metal film like a copper-based metal film/molybdenum-titanium alloy film double-layer 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 And a multilayer of a triple layer or more in which the and titanium-based 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 is a specific example,

Hydrogen peroxide is used as the metal film oxidizing agent, and a fluorine-containing compound; Nitrogen-containing compounds; Phosphoric acid; Polyethylene glycol of Formula 1; And the remaining amount of water.

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

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 more than 1 and 10% by weight or less, and more preferably more than 1 and 5% by weight or less 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 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 liquid crystal display array substrate 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.

< Etchant Composition Preparation>

Example 1 to 6 and Comparative example 1 to 6.

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

(Unit: wt%) division Hydrogen peroxide Ammonium fluoride Glycine Phosphoric acid Polyethylene glycol Deionized water Ethylene glycol level Example 1 5 One 3 0.1 Formula 2 5 Balance 0.94 Example 2 5 One 3 0.1 Formula 3 5 Balance 1.00 Example 3 5 One 3 0.1 Formula 4 5 Balance 0.91 Example 4 5 One 3 0.1 Formula 5 5 Balance 0.90 Example 5 5 One 3 0.1 Formula 3 2 Balance 0.40 Example 6 5 One 3 0.1 Formula 3 10 Balance 2.00 Comparative Example 1 5 One 3 0.1 Formula 3 One Balance 0.2 Comparative Example 2 5 One 3 0.1 Formula 3 15 Balance 3.00 Comparative Example 3 5 One 3 0.1 Formula 6 4 Balance 0.34 Comparative Example 4 5 One 3 0.1 Formula 7 2 Balance 0.25 Comparative Example 5 5 One 3 0.1 Formula 8 One Balance 0.11 Comparative Example 6 5 One 3 0.1 - - Balance 0

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

Experimental example One. Etchant Composition of Cu / Mo - Ti Double membrane Etching characteristics evaluation

The Cu/Mo-Ti double layer was etched using the etchant compositions of Examples 1 to 6 and Comparative Examples 1 to 6. 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.

Experimental example 2. Evaluation of the number of processed purchases

A reference etch test was performed with the etchant compositions of Examples 1 to 6 and Comparative Examples 1 to 6, 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 characteristics Number of processing Etching speed (Å/sec) Example 1 123 ○ Example 2 127 ○ Example 3 128 ○ Example 4 119 ○ Example 5 131 ○ Example 6 100 ○ Comparative Example 1 128 × Comparative Example 2 88 ○ Comparative Example 3 123 △ Comparative Example 4 121 △ Comparative Example 5 124 × Comparative Example 6 130 ×

Claims (9)

1 to 40% by weight of a metal film oxidizer based on the total weight of the composition; 0.1 to 5% by weight of a fluorinated compound; 1 to 10% by weight of a nitrogen atom-containing compound; 0.01 to 10% by weight of phosphoric acid; The weight percent of the polyethylene glycol of the following formula (1) to make the ethylene oxide level of 0.4 to 2; And an etchant composition containing the remaining amount of water,
The number of mmoles of repeating units of polyethylene glycol represented by the following formula 1 for 1 g of the etchant composition is the value of ethylene oxide,
Etching liquid composition, characterized in that the ethylene oxide value of the etchant composition is 0.4 to 2.
[Formula 1]

N is an integer of 2 to 100,
R ₁ and R ₂ are each independently hydrogen, an aliphatic hydrocarbon having 1 to 4 carbon atoms, or phenyl. The etchant composition according to claim 1, wherein R ₁ and R ₂ are each independently hydrogen or a methyl group. The etchant composition according to claim 1, wherein the metal layer oxidizing agent is at least one selected from the group consisting of hydrogen peroxide, peracetic acid, metal oxide, nitric acid, persulfate, halogen acid and halide. delete The etching solution composition of claim 1, wherein hydrogen peroxide is included as the metal layer oxidizing agent. The etchant composition according to claim 5, wherein the hydrogen peroxide is contained in an amount of 1 to 25% by weight based on the total weight of the composition, and the nitrogen atom-containing compound is an amino acid. The etchant composition of claim 1, wherein 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 etchant composition according to claim 7, wherein the multilayer 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 alloy 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 to 3 and 5 to 8. A method of manufacturing an array substrate for a display device.