KR20160115715A - Etchant composition and manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

The present invention relates to an etchant composition, and a manufacturing method of an array substrate for a liquid crystal display. The etchant composition of the present invention is able to reduce a total processing time and manufacturing costs by wet etching an amorphous silicon thin film (n+a-Si:H) or a metal-oxide layer, a multilayer including one or more layer selected from a copper layer or a copper alloy layer, and one or more layer selected from a group comprised of a titanium layer and a titanium alloy layer in a lump.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching liquid composition for a liquid crystal display device,

The present invention relates to an etching liquid composition and a method of manufacturing an array substrate for a liquid crystal display.

And is a thin film transistor (TFT) which is a representative example of an electronic circuit for driving a semiconductor device and a flat panel display device. The manufacturing process of a TFT is generally composed of forming a metal film as a gate and a data wiring material on a substrate, forming a photoresist in a selective region of the metal film, and etching the upper metal film using the photoresist as a mask.

As a gate and a data wiring material, a copper single layer or a copper alloy layer containing copper having good electrical conductivity and low resistance and a metal oxide layer having excellent interfacial adhesion between these layers are used. In recent years, a film containing indium oxide, zinc oxide, or a mixture thereof together with gallium oxide has been used as a metal oxide film in order to improve the performance of a TFT.

Korean Patent Publication No. 2012-0138290 discloses a composition comprising a persulfate, a fluorine compound, an inorganic acid, a cyclic amine compound, a sulfonic acid, at least one of an organic acid and an organic salt, and a residual amount of water as an etching solution for etching a copper / . However, if the copper / titanium film is etched with the etching solution, the etching rate is high and the aging property is improved while the gate disconnection defect and the gate pattern defect are small, but the amorphous silicon thin film (n + a-Si: H) There is a process limit in which a separate dry etching process must be performed.

Korean public patent 2012-0138290

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems of the prior art, and it is an object of the present invention to provide a multilayer film including at least one film selected from a copper film and a copper alloy film and at least one film selected from the group consisting of a titanium film and a titanium alloy film, (n + a-Si: H) or a metal oxide film can be collectively wet-etched.

The present invention relates to a process for the preparation of a pharmaceutical composition comprising 0.5-20% by weight of persulfate, 0.01-2.0% by weight of a fluorine compound, 1-10% by weight of nitric acid, sulfuric acid, phosphoric acid, perchloric acid or a mixture thereof, 0.5-5% by weight of a cyclic amine compound, 0.1 to 3% by weight of at least one of at least one organic acid selected from the group consisting of malonic acid, lactic acid and malic acid and salts thereof, 0.1 to 3% by weight of sulfonic acid, 0.1 to 3% by weight of copper sulfate, (N + a-Si: H) or a metal oxide film including at least one film selected from a copper film and a copper alloy film and at least one film selected from the group consisting of a titanium film and a titanium alloy film, Wherein the wet etching is carried out by wet etching.

In one embodiment, the persulfate is selected from the group consisting of potassium persulfate (K ₂ S ₂ O ₈ ), sodium persulfate (Na ₂ S ₂ O ₈ ), and ammonium persulfate ((NH ₄ ) ₂ S ₂ O ₈ ) It may be more than one species.

In another embodiment, the fluorine compound is selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, ammonium bifluoride, sodium bifluoride, potassium bifluoride, and the like.

In another embodiment, the cyclic amine compound is an aminotetrazole, an imidazole, an indole, a purine, a pyrazole, a pyridine, a pyrimidine, , Pyrrole, pyrrolidine, and pyrroline. The term " anion "

In another embodiment, the metal oxide film may be an indium gallium zinc oxide (IGZO) film.

The present invention also provides a method of manufacturing a semiconductor device, comprising the steps of: a) forming a gate electrode on a substrate;

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

c) forming a semiconductor layer (n + a-Si: H) on the gate insulating layer;

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

e) forming a pixel electrode connected to the drain electrode, the method comprising the steps of:

Wherein the step a) or the step d) comprises etching each of the electrodes with the etchant composition to form an array substrate for a liquid crystal display.

The etchant composition of the present invention comprises a multilayer film including at least one film selected from a copper film and a copper alloy film, at least one film selected from the group consisting of a titanium film and a titanium alloy film, and an amorphous silicon film (n + a-Si: H ) Or the metal oxide film can be collectively wet-etched so that the whole process time can be shortened and the cost can be reduced.

FIG. 1 shows SEM results of evaluation of etch characteristics according to an experimental example.
FIG. 2 shows the calorific value results according to the experimental example.

The present invention relates to an etching liquid composition and a method of manufacturing an array substrate for a liquid crystal display.

Conventionally, the etchant composition for the copper film system was processed through a wet etching process only to gate and S / D wiring, and the amorphous silicon thin film (n + a-Si: H) as the lower film was processed through a dry etching process. The present invention seeks to simplify the process, and includes one or more films selected from the group consisting of a copper film and a copper alloy film and a film selected from the group consisting of a titanium film and a titanium alloy film, The multilayered film and the amorphous silicon thin film (n + a-Si: H) or the metal oxide film can be collectively wet-etched.

Hereinafter, the present invention will be described in detail.

The present invention relates to a process for the preparation of a pharmaceutical composition comprising 0.5-20% by weight of persulfate, 0.01-2.0% by weight of a fluorine compound, 1-10% by weight of nitric acid, sulfuric acid, phosphoric acid, perchloric acid or a mixture thereof, 0.5-5% by weight of a cyclic amine compound, 0.1 to 3% by weight of at least one of at least one organic acid selected from the group consisting of malonic acid, lactic acid and malic acid and salts thereof, 0.1 to 3% by weight of sulfonic acid, 0.1 to 3% by weight of copper sulfate, (N + a-Si: H) or a metal oxide film including at least one film selected from a copper film and a copper alloy film and at least one film selected from the group consisting of a titanium film and a titanium alloy film, Wherein the wet etching is carried out by wet etching.

The persulfate is contained in an amount of 0.5 to 20 wt% based on the total weight of the etchant composition. If the persulfate content is less than 0.5 wt%, the etching rate may decrease and sufficient etching may not be performed. If the persulfate content is less than 20 wt% If the weight percentage is exceeded, it is difficult to control the etching degree because the etching rate is excessively high, so that the titanium film and the copper film can be overetched.

The persulfate may include, for example, potassium persulfate (K ₂ S ₂ O ₈ ), sodium persulfate (Na ₂ S ₂ O ₈ ), or ammonium persulfate ((NH ₄ ) ₂ S ₂ O ₈ ) , Or a mixture of two or more thereof.

The fluorine compound etches the titanium film and removes residues that may be generated by the etching. The fluorine compound is contained in an amount of 0.01 to 2.0% by weight based on the total weight of the etchant composition. When the content of the fluorine compound is less than about 0.01% by weight, etching of titanium is difficult, while when the content of fluorine compound exceeds 2.0% by weight, occurrence of residue due to titanium etching may increase. If the content of the fluorine compound exceeds 2.0% by weight, the glass substrate on which titanium as well as titanium is laminated can be etched.

The fluorine compound may be, for example, ammonium fluoride, sodium fluoride, potassium fluoride, ammonium bifluoride, sodium bifluoride, or potassium bisulfite and potassium bifluoride. The fluorine compound may include a mixture of two or more of the above.

The nitric acid, sulfuric acid, phosphoric acid, perchloric acid or a mixture thereof is a co-oxidant. The etching rate can be controlled depending on the content of the nitric acid, sulfuric acid, phosphoric acid, perchloric acid, or a mixture thereof in the etchant composition. The nitric acid, sulfuric acid, phosphoric acid, perchloric acid, or a mixture thereof may react with copper ions in the etchant composition, thereby preventing an increase in the copper ion and thereby preventing the etching rate from decreasing. The nitric acid, sulfuric acid, phosphoric acid, perchloric acid or a mixture thereof is contained in an amount of 1 to 10% by weight based on the total weight of the etchant composition. If the content of nitric acid, sulfuric acid, phosphoric acid, perchloric acid, or a mixture thereof is less than 1% by weight, the etching rate is decreased to fail to reach a sufficient etching rate. If the content exceeds 10% by weight, cracks may be generated in the photoresist film Or the photoresist film may be peeled off. When the photoresist layer is cracked or the photoresist layer is peeled, the titanium layer or the copper layer located under the photoresist layer is excessively etched.

The cyclic amine compound is a corrosion inhibitor. The cyclic amine compound is contained in an amount of 0.5 to 5.0% by weight based on the total weight of the etchant composition. If the content of the cyclic amine compound is less than 0.5% by weight, the etching rate of the copper film is increased and there is a risk of overexposure. If the content exceeds 5.0% by weight, the etching rate of copper may be lowered and the desired etching may not be achieved.

The cyclic amine compound may be, for example, an aminotetrazole, an imidazole, an indole, a purine, a pyrazole, a pyridine, a pyrimidine, And may include pyrrole, pyrrolidine or pyrroline. Or the cyclic amine compound may include a mixture of two or more of them.

The at least one organic acid selected from the group consisting of acetic acid, citric acid, malonic acid, lactic acid and malic acid and salts thereof are contained in an amount of 0.1 to 10% by weight based on the total weight of the etching solution composition. The organic acid increases the etching rate as the content in the etchant increases. The salt reduces the etch rate as the content in the etchant increases. In particular, the organic acid salt acts as a chelate to form a complex with the copper ion in the etchant composition to control the etching rate of copper. Therefore, the etch rate can be controlled by controlling the content of the organic acid and the organic acid salt in the etchant to an appropriate level.

If the content of at least one of the organic acid and the organic acid salt is less than 0.1 wt%, it is difficult to control the etching rate of copper, and an excessive angle may occur. If the content is more than 10 wt%, the etching rate of copper lowers, Loses. As a result, the number of substrates to be processed decreases.

The sulfonic acid plays a role in increasing the copper removal performance of the etchant. It acts as a co-oxidant for copper, has no change over time, and stabilizes the chemical liquid. The sulfonic acid may be p-toluenesulfonic acid or methanesulfonic acid.

The copper sulfate accelerates the etching rate of the amorphous silicon thin film (n + a-Si: H) layer. The copper sulfate is contained in an amount of 0.1 to 3% by weight based on the total weight of the etchant composition. If the copper sulfate content is less than 0.1 wt%, the amorphous silicon thin film can not be efficiently etched. If the copper sulfate content exceeds 3 wt%, the amorphous silicon thin film is likely to overeat.

The present invention also provides a method of manufacturing a semiconductor device, comprising the steps of: a) forming a gate electrode on a substrate;

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

c) forming a semiconductor layer (n + a-Si: H) on the gate insulating layer;

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

e) forming a pixel electrode connected to the drain electrode, the method comprising the steps of:

Wherein the step a) or the step d) comprises etching each of the electrodes with the etchant composition to form an array substrate for a liquid crystal display. The array substrate for a liquid crystal display may be a thin film transistor (TFT) array substrate.

Hereinafter, the present invention will be described in more detail with reference to Examples, Comparative Examples and Experimental Examples. However, the following examples, comparative examples and experimental examples are for illustrating the present invention, and the present invention is not limited by the following examples, comparative examples and experimental examples, and can be variously modified and changed.

Example  1 to 5 and Comparative Example  1-2. Etchant  Preparation of composition

The etchant composition was prepared according to the components and contents (unit: wt%) in Table 1 below.

division APS AF HNO ₃ ATZ p-TSA A.A AcOH CuSO ₄ water Example 1 15 0.7 3 1.2 3.0 2.5 8.0 0.2 Balance Example 2 15 0.7 3 1.2 3.0 2.5 8.0 0.4 Balance Example 3 15 0.7 3 1.2 3.0 2.5 8.0 0.6 Balance Example 4 15 0.7 3 1.2 3.0 2.5 8.0 0.8 Balance Example 5 15 0.7 3 1.2 3.0 2.5 8.0 1.0 Balance Comparative Example 1 15 0.7 3 1.2 3.0 2.5 8.0 - Balance Comparative Example 2 15 0.7 3 1.2 0.0 2.5 8.0 - Balance

* APS: Ammonium persulfate

* AF: Ammonium fluoride

* ATZ: 5-aminotetrazole

* p-TSA: p-Toluene Sulfonic Acid

A.A: Ammonium Acetate

AcOH: Acetic acid

Experimental Example . Etch characteristics  evaluation

(1) Etching characteristics of the samples of the etching compositions of Examples 1 to 5 and Comparative Examples 1 and 2 were evaluated for a sample in which an amorphous silicon thin film (n + a-Si: H) and a copper film were sequentially formed. And the results are shown in Table 2 and FIG.

division Etching speed (Å / sec) Example 1 4.6 Example 2 5.9 Example 3 8.5 Example 4 9.7 Example 5 11.7 Comparative Example 1 Not etched Comparative Example 2 Not etched

As shown in Table 2 and FIG. 1, the etchant of Comparative Example 1 not containing copper sulfate (CuSO ₄ ) was unetched (the measured 60 Å corresponds to the error range), whereas in Examples 1 to 5 As the content of copper sulfate increased, the etching rate of N + A-Si layer increased.

The etchant compositions of Comparative Examples 1 and 2 were maintained at a constant temperature of 70 DEG C and then added with 3000 rpm of Cu / Ti powder to measure the amount of heat generated by the presence or absence of p-TSA. And Fig.

division Max calorific value Comparative Example 1 82.8 ° C Comparative Example 2 95.3 DEG C

As shown in Table 3 and FIG. 2, it was confirmed that a large amount of heat was generated when copper was dissolved in the etchant composition without p-TSA.

(2) Etching characteristics were evaluated with the etching composition compositions of Examples 1 to 5 and Comparative Example 1 for the samples in which the IGZO film and the copper film were sequentially formed, and the etching characteristics were observed by SEM. The results are shown in Table 4 .

division Etching speed (Å / sec) Example 1 68 Example 2 76 Example 3 81 Example 4 83 Example 5 102 Comparative Example 1 26

As shown in Table 4, in Examples 1 to 5, the etching rate of the IGZO film was increased as the content of copper sulfate was increased.

Claims (6)

0.5-20% by weight persulfate,
0.01 to 2.0% by weight of a fluorine compound,
1 to 10% by weight of nitric acid, sulfuric acid, phosphoric acid, perchloric acid or a mixture thereof,
0.5 to 5% by weight of a cyclic amine compound,
0.1 to 10% by weight of at least one of at least one organic acid selected from the group consisting of acetic acid, citric acid, malonic acid, lactic acid and malic acid and salts thereof,
0.1 to 3% by weight of sulfonic acid,
0.1 to 3% by weight of copper sulfate, and
Water,
A multilayer film comprising at least one film selected from a copper film and a copper alloy film and at least one film selected from the group consisting of a titanium film and a titanium alloy film,
Wherein the amorphous silicon thin film (n + a-Si: H) or the metal oxide film is collectively wet-etched. The method according to claim 1,
The persulfate is at least one selected from the group consisting of potassium persulfate (K ₂ S ₂ O ₈ ), sodium persulfate (Na ₂ S ₂ O ₈ ) and ammonium persulfate ((NH ₄ ) ₂ S ₂ O ₈ ) ≪ / RTI > The method according to claim 1,
The fluorine compound may be at least one selected from the group consisting of ammonium fluoride, sodium fluoride, potassium fluoride, ammonium bifluoride, sodium bifluoride, and potassium bifluoride. And at least one member selected from the group consisting of The method according to claim 1,
The cyclic amine compound may be an aminotetrazole, an imidazole, an indole, a purine, a pyrazole, a pyridine, a pyrimidine, a pyrrole, , Pyrrolidine, and pyrroline. ≪ Desc / Clms Page number 18 > The method according to claim 1,
Wherein the metal oxide film is an indium gallium zinc oxide (IGZO) film. a) forming a gate electrode on a substrate;
b) forming a gate insulating layer on the substrate including the gate electrode;
c) forming a semiconductor layer (n + a-Si: H) on the gate insulating layer;
d) forming a source / drain electrode on the semiconductor layer; And
e) forming a pixel electrode connected to the drain electrode, the method comprising the steps of:
Wherein the step a) or step d) comprises etching each of the electrodes with the etching composition of claim 1 to form respective electrodes.

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