KR102092927B1 - Manufacturing method of an array substrate for liquid crystal display - Google Patents

Abstract

The present invention comprises 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 metal oxide film (active layer) on the gate insulating layer; And d) forming a molybdenum metal film (source / drain electrode) on the metal oxide film, wherein d) forming a molybdenum metal film on the metal oxide film, and etching the molybdenum metal film on the etchant composition. And selectively etching using the etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ), B) one or more selected from organic acids and salts thereof, C) cyclic It relates to a method of manufacturing an array substrate for a liquid crystal display, characterized in that it comprises an amine compound, D) sulfonic acid, and E) the remaining amount of water.

Description

Manufacturing method of array substrate for liquid crystal display device {MANUFACTURING METHOD OF AN ARRAY SUBSTRATE FOR LIQUID CRYSTAL DISPLAY}

The present invention minimizes the attack on the lower metal oxide layer in the double layer of molybdenum metal film / metal oxide film for TFT array wiring formation, and forms a taper profile with excellent straightness to the upper molybdenum metal film. , An etchant composition for selectively etching only the upper molybdenum metal film, a method of forming a wiring using the same, and a method of manufacturing an array substrate for a liquid crystal display device.

As a metal wiring material for a semiconductor device such as TFT-LCD, various metals or alloys thereof are used depending on the type of substrate and required characteristics. For example, Al, Al-Cu, Ti-W, Ti-N, etc. are proposed. For the source / drain wiring of TFT-LCD, Al with low electrical resistance or alloys of these were used a lot.

However, recently, due to reasons such as simplification of the process, cost reduction, and improvement of electrical characteristics due to the enlargement of the substrate, conventional Cr single films, Al or Al alloy single films or multiple films (eg, Mp / Al-Nd double films or Instead of Mp / Al-Nd / Mo triple film), application of a single film made of Mo has been attempted.

On the other hand, the semiconductor layer of the thin film transistor for driving the flat panel display device is mainly formed of amorphous silicon or polycrystalline silicon. Amorphous silicon has an advantage in that the film forming process is simple and the production cost is low, but there is a problem that electrical reliability cannot be secured. , Polycrystalline silicon is very difficult to apply in a large area due to high process temperature, and there is a problem in that uniformity according to the crystallization method cannot be secured.

However, when a semiconductor layer is formed of an oxide, high mobility can be obtained even if it is formed at a low temperature, and the resistance change is large depending on the oxygen content, so it is very easy to obtain desired physical properties. It attracts great attention.

For example, a method of manufacturing a thin film transistor using a double layer made of a Mo metal film / metal oxide for TFT array wiring formation has been attempted. Therefore, a technology capable of selectively etching only a molybdenum metal film without attacking the lower metal oxide layer It is necessary.

In this regard, Korean Patent Publication No. 2010-0082094 discloses a copper film, a copper alloy film, a titanium film, a titanium film comprising a peroxide, an oxidizing agent, a fluorine-containing compound, an additive and deionized water selected from sodium persulfate, potassium persulfate or mixtures thereof. Disclosed is an etch composition of an alloy film, a molybdenum metal film, a molybdenum alloy film, or a multi-layer film in which these are laminated, and Korean Patent Publication No. 2007-0005275 discloses phosphoric acid, nitric acid, inorganic phosphate-based compounds or inorganic nitrate-based compounds, and the remaining amount of water ( H ₂ O) is composed of a Mo, Al, Mo alloy, or a multi-layer film and a single film made of an Al alloy.

However, in the method of manufacturing a thin film transistor using a double layer made of a Mo metal film / metal oxide, the etchant composition may attack the lower metal oxide layer when etching the molybdenum metal film.

Republic of Korea Patent Publication No. 2010-0082094 Republic of Korea Patent Publication 2007-0005275

The present invention has been devised to solve the above-described problems of the prior art, by selectively etching only the upper molybdenum metal film from the double film of the molybdenum metal film / metal oxide film in the wiring formation process of the TFT array, for the lower metal oxide film. An object of the present invention is to provide an etchant composition that minimizes attack and provides a taper profile superior in straightness to the upper molybdenum metal film.

In addition, an object of the present invention is to provide a method of forming a wiring using the etchant composition and a method of manufacturing an array substrate for a liquid crystal display device.

The present invention

The present invention is based on the total weight of the composition,

A) 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ );

B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof;

C) 0.1 to 5.0% by weight of a cyclic amine compound;

D) 0.5 to 5.0 weight percent sulfonic acid; And

E) contains the remaining amount of water,

It provides an etchant composition characterized in that the upper molybdenum metal film is selectively etched from the double film of the molybdenum metal film / metal oxide film.

In addition, the present invention

Ⅰ) forming a metal oxide film on the substrate;

Ⅱ) forming a molybdenum metal film on the metal oxide film;

III) selectively leaving a photoreactive material on the molybdenum metal film; And

Ⅳ) selectively etching the molybdenum metal film using an etchant composition,

The etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ) 5.0 to 25.0 wt%; B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) 0.5 to 5.0 weight percent sulfonic acid; And E) a residual amount of 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 metal oxide film (active layer) on the gate insulating layer; And

d) forming a molybdenum metal film (source / drain electrode) on the metal oxide semiconductor layer,

The step d) includes forming a molybdenum metal film on the metal oxide semiconductor layer, and selectively etching the molybdenum metal film using an etchant composition,

The etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ) 5.0 to 25.0 wt%; B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) 0.5 to 5.0 weight percent sulfonic acid; And E) provides a method of manufacturing an array substrate for a liquid crystal display device comprising a residual amount of water.

In the case of using the etching solution composition of the present invention, it is possible to selectively etch only the upper molybdenum metal film from the double film of the molybdenum metal film / metal oxide film formed for forming the wiring of the TFT array, thereby attacking the lower metal oxide film ( Attack) can be minimized.

In addition, since an excellent taper profile, such as straightness, can be formed by controlling the oxidizing power during etching of the molybdenum metal film, the wiring formation process of the TFT array can be performed very efficiently.

The present invention is based on the total weight of the composition,

A) 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ );

B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof;

C) 0.1 to 5.0% by weight of a cyclic amine compound;

D) 0.5 to 5.0 weight percent sulfonic acid; And

E) contains the remaining amount of water,

It relates to an etchant composition characterized in that the upper molybdenum metal film is selectively etched in a double layer of a molybdenum metal film / metal oxide film.

In the present invention, the 'metal oxide film' is usually AxByCzO (A, B, C are each selected from Zn, Cd, Ga, In, Sn, Hf, Zr, Ta, or Ti; x, y and z≥0, Here, two or more of x, y, and z are non-zero combinations of ternary or quaternary oxides, and may be referred to as oxide semiconductor layers or films constituting oxide semiconductor layers.

The etching ratio of the molybdenum metal film: metal oxide film of the etching solution composition of the present invention is 9.9: 0.1 to 10.0: 0.0, preferably 10.0: 0.0. When the lower metal oxide film is etched, the transistor characteristics are changed, so the above etch ratio must be satisfied.

The A) hydrogen peroxide (H ₂ O ₂ ) serves as a main oxidizing agent for etching the upper molybdenum metal film. The A) hydrogen peroxide (H2O2) is contained in 5.0 to 25.0% by weight based on the total weight of the composition, preferably 8.0 to 20.0% by weight. When included below the above-described range, sufficient etching may not be achieved due to insufficient etching power, and when it is included in an amount exceeding 25.0% by weight, the etching speed is generally increased, so process control is difficult.

The B) at least one selected from organic acids and salts thereof is appropriately adjusted to make the environment of the etchant easy to etch the Mo metal film.

At least one selected from the organic acids and salts thereof serves to increase the etching rate of the upper molybdenum metal film, remove residues inevitably from the etching solution, and minimize attack on the lower metal oxide layer. .

At least one selected from the organic acid and salts thereof is included in an amount of 1.0 to 5.0% by weight based on the total weight of the composition, and preferably 2 to 4% by weight. If included below the above-described range, the etching rate of the upper molybdenum metal film is lowered, partial unetching or residue may occur, and the attack of the lower metal oxide may be severe. When included in excess of 5.0% by weight, the upper molybdenum metal film is excessively etched, and the metal film may be lifted off from the substrate.

Specific examples of the organic acid and salts thereof include acetic acid, iminodiacetic acid, ethylenediaminetetraacetic acid, butanoic acid, citric acid, isocitric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, succinic acid, And sulfosuccinic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, malic acid, tartaric acid, and propenic acid. Further, examples of the salt of the organic acid include potassium salt, sodium salt, and ammonium salt of the organic acid.

The C) cyclic amine compound is a component that controls the etching rate and forms a profile when etching the molybdenum film. Specific examples include 5-aminotetrazole, tolytriazole, benzotriazole, methylbenzotriazole, imidazole compounds, indole compounds, purine compounds, pyrazole compounds, pyridine compounds, pyrimidine compounds, blood And roll-based compounds, pyrrolidine-based compounds, and pyrroline-based compounds. These may be used alone or in combination of two or more.

The cyclic amine compound may be included in an amount of 0.1 to 5% by weight based on the total weight of the composition, preferably 0.5 to 3% by weight. In the above content range, an appropriate molybdenum etching rate and a taper angle can be formed, and the side etching amount can be adjusted. When the content is less than 0.1% by weight, it is difficult to sufficiently control the etching rate of molybdenum, and over-etching may occur. If the content is more than 5% by weight, the etching rate of molybdenum is lowered, and thus the etching time in the process is long, which may decrease productivity.

The D) sulfonic acid is a generic term for a compound having -SO ₃ H, and both non-technic acid and non-technic acid (RSO ₃ H) can be used, but it is more preferable to use an organic technology phosphonic acid. The acid aqueous solution is dissociated ^{sokeseoneun-by} _{(RSO 3 H → -RSO 3 +} H +) represents the properties as acid. The sulfonic acid serves to control the etching rate of the Mo metal film by increasing the activity of hydrogen peroxide, and may also serve to lower the taper angle of the etching surface.

In addition, when the sulfonic acid is included in the etching solution composition of the present invention, during etching, soft etching (S / E) is excellent, and the tapered angle and straightness of the etched metal film are excellent.

Examples of the sulfonic acid include amidosulfonic acid, methanesulfonic acid, ethanesulfonic acid, p-Toluenesulfonic acid, trifluoromethanesulfonic acid, and benzene One or two or more selected from the group consisting of sulfonic acid, sulfamic acid and polystyrene sulfonic acid can be preferably used.

The D) sulfonic acid is contained in 0.5 to 5.0% by weight based on the total weight of the composition, preferably 1.0 to 3.0% by weight. When the sulfonic acid is included below the above-mentioned range, the etching rate is lowered, and when it is included above the above-mentioned range, a problem occurs that the etching rate is too fast.

E) water contained in the etching solution composition of the present invention is not particularly limited, but deionized water is preferred. More preferably, it is preferable to use deionized water having a specific resistance value of water (ie, the degree to which ions are removed in water) of 18 Pa · cm or more. The C) water is included in the remaining amount so that the total weight of the composition of the present invention is 100% by weight.

In addition, in addition to the above-described components, conventional additives may be further added, and examples of the additives include metal ion blockers and corrosion inhibitors.

As used in the present invention, A) hydrogen peroxide (H ₂ O ₂ ), B) one or more selected from organic acids and salts thereof C) cyclic amine compounds, D) sulfonic acids, and E) water are commonly used in a known method. It is possible to manufacture, and the etchant composition of the present invention preferably has purity for semiconductor processing.

In addition, the present invention

Ⅰ) forming a metal oxide film on the substrate;

Ⅱ) forming a molybdenum metal film on the metal oxide film;

III) selectively leaving a photoreactive material on the molybdenum metal film; And

Ⅳ) selectively etching the molybdenum metal film using an etchant composition,

The etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ) 5.0 to 25.0 wt%; B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) 0.5 to 5.0 weight percent sulfonic acid; And E) a residual amount of water.

In the wiring forming method of the present invention, the photoreactive material is preferably a conventional photoresist material, and can be selectively left by a conventional exposure and development process.

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 metal oxide film (active layer) on the gate insulating layer; And

d) forming a molybdenum metal film (source / drain electrode) on the metal oxide semiconductor layer,

The step d) includes forming a molybdenum metal film on the metal oxide semiconductor layer, and selectively etching the molybdenum metal film using an etchant composition,

The etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ) 5.0 to 25.0 wt%; B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) 0.5 to 5.0 weight percent sulfonic acid; And E) relates to a method of manufacturing an array substrate for a liquid crystal display device comprising a residual amount of water.

The method of manufacturing an array substrate for a liquid crystal display device of the present invention is characterized by forming a double film of a molybdenum metal film / metal oxide film.

The array substrate for the liquid crystal display device may be a thin film transistor (TFT) array substrate. In addition, the array substrate for a liquid crystal display device includes a molybdenum metal film etched using the etchant composition of the present invention.

The step of etching the molybdenum metal film with the etchant composition may be performed according to a method well known in the art, and may include immersion, shedding, and the like. The temperature during the etching process is generally 20 to 50 ° C, preferably 30 to 45 ° C, and the appropriate process temperature is determined as required by other process conditions and factors.

The time for etching the molybdenum metal film with the etchant composition may vary depending on the temperature and the thickness of the thin film, but is generally several seconds to several tens of minutes.

In addition, the present invention provides an array substrate for a liquid crystal display device including source and drain electrodes etched using the etchant composition.

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are intended to describe the present invention more specifically, and the scope of the present invention will be determined by the technical spirit of the claims to be described later.

Example  1-4: Etchant  Preparation of the composition

Each component was mixed according to the composition shown in Table 1, to prepare etchant compositions of Examples 1 to 4 and Comparative Examples 1 to 2.

Unit:% by weight H ₂ O ₂ Ammonium acetate 5-aminotetrazole DIW molybdenum Metal oxide film Sulfamic acid Etch characteristics Attack Example 1 20 3.0 1.0 3.0 Balance ◎ Nothing Example 2 15 1.0 0.1 0.5 Balance ◎ Nothing Example 3 5 3.0 3.0 5.0 Balance ○ Nothing Example 4 10 5.0 3.0 1.0 Balance ◎ Nothing Comparative Example 1 15 3.0 5.0 - Balance × Nothing Comparative Example 2 5 3.0 5.0 0.5 Balance × Nothing Comparative Example 3 40 One - 0.5 Balance × 有

◎: Very good (CD Skew ≤ 1㎛, Taper Angle: 40 ° ~ 60 °)

○: Excellent (1㎛ <CD Skew ≤ 1.5㎛, Taper Angle: 30 ° ~ 60 °)

△: Good (1.5㎛ <CD Skew ≤ 2㎛, Taper Angle: 20 ° ~ 60 °)

×: Poor (metal film loss and residue)

Test example : Etchant  Evaluation of composition properties

Etching process for a glass substrate in which an IGZO film is deposited as a metal oxide film on the bottom and a molybdenum single film as a molybdenum metal film is deposited on the metal oxide film by using the etching solution compositions of Examples 1 to 4 and Comparative Examples 1 to 2. Was performed. Experimental equipment (model name: ETCHER (TFT), SEMES) of spray-type etching method was used. During the etching process, the temperature of the etchant composition was around 40 ° C, but the appropriate temperature was required by other process conditions and other factors. can be changed. The etching time may vary depending on the etching temperature, but usually proceeds to about 100 seconds. The images of the molybdenum metal film and the metal oxide film etched in the etching process were inspected using SEM (Hitachi Co., Model S-4700).

The etching solutions of Table 1 and Examples 1 to 4 exhibited good etching characteristics as the hydrogen peroxide content increased, and no residue was generated. In particular, it was confirmed that the etching solution of Example 1 has a high hydrogen peroxide content, and thus the etching rate of the molybdenum metal film is increased.

It was confirmed that the etching solution of Comparative Example 1 did not contain sulfonic acid, and thus the rate of etching of molybdenum was lowered, and a portion of the gastronomic part was present, and residues were also generated. The etching solution of Comparative Example 2 had a small amount of fruit tree, so the etching rate was reduced and residue was partially generated. In the case of Comparative Example 3, a metal oxide film attack occurred due to the excessive number of strong oxidizing powers.

Claims (11)

a) forming a gate electrode on the substrate;
b) forming a gate insulating layer on the substrate including the gate electrode;
c) forming a metal oxide film (active layer) on the gate insulating layer; And
d) forming a molybdenum metal film (source / drain electrode) on the metal oxide film,
The step d) includes forming a molybdenum metal film on the metal oxide film, and selectively etching the molybdenum metal film using an etchant composition,
The etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ) 5.0 to 25.0 wt%; B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) 0.5 to 5.0 weight percent sulfonic acid; And E) a residual amount of water. The method according to claim 1,
The method of manufacturing an array substrate for a liquid crystal display device, characterized in that the array substrate for a liquid crystal display device is a thin film transistor (TFT) array substrate. The method according to claim 1,
The metal oxide film is AxByCzO (A, B, and C are each selected from Zn, Cd, Ga, In, Sn, Hf, Zr, Ta, or Ti; x, y, and z≥0, where x, y, z Method of manufacturing an array substrate for a liquid crystal display device, characterized in that it is a film composed of a ternary oxide or a ternary oxide made of a combination of two or more of which are not 0). With respect to the total weight of the composition,
A) 5.0 to 25.0% by weight of hydrogen peroxide (H ₂ O ₂ );
B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof;
C) 0.1 to 5.0% by weight of a cyclic amine compound;
D) 0.5 to 5.0 weight percent sulfonic acid; And
E) contains the remaining amount of water,
An etching solution composition characterized in that the upper molybdenum metal film is selectively etched from the double layer of the molybdenum metal film / metal oxide film. The method according to claim 4,
The etchant composition of the molybdenum metal film: metal oxide film of the etchant composition is 9.9: 0.1 ~ 10.0: 0.0, characterized in that the etchant composition. The method according to claim 4, wherein B) at least one selected from organic acids and salts thereof is acetic acid, iminodiacetic acid, ethylenediaminetetraacetic acid, butanoic acid, citric acid, isocitric acid, formic acid, gluconic acid, glycolic acid, malonic acid, From the group consisting of oxalic acid, pentanoic acid, sulfobenzoic acid, succinic acid, sulfosuccinic acid, salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, malic acid, tartaric acid, propenic acid, and their potassium salts, sodium salts, and ammonium salts Etchant composition, characterized in that selected. The method according to claim 4,
The C) cyclic amine compound is 5-aminotetrazole, tolytriazole, benzotriazole, methylbenzotriazole, imidazole-based compound, indole-based compound, purine-based compound, pyrazole-based compound, pyridine-based compound, pyri Etching liquid composition, characterized in that at least one or two or more selected from the group consisting of a midine-based compound, a pyrrole-based compound, a pyrrolidine-based compound, and a pyrroline-based compound. The method according to claim 4,
The D) sulfonic acid is amidosulfonic acid, methanesulfonic acid, ethanesulfonic acid, p-Toluenesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid (Benzenesulfonic acid), sulfamic acid (sulfamic acid) and polystyrene sulfonic acid (Polystyrene sulfonic acid) is selected from the group consisting of one or two or more etching liquid composition, characterized in that. The etchant composition of claim 4, wherein the etchant composition further comprises a metal ion blocker or a corrosion inhibitor. Ⅰ) forming a metal oxide film on the substrate;
Ⅱ) forming a molybdenum metal film on the metal oxide film;
III) selectively leaving a photoreactive material on the molybdenum metal film; And
Ⅳ) selectively etching the molybdenum metal film using an etchant composition,
The etchant composition, based on the total weight of the composition, A) hydrogen peroxide (H ₂ O ₂ ) 5.0 to 25.0 wt%; B) 1.0 to 5.0% by weight of at least one selected from organic acids and salts thereof; C) 0.1 to 5.0% by weight of a cyclic amine compound; D) 0.5 to 5.0 weight percent sulfonic acid; And E) a residual amount of water. An array substrate for a liquid crystal display device comprising source and drain electrodes etched using the etchant composition of claim 4.