KR101905195B1 - Etchant composition for Ag thin layer and method for fabricating metal pattern using the same - Google Patents

Abstract

The present invention is characterized by comprising 6.0 to 8.0% by weight of nitric acid, 8.0 to 12.0% by weight of sulfuric acid, 8.0 to 10.0% by weight of oxone, 0.5 to 3.0% by weight of organic acid, A single layer of silver (Ag) or silver alloy, or a silver or silver alloy single layer and an indium oxide layer, a method of forming a metal pattern using the same, and an organic light emitting display To a method of manufacturing an array substrate.

Description

[0001] The present invention relates to an etchant composition for a silver thin film and a method for forming a metal pattern using the same,

The present invention relates to a multilayer film etchant composition comprising a single film of silver (Ag) or silver alloy or a single film of silver (Ag) or silver alloy and an indium oxide film, a method of forming a metal pattern using the same, To an array substrate for an organic light emitting display (OLED).

Organic light emitting diodes (OLEDs) are composed of two opposing electrodes and thin films of organic material having a multilayer semiconducting property therebetween. The organic light emitting device having such a structure uses an organic light emitting phenomenon that converts electric energy into light energy using an organic material. Specifically, electrons and holes injected through an anode and a cathode are recombined in an organic material (single molecule / low molecular weight or polymer) thin film to form an excitation, and light of a specific wavelength Emitting type display device using the generated shape.

Among the recent flat panel display devices, an organic light emitting display (hereinafter referred to as OLED) which is mainly used is a self-light emitting element, and lightweight and thin can be used because a backlight used in a liquid crystal display device which is a non-light emitting element is not required. Compared with liquid crystal displays, it has advantages over viewing angle and contrast ratio, advantageous in terms of power consumption, capable of DC low voltage driving, fast response time, strong internal components, Have.

On the other hand, as the display area of the organic light emitting display becomes larger and larger, the gate lines and the data lines connected to the thin film transistors become longer, thereby increasing the resistance of the wirings. For this reason, the continuous use of chromium (Cr), molybdenum (Mo), aluminum (Al), and alloys thereof, which have been conventionally used, as gates and data wirings used in thin film transistors Which makes it difficult to make the flat panel display large-sized and high-resolution realization. Therefore, in order to solve such a problem of signal delay due to such an increase in resistance, it is necessary to form the gate line and the data line with a material having the lowest possible resistivity.

For this purpose, a multilayer film including a silver (Ag: specific resistance: about 1.59 μΩcm) film, a silver alloy film, a silver film or a silver alloy film having a low resistivity and a high luminance as compared with the metals applied to a flat panel display device, Efforts have been made to realize enlargement of flat panel display devices, high resolution and low power consumption by applying them to wirings and reflectors. As part of such efforts, etchants for these materials are being developed.

However, silver (Ag) is extremely poor in adhesion to an insulating substrate such as glass or a lower substrate such as a semiconductor substrate made of intrinsic amorphous silicon or doped amorphous silicon or the like, lifting or feeling is easily induced. Further, even when a silver (Ag) conductive layer is deposited on a substrate, Ag is excessively etched or non-uniformly etched when a conventional etching solution is used for patterning the same, The side profile of the substrate is poor. Therefore, new etchant solutions to solve these problems have been researched.

For example, Korean Patent No. 10-0579421 proposes a silver etching composition comprising nitric acid, phosphoric acid, acetic acid, a supplementary oxide solubilizer, a small carbonaceous surfactant, and water, wherein the phosphoric acid contained in the composition is a transparent electrode / The silver / transparent electrode film has a function of etching silver and suppressing the corrosion of the transparent electrode film, but has a problem of damaging the lower data wiring. Therefore, there is a need for a silver thin film etchant composition which solves such problems.

Korean Patent No. 10-0579421 B

In order to solve the above problems, the present invention provides a method of etching a multilayer film composed of a single film made of silver (Ag) or silver alloy or a single film of silver (Ag) or silver alloy and an indium oxide film, A method for forming a metal pattern using the same, and an array substrate for an organic light emitting display (OLED) using the etchant composition, which exhibits uniform etching characteristics without causing damage to lower data lines and residues, And a method for producing the same.

In order to achieve the above object, the present invention provides a method of producing a composition comprising 6.0 to 8.0 wt% of nitric acid, 8.0 to 12.0 wt% of sulfuric acid, 8.0 to 10.0 wt% of oxone, 0.5 to 3.0 wt% (Ag) or silver alloy, or a single film of silver (Ag) or silver alloy and an indium oxide film, which is characterized by containing water.

The present invention also relates to a method of manufacturing a semiconductor device, comprising the steps of: (i) depositing one or more films selected from a single film of silver (Ag) or silver alloy and a multilayer film composed of a single film of silver (Ag) ; And

(ii) etching the one or a plurality of the formed films with the etchant composition of the present invention.

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 on the gate insulating layer; d) forming source and drain electrodes on the semiconductor layer; And e) forming a pixel electrode connected to the drain electrode, the method comprising the steps of:

Wherein at least one of the steps a), d) and e) forms a silver or silver alloy monolayer, and a multilayer film composed of a silver or silver alloy monolayer and an indium oxide film And etching each of the electrodes with the etchant composition of the present invention to form respective electrodes. The present invention also provides a method of manufacturing an array substrate for an organic light emitting display (OLED).

The etching solution composition of the present invention is characterized in that the amount of side etching is small in etching a multilayer film composed of a single film of silver (Ag) or silver alloy or a single film of silver (Ag) or silver alloy and an indium oxide film, It exhibits uniform etching characteristics without causing damage and residues, and thus can play an important role in achieving high resolution, large size, and low power consumption of the organic light emitting display device. In addition, since the etchant composition of the present invention does not use a peric salt as a peroxide, it improves long-term storage stability, which is a disadvantage of peroxides, and by using oxone, It is possible to solve the problem of the cumulative number of sheets due to the decrease.

FIG. 1 is an SEM photograph of an a-ITO / Ag / ITO triple film etched using the etchant composition of Example 4 according to the present invention.
2 is an SEM photograph of the substrate surface after etching the a-ITO / Ag / ITO triple layer using the etchant composition of Example 4 of the present invention and stripping the photoresist.
3 is an SEM photograph of an a-ITO / Ag / ITO triple film etched using the etchant composition of Comparative Example 3. Fig.
4 is a SEM photograph of the surface of the substrate after etching the a-ITO / Ag / ITO triple layer using the etchant composition of Comparative Example 3 and stripping the photoresist.
FIG. 5 is a SEM photograph of the etching of the a-ITO / Ag / ITO triple layer using the etchant composition of Example 4 and confirming whether the bottom layer is damaged.
FIG. 6 is a SEM photograph showing a case where the a-ITO / Ag / ITO triple layer is etched using the etchant composition of Comparative Example 3 to confirm whether the bottom layer is damaged.

Hereinafter, the present invention will be described in detail.

The present invention is characterized by comprising 6.0 to 8.0% by weight of nitric acid, 8.0 to 12.0% by weight of sulfuric acid, 8.0 to 10.0% by weight of oxone, 0.5 to 3.0% by weight of organic acid, A single layer of silver (Ag) or silver alloy, or a single layer of silver (Ag) or silver alloy and an indium oxide layer.

The etchant composition of the present invention is characterized in that a single film of silver (Ag) or silver alloy, or a multilayer film composed of a single film of silver (Ag) or silver alloy and an indium oxide film can be simultaneously etched.

In the present invention, the multilayer film composed of a single film of silver (Ag) or silver alloy and an indium oxide film means, for example, a double film of indium oxide / silver film or a triple film of indium oxide / silver film / indium oxide film, Indium means indium tin oxide (ITO), zinc oxide indium (IZO), and the like.

The nitric acid (HNO ₃ ) contained in the etchant composition of the present invention is a component used as a main oxidizing agent and serves to wet-etch the silver (Ag) based metal film and the indium oxide film. The content of the nitric acid is 6.0 to 8.0% by weight based on the total weight of the composition. If the content of nitric acid is less than 6.0 wt%, the etching rate of the silver film may be lowered and the etching profile may be deteriorated. If the content is more than 8.0 wt%, the indium oxide / When the triple layer of the indium film is etched, the surface layer of the silver film is exposed, and silver may be removed from the surface of the substrate by the heat treatment in a subsequent process and re-adsorbed.

The sulfuric acid (H ₂ SO ₄ ) contained in the etchant composition of the present invention is a component used as a co-oxidant and added in an amount of 8.0 to 12.0 wt% based on the total weight of the total composition, and an excess amount exceeding 12.0 wt% The etch length is increased due to the high etching rate at the time of the etching, which is bad in the process. When the amount is less than 8.0 wt%, the etching of the silver film may not be smooth.

Oxone (Potassium peroxymonosulfate) contained in the etchant composition of the present invention is an oxidizing agent and a reaction initiator, and plays a role of improving the problem of aging change which is a problem of conventional peroxides.

It is preferable that the composition contains 8.0 to 10.0% by weight based on the total weight of the composition, and if it exceeds 10.0% by weight, an overexcitation angle of the indium oxide film may occur. If it is contained in an amount of less than 8.0 wt%, the etching rate of the silver film may decrease and the etching profile may be deteriorated.

The organic acid contained in the etchant composition of the present invention has a dielectric constant lower than that of water. Thus, the wet etching process improves the wettability of the etchant to the silver film in the wet etching process, thereby achieving more uniform and rapid etching, It plays a role. The organic acid is added in an amount of 0.5 to 3.0% by weight based on the total weight of the composition, and when it exceeds 3.0% by weight, an overexcitation angle of the indium oxide film may occur. When the amount is less than 0.5% by weight, the etching rate of the silver film may decrease and the etching profile may be deteriorated.

The organic acid included in the present invention may be, for example, acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, Malonic acid, methanesulfonic acid, pentanoic acid and oxalic acid may be used alone or in admixture of two or more. Of these, acetic acid is more preferably used.

The water contained in the etchant composition of the present invention is not particularly limited, but deionized water is preferred. In particular, it is more preferable to use deionized water having a resistivity value of water (i.e., the degree of removal of ions in water) of 18 M? / Cm or more. Water used in the present invention is contained in such an amount that the total weight of the composition is 100%.

The etchant composition of the present invention may further include an azole-based compound. The azole compound serves to prevent erosion of the source and drain wirings and may be included in an amount of 0.1 to 1.5% by weight based on the total weight of the etchant composition of the present invention. If the content of the azole compound is less than 0.1% by weight, erosion of the source and drain wirings may occur, resulting in poor processability. If the content of the azole compound exceeds 1.5% by weight, the oxidizing power of the main oxidizing agent is weakened, do.

The azole-based compounds included in the present invention may be selected from the group consisting of aminotetrazole, benzotriazole, tolytriazole, pyrazole, pyrrole, imidazole, And one kind selected from the group consisting of 2-ethylimidazole, 2-ethylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-aminoimidazole, Or two or more, but is not limited thereto.

Since the etchant composition of the present invention does not contain ferric salt, the etchant composition of the present invention has long-term storage effect.

The etchant composition of the present invention may further contain conventional additives in addition to the above-mentioned components, and surfactants, metal ion sequestrants, and corrosion inhibitors may be used as additives.

In the etchant composition of the present invention, nitric acid, sulfuric acid, oxone, and organic acid can be produced according to a conventionally known method, and it is particularly desirable to have purity for semiconductor processing.

Further, according to the present invention,

(i) forming one or a plurality of films selected from a single film of silver (Ag) or silver alloy and a multilayer film composed of a single film of silver (Ag) or silver alloy and an indium oxide film on the substrate; And

(ii) etching the one or more films formed in the above process with the etchant composition of the present invention.

The method of forming a metal pattern according to claim 1, wherein the step (i) comprises the steps of: providing a substrate; forming a single film of silver or silver alloy and a single film of silver (Ag) An indium film, and a multi-layer film composed of an indium film.

The substrate may be a wafer, a glass substrate, a stainless steel substrate, a plastic substrate, or a quartz substrate. As a method of forming a single layer of silver (Ag) or silver alloy on the substrate, or a multilayer film composed of a single layer of silver (Ag) or silver alloy and an indium oxide layer, various methods known to those skilled in the art can be used, It is preferably formed by vacuum deposition or sputtering.

In the step (ii), a photoresist is formed on one or a plurality of films formed in the step (i), the photoresist is selectively exposed using a mask, and the exposed photoresist is post- baking, and the post-baked photoresist is developed to form a photoresist pattern.

The one or more films on which the photoresist pattern is formed are etched using the etchant composition of the present invention to complete the metal pattern.

Further, according to the present invention,

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 on the gate insulating layer;

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

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

Wherein at least one of the steps a), d) and e) is a silver or silver alloy monolayer, and a multilayer film composed of a single film of silver (Ag) or silver alloy and an indium oxide film, Forming a plurality of films, and etching each of the plurality of films with the etchant composition of the present invention to form respective electrodes. The present invention also relates to a method of manufacturing an array substrate for an organic light emitting display (OLED).

The array substrate for the organic light emitting display (OLED) may be a thin film transistor (TFT) array substrate.

In the method of manufacturing an array substrate for an organic light emitting display (OLED) according to the present invention, the step a) may include: a1) forming a silver or silver alloy monolayer on a substrate using a vapor deposition method or a sputtering method, Ag) or a silver alloy and an indium oxide film; And a2) patterning the one or a plurality of the films formed in the above process with the etching solution of the present invention to form a gate electrode. Here, the method of forming one or a plurality of films on the substrate is not limited to the above-described examples.

In the method of manufacturing an array substrate for an organic light emitting display (OLED) according to the present invention, in step (b), silicon nitride (SiN _x ) is deposited on a gate electrode formed on a substrate to form a gate insulating layer. Here, the material used in the formation of the gate insulating layer is not limited to silicon nitride (SiN _x ), but a material selected from various inorganic insulating materials including silicon oxide (SiO ₂ ) may be used to form the gate insulating layer have.

In the method of fabricating an array substrate for an organic light emitting display (OLED) according to the present invention, a semiconductor layer is formed on the gate insulating layer by chemical vapor deposition (CVD) in the step c). That is, an active layer and an ohmic contact layer are sequentially formed, and patterned through dry etching. Here, the active layer is generally formed of pure amorphous silicon (a-Si: H), and the ohmic contact layer is formed of amorphous silicon (n ⁺ a-Si: H) containing impurities. Chemical vapor deposition (CVD) may be used to form the active layer and the ohmic contact layer, but the present invention is not limited thereto.

In the method of manufacturing an array substrate for an organic light emitting diode (OLED) according to the present invention, the step d) includes the steps of: d1) forming source and drain electrodes on the semiconductor layer; And d2) forming an insulating layer on the source and drain electrodes. In the step d1), one or a plurality of films selected from a silver or silver alloy single film and a multilayer film composed of a silver or silver alloy single film and an indium oxide film are deposited on the ohmic contact layer by a sputtering method, And a source electrode and a drain electrode are formed by etching. Here, the method of forming the one or more films on the substrate is not limited to the above-described examples. Wherein d2) step, including the inorganic insulating group, or benzocyclobutene (BCB) and acrylic (acryl) resins (resin) containing silicon nitride (SiN _x) and silicon oxide (SiO ₂₎ on the source and drain electrodes The organic insulating material is selected from the group of organic insulating materials to form an insulating layer as a single layer or a double layer. The material of the insulating layer is not limited to those illustrated above.

In the method of manufacturing an array substrate for an organic light emitting display (OLED) according to the present invention, a pixel electrode connected to the drain electrode is formed in step e). For example, one or a plurality of films selected from a silver or silver alloy single film and a silver / silver alloy single film and an indium oxide film are deposited by sputtering and etched with the etching solution composition of the present invention, . The method of depositing the indium oxide film is not limited to the sputtering method.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following examples and experimental examples are provided to illustrate the present invention, and the present invention is not limited by the following examples and experimental examples, and various modifications and changes may be made.

Example  1 to 5 and Comparative Example  1 to 4

The composition of the etchant was prepared to be 10 kg at the composition ratio shown in the following [Table 1].

nitric acid
(HNO ₃ ) Sulfuric acid
(H ₂ SO ₄₎ Oxone
(Oxone) Organic acid
(Acetic acid)
The azole compound (Azole) water
Example 1 6.0 8.0 8.0 0.5 0.0 77.5 Example 2 6.0 8.0 8.0 0.5 0.1 77.4 Example 3 7.0 9.0 9.0 1.0 0.5 73.5 Example 4 7.0 10.0 10.0 2.0 1.0 70.0 Example 5 8.0 12.0 10.0 3.0 1.5 65.5 Comparative Example 1 5.0 10.0 10.0 2.0 1.0 72.0 Comparative Example 2 7.0 7.0 7.0 2.0 1.0 76.0 Comparative Example 3 5.0 10.0 10.0 2.0 0.0 73.0 Comparative Example 4 7.0 10.0 10.0 3.0 2.0 68.0

(Unit: wt%)

Azole: 5-ATZ (5-aminotetrazole)

Experimental Example  One : Etching  Character rating

The a-ITO / Ag / a-ITO triplet was formed on the substrate and cut into 10 × 10 mm using a diamond knife to prepare a specimen.

The etching composition compositions of Examples 1 to 5 and Comparative Examples 1 to 4 were placed in an experimental apparatus of a spray-type etching system (manufactured by SEMES), and the temperature was set at 40 DEG C, . The total etch time was 50% over etch based on end point detection (EPD).

The substrates were taken out after etching, washed with deionized water, dried using a hot air drying apparatus, and photoresist was removed using a photoresist (PR) stripper. After cleaning and drying, side etching, bottom film damage, and etching property of the etching residue were evaluated using an electron microscope (SEM; model name: S-4700, manufactured by HITACHI Corporation).

Experimental Example  2: Evaluation of lower data wiring damage

A Mo / Al / Mo triple film was formed on the substrate and cut into 10 × 10 mm using a diamond knife to prepare a specimen.

The etching composition compositions of Examples 1 to 5 and Comparative Examples 1 to 4 were placed in an experimental apparatus of a spray-type etching system (manufactured by SEMES), and the temperature was set at 40 DEG C, . The total etching time was 5 minutes.

The substrates were taken out after the process was completed, washed with deionized water, dried using a hot air drying apparatus, and photoresist was removed using a photoresist (PR) stripper. After cleaning and drying, the etching characteristics of the degree of damage of the lower data wiring line were evaluated using an electron microscope (SEM; model: S-4700, manufactured by HITACHI Corporation).

The results of the etching characteristic test are shown in Table 2 below.

Composition Side Etch
(탆) Damage to underlying data wiring The residue Test Example 1 Example 1 0.12 radish radish Test Example 2 Example 2 0.10 radish radish Test Example 3 Example 3 0.29 radish radish Test Example 4 Example 4 0.53 radish radish Test Example 5 Example 5 0.97 radish radish Comparative Test Example 1 Comparative Example 1 0.07 U U Comparative Test Example 2 Comparative Example 2 0.05 U U Comparative Test Example 3 Comparative Example 3 0.00 U U Comparative Test Example 4 Comparative Example 4 0.00 U U

As can be seen from Table 2, when the a-ITO / Ag / a-ITO substrate was etched using the etchant compositions of Examples 1 to 5 according to the present invention, good etch characteristics And etching characteristics of the Mo / Al / Mo substrate showed good etching characteristics in the lower data wiring damage.

An SEM photograph of the a-ITO / Ag / ITO triple layer after etching the triple layer of the a-ITO / Ag / ITO using the etchant composition of Example 4 is shown in Fig. Further, a SEM photograph of the surface of the substrate after etching the a-ITO / Ag / ITO triplet using the etchant composition of Example 4 and stripping the photoresist was shown in Fig. FIG. 5 is a SEM photograph showing the damage of the lower layer by etching the a-ITO / Ag / ITO triple layer using the etchant composition of Example 4. FIG.

As can be seen from Table 2, in the case of the etchant compositions of Comparative Examples 1 to 4, damage to the lower data lines was confirmed.

An SEM photograph of the a-ITO / Ag / ITO triple layer after the etching of the a-ITO / Ag / ITO triple layer using the etchant composition of Comparative Example 3 is shown in Fig. Further, a SEM photograph of the surface of the substrate after the etching of the a-ITO / Ag / ITO triplet using the etchant composition of Comparative Example 3 and stripping of the photoresist was shown in Fig.

FIG. 6 is a SEM photograph showing the damage of the lower film as a result of etching the a-ITO / Ag / ITO triple film using the etchant composition of Comparative Example 3 and confirming whether the lower film is damaged.

Claims (9)

With respect to the total weight of the composition,
6.0 to 8.0 wt% of nitric acid;
8.0 to 12.0% by weight of sulfuric acid;
8.0-10.0 wt% of oxone;
Organic acid 0.5 to 3.0 wt%; And
(Ag) or silver alloy, or a single film of silver (Ag) or silver alloy and an indium oxide film. The method of claim 1, wherein the organic acid is selected from the group consisting of acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, (Ag) or silver alloy, which is a mixture of at least one member selected from the group consisting of malonic acid, methanesulfonic acid, pentanoic acid and oxalic acid. A single layer or a single layer of silver (Ag) or silver alloy and an indium oxide layer. The etchant composition of claim 1, wherein the etchant composition further comprises a single film of silver (Ag) or silver alloy, or a single film of silver (Ag) or silver alloy and an indium oxide film Wherein the etchant composition for etching the multilayered film comprises: The silver halide photographic light-sensitive material as claimed in claim 3, wherein the azole-based compound is contained in an amount of 0.1 to 1.5% by weight based on the total weight of the composition, or a single film of silver (Ag) Film and an indium oxide film. 4. The process of claim 3, wherein the azole compound is selected from the group consisting of aminotetrazole, benzotriazole, tolytriazole, pyrazole, pyrrole, imidazole, And one kind selected from the group consisting of 2-ethylimidazole, 2-ethylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-aminoimidazole, (Ag) or silver alloy, or a single film of silver (Ag) or silver alloy and an indium oxide film, wherein the single layer of silver or silver alloy is at least two kinds of silver or silver alloy. (i) forming one or a plurality of films selected from a single film of silver (Ag) or silver alloy and a multilayer film composed of a single film of silver (Ag) or silver alloy and an indium oxide film on the substrate; And
(ii) etching the one or more films formed in (i) with the etchant composition of any one of claims 1 to 5. 7. The method of claim 6, further comprising forming a photoresist pattern on the one or more films formed. 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 on the gate insulating layer;
d) forming source and drain electrodes on the semiconductor layer; And
(e) forming a pixel electrode connected to the drain electrode, the method comprising the steps of:
Wherein at least one of the steps a), d) and e) forms a silver or silver alloy monolayer, and a multilayer film composed of a silver or silver alloy monolayer and an indium oxide film And etching each of the electrodes with the etching composition according to any one of claims 1 to 5 to form respective electrodes. 9. The method of claim 8, wherein the array substrate for the organic light emitting display (OLED) is a thin film transistor (TFT) array substrate.

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