KR101926199B1 - Etchant composition for Ag thin layer and method for fabricating metal pattern using the same - Google Patents

Abstract

The present invention relates to an etchant composition for a multilayer film 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 containing a heterocyclic compound having a carboxyl group will be. 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, Uniform etching characteristics can be exhibited without damages and residues.

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.

KR 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 manufacturing a semiconductor device, which 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 containing a heterocyclic compound having a carboxyl group Thereby providing an etchant composition for a multilayer film.

The etchant composition may further comprise nitric acid, sulfuric acid, persulfate, phosphate and balance water.

The present invention also provides a method of manufacturing a semiconductor device, comprising: forming 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 etching the one or more films formed in the above process with the etching solution 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 phosphoric acid, ferric salt, or oxone as the main oxidizing agent, it improves the long-term storage property, which is a disadvantage of the underlying wiring film and peroxide, , The problem of adsorption of Ag, which occurs when the Ag thin film is etched, is solved.

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

Hereinafter, the present invention will be described in detail.

The present invention relates to a multi-layered 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 containing a heterocyclic compound having a carboxyl group .

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 heterocyclic compound having a carboxyl group contained in the etchant composition of the present invention suppresses the phenomenon of reabsorption of silver lumps generated when 50 or more silver films are etched, thereby improving the number of sheets. The heterocyclic compound having a carboxyl group is added in an amount of 0.1 to 0.8% by weight based on the total weight of the composition, and if it exceeds 0.8% by weight, a uniform uniform etching of the silver film may occur. When it is less than 0.1% by weight, re-adsorption of silver lumps occurs.

The heterocyclic compound having a carboxyl group is a 5- to 10-membered heterocyclic compound having N or O as a heteroatom and may be substituted with an alkyl group having 1 to 10 carbon atoms.

At this time, the carboxyl group may preferably be one or two.

Examples of the heterocyclic compound having a carboxyl group include pyridine carboxylic acid (PCA) or pyridine carboxylic acid (PDCA) compound, such as pyridine dicarboxylic acid (PDCA).

The etchant composition may further comprise nitric acid, sulfuric acid, persulfate, phosphate and balance water.

The nitric acid (HNO ₃ ) is a component used as a main oxidizing agent and functions to wet-etch the silver (Ag) based metal film and the indium oxide film. The content of nitric acid is 7.0 to 13.0% by weight based on the total weight of the composition. If the content of nitric acid is less than 7.0% by weight, the etching rate of the silver film may be lowered and the etching profile may be deteriorated. If the content is more than 13.0% by weight, 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 ) is a component used as a co-oxidant and added in an amount of 4.5 to 10.5 wt% based on the total weight of the total composition, and when added in an excess amount exceeding 10.5 wt% The length is long and is inferior in the process. When the amount is less than 4.5% by weight, etching of the silver film may not be smooth.

The persulfate is preferably used as an oxidizing agent and a reaction initiator in an amount of 12.0 to 17.0% by weight based on the total weight of the composition. If the persulfate is contained in an amount exceeding 17.0% by weight, an overexcitation angle of the indium oxide film may occur. If it is contained in an amount of less than 12.0% by weight, the etching rate of the silver film may decrease and the etching profile may be deteriorated.

The persulfate salt is not particularly limited as long as it is used in the art, but it may be one or more selected from the group consisting of potassium persulfate (PPS), sodium persulfate (SPS) and ammonium persulfate (APS) It is desirable to be species.

The phosphonate allows the indium oxide film to be etched uniformly. Phosphate is added in an amount of 0.5 to 4.0 wt% based on the total weight of the composition, and if it exceeds 4.0 wt%, irregular etching of the indium oxide film may occur. When the amount is less than 0.5% by weight, the etching rate of the indium oxide film may be lowered and the etching profile may be deteriorated.

The phosphate compound is not particularly limited as long as it can be dissociated into phosphate ion in the solution, but it is not limited to ammonium phosphate monobasic, sodium phosphate monobasic, Calcium phosphate monobasic, potassium phosphate monobasic, ammonium phosphate dibasic, sodium phosphate dibasic, calcium phosphate dibasic and secondary phosphate Potassium phosphate dibasic, and the like.

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 OMEGA. 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 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, the heterocyclic compound having nitric acid, sulfuric acid, persulfate, phosphate or carboxyl group can be prepared by a known method, and particularly preferably has purity for semiconductor processing.

As described above, since the etchant composition of the present invention does not use phosphoric acid, ferric salt, or oxone as the main oxidizing agent, it can improve the long-term storage property which is a disadvantage of the underlying wiring film and peroxide, , The addition of the heterocyclic compound having a carboxyl group can solve the problem of adsorption of Ag as a result of etching the Ag thin film.

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 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 step d1), one or more films selected from a silver or silver alloy single film and a multi-layered film composed of the single film and the indium oxide film are deposited on the ohmic contact layer by sputtering and then etched with the etching solution of the present invention, Thereby forming an electrode and a drain electrode. 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 multi-layer film composed of the single film and the indium oxide film are deposited by sputtering and then etched by the etching solution composition of the present invention to form a pixel electrode . 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 Comparative Examples. However, the following examples and comparative examples are provided for illustrating the present invention, and the present invention is not limited by the following examples and comparative examples, and various modifications and changes may be made.

Etchant  Preparation of composition

The composition of the etchant was prepared to be 10 kg in the composition ratio shown in Table 1 below.

(weight%) HNO ₃ H ₂ SO ₄ SPS NHP PDCA water Example 1 10.0 7.0 15 2.0 0.5 65.5 Example 2 7.0 4.5 12.0 0.5 0.1 76.4 Example 3 13.0 10.0 17.0 4.0 0.8 55.2 Comparative Example 1 6.0 3.0 11.0 0.4 - 79.6 Comparative Example 2 14.0 11.0 18.0 5.0 0.9 51.1 Comparative Example 3 10.0 7.0 15 2.0 0.9 65.1

SPS: Sodium peroxysulfate

NHP: Sodium hydrogen phosphate

PDCA: 2,6-Pyridinedicarboxilic acid

Test Example 1 : 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 3 and Comparative Examples 1 to 3 were placed in an experimental apparatus of a spray-type etching method (manufactured by SEMES), and the temperature was set at 30 DEG C and then heated. When the temperature reached 30 +/- 0.1 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. The side etching and the etching characteristics of the degree of occurrence of the etching residue were evaluated using an electronic scanning microscope (SEM; model name: S-4700, manufactured by Hitachi, Ltd.) after cleaning and drying and the results are shown in Table 2 .

Test 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 3 and Comparative Examples 1 to 3 were placed in an experimental apparatus of a spray-type etching method (manufactured by SEMES), and the temperature was set at 30 DEG C and then heated. When the temperature reached 30 +/- 0.1 DEG C, . The total etching time was 5 minutes.

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, etching characteristics of the degree of occurrence of wiring damage were evaluated using an electron scanning microscope (SEM; model: S-4700, manufactured by HITACHI Corporation), and the results are shown in Table 2 below.

division Composition Side Etch (占 퐉) Damage to underlying data wiring The residue Test Example 1 Example 1 0.10 radish radish Test Example 2 Example 2 0.08 radish radish Test Example 3 Example 3 0.13 radish radish Comparative Test Example 1 Comparative Example 1 0.10 U U Comparative Test Example 2 Comparative Example 2 0.01 U U Comparative Test Example 3 Comparative Example 3 0.40 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 3 according to the present invention, good etch characteristics And when the Mo / Al / Mo substrate was etched, it exhibited good etching characteristics in terms of damage to the lower data wiring.

An SEM photograph of the a-ITO / Ag / ITO triple layer after etching the triple layer of the a-ITO / Ag / ITO using the etching composition of Example 1 is shown in Fig. Further, a SEM photograph of the surface of the substrate after the etching of the a-ITO / Ag / ITO triple film using the etching composition of Example 1 and stripping of the photoresist was attached to FIG. FIG. 3 is a SEM photograph of the etching of the a-ITO / Ag / ITO triple layer using the etchant composition of Example 1 and confirming whether the bottom layer was damaged.

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 1 is shown in Fig. An SEM photograph of the surface of the substrate after the etching of the a-ITO / Ag / ITO triple film using the etchant composition of Comparative Example 1 and stripping of the photoresist was attached to 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 1 and confirming whether the lower film was damaged.

As can be seen from the above Table 2, the etchant compositions of Comparative Examples 2 to 3 contain a large amount of sulfuric acid and PDCA, indicating damage to the lower data lines. Further, in the case of the etching solution composition of Comparative Example 1, the content of the oxidizing agent is small and the occurrence of silver residue can be confirmed.

Claims (9)

With respect to the total weight of the composition,
0.1 to 0.8% by weight of a heterocyclic compound having a carboxyl group,
7.0 to 13.0% by weight of nitric acid;
4.5 to 10.5% by weight of sulfuric acid;
12.0 to 17.0 wt% persulfate;
0.5 to 4.0 wt% of phosphate; And
(Ag) or a silver alloy, or a single layer of silver (Ag) or silver alloy and an indium oxide film, which further comprises a residual amount of water. The heterocyclic compound having a carboxyl group according to claim 1, wherein the heterocyclic compound having a carboxyl group is a 5- to 10-membered heterocyclic compound having N or O as a heteroatom, may be substituted with an alkyl group having 1 to 10 carbon atoms, and one or two carboxyl groups Wherein the single layer of silver (Ag) or silver alloy, or the single layer of silver (Ag) or silver alloy and the indium oxide film. The organic electroluminescent device according to claim 1, wherein the heterocyclic compound having a carboxyl group is a pyridinecarboxylic acid compound, a single film of silver (Ag) or silver alloy, or a single film of silver (Ag) Wherein the etchant composition for etching of the multi-layered film comprises: delete The method of claim 1, wherein the persulfate is one selected from the group consisting of potassium persulfate, sodium persulfate, and ammonium persulfate. A silver (Ag) or silver alloy single layer, A single layer of gold and an indium oxide layer. The method of claim 1, wherein the phosphate is selected from the group consisting of ammonium phosphate monobasic, sodium phosphate monobasic, calcium phosphate monobasic, potassium phosphate monobasic, Characterized in that it is at least one selected from the group consisting of ammonium phosphate dibasic, sodium phosphate dibasic, calcium phosphate dibasic and potassium phosphate dibasic. A single layer of silver (Ag) or silver alloy, or a single layer of silver (Ag) or silver alloy and an indium oxide film. (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 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 3, 5 and 6. 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 the one or more films formed in the process with the etching solution composition of any one of claims 1 to 3, 5 and 6 to form respective electrodes. (OLED). 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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