KR101926279B1 - Etchant composition for silver thin layer and ehting method and mehtod for fabrication metal pattern using the same - Google Patents

Abstract

The present invention relates to an etchant composition for a silver thin layer, with respect to the whole weight of the composition, which comprises: (a) 7-15 wt% of nitric acid; (B) 3-8 wt% of alkyl sulfonate of the carbon number 1-3; (B-2) 35-65 wt% of organic acid except for the alkyl sulfonate; (C) 5-15 wt% of a sulphate; and (D) remaining water. The sulphate (C) has at least one type selected from a group composed of potassium bisulfate, sodium bisulfate, and magnesium sulfate.

Description

TECHNICAL FIELD [0001] The present invention relates to a thin film etching solution composition, a thin film etching solution composition, and a method of forming a metal pattern using the thin film etching solution composition.

The present invention relates to a silver thin film etching liquid composition, an etching method using the same, and a metal pattern forming method.

As the era of information technology becomes full-scale, the display field for processing and displaying a large amount of information has been rapidly developed, and various flat panel displays have been developed in response to this.

Examples of such flat panel display devices include a liquid crystal display device (LCD), a plasma display panel (PDP), a field emission display (FED), an electroluminescence Display devices (ELD), organic light emitting diodes (OLED), and the like. These flat panel display devices are used for various applications such as computers and mobile phones as well as home appliances such as televisions and videos. These flat panel display devices are rapidly replacing the conventional cathode ray tube (NIT) due to their excellent performance such as reduction in thickness, weight, and power consumption.

In particular, since the OLED emits light by itself and can be driven at a low voltage, it is rapidly applied to a small display market such as a portable device. In addition, OLED is expected to commercialize large-sized TV beyond small-sized display.

On the other hand, conductive metals such as indium tin oxide (ITO) and indium zinc oxide (IZO) have relatively high transmittance to light and have conductivity. Therefore, the electrode of a color filter used in a flat panel display Is widely used. However, these metals also have a high resistance, which is an obstacle to the enlargement of the flat panel display device and the realization of high resolution through improvement of the response speed.

In the case of reflectors, past aluminum (Al) reflectors have been mainly used for products, but in order to realize low power consumption through improvement of luminance, materials are being sought for metal with higher reflectance. For this purpose, a silver (Ag: specific resistance: about 1.59 μΩcm) film having a lower resistivity and a higher luminance than the metals applied to a flat panel display device, a silver alloy or a multilayer film including the same, It is required to develop an etchant for application of this material in order to realize a large-sized flat panel display device and high resolution and low power consumption.

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 peeling is easily induced. Further, even when a silver (Ag) conductive layer is deposited on a substrate, an etchant is used to pattern the same. When a conventional etching solution is used as the etching solution, silver (Ag) is excessively etched or non-uniformly etched to cause lifting or peeling of the wiring, resulting in poor lateral profile of the wiring.

In addition, implementation of low skew for high resolution implementation is difficult in the process.

 In particular, silver (Ag) is a metal that can be easily reduced and must be etched at a high rate so that it is etched without causing residue. At this time, there is no difference in etch rate between the upper and lower portions due to the etching rate. It is difficult to secure the straightness of the etch pattern, and thus it has many limitations in wiring and pattern formation.

When the metal film is standing vertically without a taper angle, voids may be generated between the silver (Ag) and the insulating film or the wiring during the formation of the insulating film or the subsequent wiring in a subsequent process. .

Korean Patent Laid-Open Publication No. 10-2013-0130515 relates to a silver-containing pattern etchant which can simultaneously etch a single film made of silver (Ag) or a silver alloy, and a multilayer film composed of the single film and the transparent conductive film The present invention has been made to solve the problem of the adsorption of residues and silver which are major problems in the related art.

Korean Patent Publication No. 10-2013-0130515

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art described above, and it is an object of the present invention to provide a method for etching a single film made of silver (Ag) or silver alloy and a multilayer film composed of the single film and the transparent conductive film, Silver residue and / or transparent conductive film residue), and silver sorbing problem do not occur in the silver thin film etching solution composition.

It is another object of the present invention to provide a silver thin film etchant composition capable of simultaneously etching the single film and the multilayer film.

It is another object of the present invention to provide a silver thin film etchant composition capable of controlling side etch through control of an etch rate.

It is another object of the present invention to provide a silver thin film etchant composition which can be effectively used for wet etching exhibiting etching uniformity without damaging the lower film.

It is another object of the present invention to provide an etching method using the silver thin film etching solution composition.

Another object of the present invention is to provide a method for forming a metal pattern using the silver thin film etching solution composition.

In order to achieve the above object, the present invention relates to a composition comprising (A) 7 to 15% by weight of nitric acid; (B-1) 3 to 8% by weight of an alkylsulfonic acid having 1 to 3 carbon atoms; 35 to 65% by weight of an organic acid other than the (B-2) alkylsulfonic acid; (C) 5 to 15% by weight of a sulfate; And (D) a residual amount of water, wherein the (C) sulfate includes at least one selected from the group consisting of potassium bisulfate, sodium bisulfate, and magnesium sulfate.

The present invention also provides an etching method using the silver thin film etching solution composition.

The present invention also provides a method for forming a metal pattern using the silver thin film etchant composition.

The silver thin film etchant composition of the present invention is used for etching a single film made of silver (Ag) or a silver alloy and a multilayer film composed of the single film and the transparent conductive film to form a residue (for example, a silver residue and / Film residue and the like) and silver do not cause the problem of re-adsorption.

In addition, the silver thin film etchant composition of the present invention simultaneously etches the single film and the multi-layer film to provide an effect of improving etching efficiency.

In addition, the silver thin film etchant composition of the present invention generates an etch stop phenomenon, thereby controlling the etch rate and controlling the side etch.

In addition, the silver thin film etchant composition of the present invention can be effectively used for wet etching exhibiting etching uniformity without damaging the underlying film.

The present invention relates to a composition comprising (A) 7 to 15% by weight of nitric acid, (B-1) 3 to 8% by weight of an alkylsulfonic acid having 1 to 3 carbon atoms; 35 to 65% by weight of an organic acid other than the (B-2) alkylsulfonic acid; (C) 5 to 15% by weight of a sulfate; And (D) a residual amount of water, wherein the (C) sulfate includes at least one selected from the group consisting of potassium bisulfate, sodium bisulfate, and magnesium sulfate.

The silver thin film etchant composition of the present invention can be used for etching a single film made of silver (Ag) or a silver alloy and a multilayer film composed of the single film and the transparent conductive film, and the residue (for example, silver residue and / Conductive film residue and the like) and silver sorbing problem do not occur.

The silver thin film etchant composition of the present invention can simultaneously etch the single film and the multilayer film.

The silver thin film etchant composition of the present invention can generate an etch stop phenomenon, thereby controlling the etch rate and controlling the side etch.

The silver thin film etchant composition of the present invention is useful for wet etch which exhibits etch uniformity because there is no damage to the underlying film.

The silver alloy may be in the form of an alloy containing silver as a main component and containing other metals such as Nd, Cu, Pd, Nb, Ni, Mo, Ni, Cr, Mg, W, Pa and Ti; A nitride of silver, a silicide, a carbide, an oxide, and the like, but is not limited thereto.

The transparent conductive film may include at least one selected from the group consisting of indium tin oxide (ITO), zinc oxide indium (IZO), zinc tin zinc indium (ITZO), and gallium indium zinc oxide (IGZO).

The multilayered film may include one formed of a transparent conductive film / silver, a transparent conductive film / silver alloy, a transparent conductive film / silver / transparent conductive film, or a transparent conductive film / silver alloy / transparent conductive film.

The silver thin film etchant composition of the present invention can be used for forming an OLED TFT array substrate for a reflective film, a trace wiring for a touch screen panel, or a nanowire wiring, but not limited thereto, Can be used for material.

(A) nitric acid

The nitrate silver contained in the silver thin film etchant composition of the present invention may be used as an oxidizing agent to oxidize the silver thin film and the transparent conductive film.

The content of nitric acid is 7 to 15% by weight, preferably 8 to 12% by weight, based on the total weight of the composition. When the nitric acid is included in the content range, the etching rate can be easily controlled, and the silver thin film and the transparent conductive film can be etched uniformly.

(B) an organic acid

The organic acid contained in the silver thin film etchant composition of the present invention may be used as an etchant for the silver thin film to etch the silver thin film oxidized by the nitric acid.

The organic acid may include (B-1) an alkylsulfonic acid having 1 to 3 carbon atoms and an organic acid other than (B-2) alkylsulfonic acid.

(B-1) an alkylsulfonic acid having 1 to 3 carbon atoms

The alkyl sulfonic acid having 1 to 3 carbon atoms may be, for example, methanesulfonic acid, ethanesulfonic acid or propanesulfonic acid, preferably methanesulfonic acid.

The content of the alkyl sulfonic acid having 1 to 3 carbon atoms may be 3 to 8% by weight based on the total weight of the composition. When the alkyl sulfonic acid having 1 to 3 carbon atoms is contained within the above content range, the control of the etching rate of the silver thin film is easy, and defects due to the formation of silver residue and silver ash can be prevented.

(B-2) an alkylsulfonic acid and an organic acid

Examples of the organic acid other than the alkylsulfonic acid include organic acids such as acetic acid, citric acid, glycolic acid, malonic acid, lactic acid, tartaric acid, butanoic acid, formic acid, gluconic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, One or more, preferably two or more kinds selected from sulfosalicylic acid, benzoic acid, glyceric acid, succinic acid, malic acid, isocitric acid, propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid. In one embodiment, the organic acid other than the alkylsulfonic acid includes one or more, preferably two or more kinds selected from the group consisting of acetic acid, citric acid, glycolic acid, malonic acid, lactic acid and tartaric acid, And citric acid

The content of the organic acid besides the alkylsulfonic acid is 35 to 65% by weight, preferably 45 to 60% by weight based on the total weight of the composition. When the organic acid other than the alkylsulfonic acid is included in the content range, the control of the etching rate of the silver thin film is easy, and defects due to the formation of silver residue and silver ash can be prevented.

(C) Sulfate

The sulfate contained in the silver thin film etchant composition of the present invention can be used to etch the transparent conductive film as an etchant for the transparent conductive film.

In addition, the sulfate contained in the silver thin film etchant composition of the present invention causes an etch stop phenomenon of the silver thin film, and thus it is possible to prevent an increase in side etch even when the etching time is increased in the etching process .

In other words, the silver thin film etchant composition of the present invention includes the above-described sulfate, thereby controlling the occurrence of the etch stop phenomenon, thereby controlling the etch rate and controlling the side etch.

The content of the sulfate is 5-15 wt%, preferably 7-12 wt%, based on the total weight of the composition. When the sulfate is included in the above content range, it is easy to control the etching rate, that is, control of the etching time in the etching process, etch stop phenomenon is regularly expressed, and the silver thin film and the transparent conductive film are uniformly etched .

The sulfate may include at least one selected from the group consisting of potassium sulphate, sodium bisulfate and magnesium sulfate, and may preferably include potassium bisulfate

(D) Water

The water contained in the silver thin film etchant composition of the present invention may be deionized water for semiconductor processing, and preferably deionized water of 18 M / cm or more may be used.

The water content may be included as a balance such that the total weight of the composition is 100% by weight.

The present invention also provides an etching method using the silver thin film etching solution composition according to the present invention.

The etching method comprises the steps of: i) forming a single film made of silver or a silver alloy on the substrate, or a multilayer film composed of the single film and the transparent conductive film; ii) selectively leaving a photoreactive material on the single film or the multilayer film; And iii) etching the single film or the multilayer film using the silver thin film etching liquid composition according to the present invention.

The present invention also provides a method of forming a metal pattern using the silver thin film etchant composition according to the present invention.

The method of forming a metal pattern includes the steps of: i) forming a single film made of silver or a silver alloy on the substrate, or a multilayer film composed of the single film and the transparent conductive film; And ii) etching the single film or the multilayer film using the silver thin film etching liquid composition according to the present invention.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are intended to further illustrate the present invention, and the scope of the present invention is not limited by the following examples. The scope of the present invention is indicated in the claims, and moreover, includes all changes within the meaning and range of equivalency of the claims. In the following Examples and Comparative Examples, "%" and "part" representing the content are on a mass basis unless otherwise specified.

Preparation of silver thin film etchant compositions according to Examples 1 to 5 and Comparative Examples 1 to 10

With reference to the following Table 1, the silver thin film etchant compositions according to Examples 1 to 5 and Comparative Examples 1 to 10 were prepared.

Test Example 1: Side Etch Measurement

ITO (indium tin oxide) / silver / ITO triplet was formed on the substrate, and then the photoresist was patterned on the triplet. The substrate was etched using the silver thin film etchant compositions according to Examples 1 to 5 and Comparative Examples 1 to 10.

Over Etch (O / E) was performed at 40%, 70%, and 100% based on the end of the etching of the region where the photoresist was not patterned in the entire region of the triple layer. The distance from the end of the photoresist to the thin silver film of the triple film was measured using an electron microscope (SEM; model name: SU-8010, Hitachi) and is shown in Table 2 below.

Test Example 2: Measurement of silver (Ag) residue

After forming an ITO / silver / ITO triplet on the substrate, the photoresist was patterned on the triplet.

The silver thin film etchant compositions according to Examples 1 to 5 and Comparative Examples 1 to 10 were placed in an experimental equipment (model name: ETCHER (TFT), SEMES) of a spray-type etch system, the temperature was set to 40, The etching process of the substrate was performed for 85 seconds.

After the etching process was completed, the substrate was rinsed with deionized water, dried using a hot air drying apparatus, and then photoresist was removed using a photoresist stripper (PR stripper). After rinsing and drying, a silver residue (silver halide), which is a phenomenon in which silver remains unetched in the region where the photoresist is not patterned, of the entire region of the triple film, using an electron microscope (SEM; model name: SU-8010, manufactured by Hitachi) And evaluated according to the following criteria, and is shown in Table 2 below.

<Evaluation Criteria of Residue Measurement>

O: Good (no residue)

X: Bad (Residual occurrence)

Test Example 3: Measurement of silver (Ag) re-adsorption

After forming an ITO / silver / ITO triplet on the substrate, the photoresist was patterned on the triplet.

The silver thin film etchant compositions according to Examples 1 to 5 and Comparative Examples 1 to 10 were placed in an experimental equipment (model name: ETCHER (TFT), SEMES) of a spray-type etch system, the temperature was set to 40, The etching process of the substrate was performed for 85 seconds.

After the etching process was completed, the substrate was rinsed with deionized water, dried using a hot air drying apparatus, and then photoresist was removed using a photoresist stripper (PR stripper). After cleaning and drying, the substrate was cut and its cross-section was measured using an electron microscope (SEM; model: SU-8010, manufactured by Hitachi). Due to the etching process, the number of silver particles adsorbed on the upper Ti of the Ti / Al / Ti triplet in the S / D portion exposed in the substrate was measured and evaluated according to the following criteria and shown in Table 2 below .

&Lt; Silver re-adsorption evaluation standard &

O: Good (less than 5)

X: Bad (more than 5)

In the case of performing the etching process using the silver thin film etching solution compositions according to Examples 1 to 5, the side etch was measured to be about 0.2 μm in the entire range of 40 to 100% when overetch was performed, Is not generated.

On the other hand, in the case of performing the etching process using the silver thin film etching solution compositions according to Comparative Examples 1 to 10, it is difficult to control side etch such as etching too much or not etching at all, .

As described above, when the etching process is performed using the silver thin-film etchant composition according to the present invention, it is easy to control the side etch and the silver residue and silver re-adsorption problem do not occur.

Claims (10)

With respect to the total weight of the composition,
(A) 7 to 15% by weight of nitric acid;
(B-1) 3 to 8% by weight of an alkylsulfonic acid having 1 to 3 carbon atoms;
35 to 65% by weight of an organic acid other than the (B-2) alkylsulfonic acid;
(C) 5 to 15% by weight of a sulfate; And
(D) a water balance,
The silver thin film etchant composition of (C) comprises at least one selected from the group consisting of potassium bisulfate, sodium bisulfate, and magnesium sulfate.
The method according to claim 1,
The silver thin film etchant composition of (B-1) wherein the alkyl sulfonic acid having 1 to 3 carbon atoms is methanesulfonic acid.
The method according to claim 1,
The organic acid other than (B-2) alkylsulfonic acid may be at least one selected from the group consisting of acetic acid, citric acid, malonic acid, butanoic acid, formic acid, gluconic acid, glycolic acid, oxalic acid, pentanoic acid, sulfobenzoic acid, sulfosuccinic acid, sulfophthalic acid, salicylic acid, And at least two selected from the group consisting of benzoic acid, lactic acid, glyceric acid, succinic acid, malic acid, tartaric acid, isocitric acid, propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid.
The method according to claim 1,
Wherein the organic acid other than the (B-2) alkylsulfonic acid comprises acetic acid and citric acid.
The method according to claim 1,
Wherein the organic acid other than the (B-2) alkylsulfonic acid is contained in an amount of 45 to 60% by weight.
The method according to claim 1,
Wherein the silver thin film etchant composition is capable of simultaneously etching a single layer of silver or silver alloy or a multilayer of the single layer and the transparent conductive layer.
The method of claim 6,
Wherein the transparent conductive film is at least one selected from the group consisting of indium tin oxide (ITO), zinc oxide indium (IZO), zinc tin oxide indium (ITZO) and gallium gallium indium zinc oxide (IGZO) .
The method of claim 6,
Wherein the multilayer film comprises a transparent conductive film / silver, a transparent conductive film / silver alloy, a transparent conductive film / silver / transparent conductive film, or a transparent conductive film / silver alloy / transparent conductive film.
Forming a single film made of silver or a silver alloy on the substrate, or a multilayer film composed of the single film and the transparent conductive film;
Selectively leaving a photoreactive material on the single film or the multilayer film; And
Etching the single film or the multilayer film using the composition of claim 1.
Forming a single film made of silver or a silver alloy on the substrate, or a multilayer film composed of the single film and the transparent conductive film; And
A method for forming a metal pattern, comprising the step of etching the single film or the multilayer film using the composition of claim 1.