KR20190057018A - 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 a silver thin-film etching composition and, more specifically, to a silver thin-film etching composition including organic acid, inorganic acid, an etching initiator, and the remaining of water and having an etch stop index of 0.05-0.35, and an etching method and a metal pattern forming method using the same. According to the present invention, the silver thin-film etching composition is capable of having an excellent effect as a thin-film etching composition by having a proper etching speed without re-adsorption.

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 etchant composition comprising an organic acid, an inorganic acid, a etch initiator, and a residual amount of water, and having an Etch stop index of 0.05 to 0.35, an etching method using the same, and a method of forming a metal pattern.

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. .

      Studies have been actively conducted to improve the etching properties. As a representative example thereof, Korean Patent Registration No. 10-579421 discloses a method for producing an etching solution containing nitric acid, phosphoric acid, acetic acid, a supplementary oxide solubilizing agent, Compositions, but still, the art has not completely solved the problems of Ag overexcitation and re-adsorption. Accordingly, there is a demand for an etchant composition having improved etch characteristics for silver, and active research has been conducted in response to a demand. However, the etchant composition having etchant properties remarkably improved as compared with the prior art has not been presented yet to be.

Korean Registered Patent Korean Registered Patent No. 10-0579421

The present invention relates to a process for the production of residues (e. G., Silver residues and / or indium oxide film residues), a single film of silver or silver alloy with reduced side etch, And a silver thin film etchant composition for etching a multilayer film composed of a film and an indium oxide film.

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

Also provided is a method of forming a metal pattern using the silver thin film etchant composition.

In order to achieve the above object,

The present invention relates to a silver thin film etchant composition and an etching method using the same, and more particularly, to a silver thin film etchant composition containing 40 to 65% by weight of organic acid based on the total weight of the composition. 5 to 10% by weight of an inorganic acid; 1 to 15% by weight of an etch initiator; And a balance of water such that the total weight of the composition is 100% by weight.

The present invention also provides a method of manufacturing a semiconductor device, comprising: forming a single layer of silver or silver alloy on a substrate; or a multi-layered film composed of the single layer and the indium oxide layer; Selectively leaving a photoreactive material on the single layer of silver or silver alloy, or on the multi-layered film composed of the single layer and the indium oxide layer; And etching the multilayer film composed of the single film made of silver or silver alloy or the single film and the indium oxide film using the silver thin film etching liquid composition.

Forming a single film made of silver or silver alloy, or a multilayer film composed of said single film and an indium oxide film; Selectively leaving a photoreactive material on the single layer of silver or silver alloy, or on the multi-layered film composed of the single layer and the indium oxide layer; And etching the multi-layered film composed of the single film made of silver or silver alloy or the single film and the indium oxide film using the silver thin film etching solution composition.

The silver thin film etchant composition of the present invention has the problem of the occurrence of residues (e.g., silver residues and / or indium oxide film residues), the side etch is reduced by having an appropriate etch rate without the need for re-adsorption problems, And has excellent effects as a silver thin film etching solution composition for etching a single film or a multilayer film composed of the single film and the indium oxide film.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a composition comprising 40 to 65% by weight of an organic acid, based on the total weight of the composition; 5 to 10% by weight of an inorganic acid; 1 to 15% by weight of an etch initiator; And a balance of water such that the total weight of the composition is 100% by weight.

The present invention relates to a process for the production of residues (e. G., Silver residues and / or indium oxide film residues), a single film of silver or silver alloy with reduced side etch, The present invention has been accomplished on the basis of such an excellent effect as a silver thin film etchant composition for etching a multilayer film composed of a film and an indium oxide film.

The silver thin film etchant composition of the present invention is characterized by being able to etch a single film made of silver (Ag) or a silver alloy, or a multilayer film composed of the single film and the indium oxide film, and the multilayer film can be simultaneously etched.

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

The indium oxide is at least one selected from the group consisting of indium tin oxide (ITO), zinc indium oxide (IZO) and gallium indium zinc oxide (IGZO).

The multilayered film may be a multilayer film formed of indium oxide / silver, indium oxide / silver alloy, indium oxide / silver / indium oxide, indium oxide / silver alloy / indium oxide, In the case of using the etching liquid composition, the problem of occurrence of residues (for example, silver residue and indium oxide film residue) can be prevented from causing side etching by having an appropriate etching rate without causing re-adsorption problem, .

The organic acid contained in the silver thin-film etchant composition of the present invention is a component used as a main oxidizing agent and performs a wet etching by oxidizing silver (Ag) and a transparent conductive film in a transparent conductive film / Ag / transparent conductive film.

The organic acid is contained in an amount of 40 to 65% by weight, preferably 43 to 63% by weight based on the total weight of the silver thin film etchant composition.

If the content of the organic acid is less than 40% by weight based on the total weight of the composition, it may lead to a decrease in the etching rate of silver and a defect due to the generation of silver residue. If the content exceeds 65% by weight, the etching rate of the transparent conductive film, The etching rate becomes too fast, which may cause a problem in the subsequent process due to the occurrence of over-etching.

The organic acid contained in the silver thin film etching solution of the present invention may be at least one selected from the group consisting of acetic acid, butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, methanesulfonic acid, sulfobenzoic acid, And may be at least one selected from the group consisting of salicylic acid, sulfosalicylic acid, benzoic acid, lactic acid, glyceric acid, succinic acid, malic acid, tartaric acid, isocitric acid, propenoic acid, iminodiacetic acid and ethylenediaminetetraacetic acid, It may be more preferable to include

 The inorganic acid contained in the silver thin film etchant composition of the present invention is a component used as an etch-improving agent, and performs a wet etching by oxidizing silver (Ag) and a transparent conductive film in a transparent conductive film / Ag / transparent conductive film.

The inorganic acid is included in an amount of 5 to 10% by weight, preferably 6 to 9% by weight based on the total weight of the silver thin film etchant composition.

When the content of the inorganic acid is less than 5% by weight based on the total weight of the composition, the etching rate of the silver (Ag) and the transparent conductive film is lowered, thereby causing uneven etching uniformity in the substrate, There is a disadvantage that the etch rate of the upper and lower transparent conductive films and the Ag film is accelerated and the overgrown pattern is lost.

The inorganic acid included in the silver thin film etching solution of the present invention may be at least one selected from the group consisting of nitric acid, sulfuric acid and hydrochloric acid.

The etch initiator included in the silver thin film etchant composition of the present invention is a component used as an etch rate modifier and plays a role of accelerating the etch rate of oxides and Ag metals.

The etch initiator is included in an amount of 1 to 15% by weight, preferably 3 to 12% by weight based on the total weight of the silver thin film etchant composition.

If the content of the etching initiator is less than 1 wt%, the etching rate is decreased. If the etching inhibitor content is more than 15 wt%, the etching speed is increased to cause a tip of the upper transparent conductive film, .

The etch initiator included in the silver thin film etching solution of the present invention may be one or more selected from the group consisting of a peroxide initiator, an alkyl metal initiator, and a dislocation metal initiator.

The peroxide initiator may be at least one selected from the group consisting of sodium persulfate, ammonium persulfate, potassium persulfate, oxone, and oxalic acid.

The alkyl metal initiator may be at least one selected from the group consisting of sodium nitrate, potassium nitrate, ammonium nitrate, calcium nitrate, sodium sulfate, potassium sulfate, calcium sulfate, sodium chloride, calcium chloride and potassium chloride.

The dislocation metal initiator may be at least one selected from the group consisting of iron nitrate, ferric nitrate, iron sulfate and ferric sulfate.

The water contained in the silver thin film etchant composition of the present invention uses deionized water for semiconductor processing, preferably water of 18 M OMEGA. / Cm or more, and is contained in a balance such that the total weight of the composition is 100 wt%.

The silver thin film etchant composition of the present invention can be used for a display (OLED, LCD, etc.) TFT array substrate, a TSP trace wiring, and a single film using indium oxide, silver or silver alloy It can be usefully used as a wet etching solution of a multi-layer structure. In addition to the above-mentioned display and TSP, it can be used for an electronic component material using a metal film such as a semiconductor.

Forming a single film made of silver or silver alloy on the substrate, or a multilayer film composed of the single film and the indium oxide film;

Selectively leaving a photoreactive material on the single layer of silver or silver alloy, or on the multi-layered film composed of the single layer and the indium oxide layer; And

And etching the multi-layered film composed of the single film made of silver or silver alloy or the single film and the indium oxide film using the silver thin film etching solution composition.

The present invention also provides a method of manufacturing a semiconductor device, comprising: forming a single film made of silver or silver alloy, or a multilayer film composed of the single film and the indium oxide film; And

Etching the multi-layered film composed of the single film made of silver or silver alloy or the single film and the indium oxide film using the silver thin film etching solution composition.

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 following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

<Preparation of Silver Thin Film Etchant Composition>

Examples 1 to 7 and Comparative Examples 1 to 3

The components shown in Table 1 below were mixed in the respective amounts to prepare a silver thin film etchant composition. Etch stop means etch stop phenomenon which is no longer etched when the condition of the etchant composition changes, and it is also a parameter that predicts that the side etch value does not increase before SEM measurement.

The Etch stop index of the present invention ranges from 0.05 to 0.35 in terms of (inorganic acid + initiator) / (organic acid + water), and the Etch Stop index indicates the ratio of the content of inorganic acid and initiator, , It was predicted that S / E would not increase or not increase due to the ratio.

[Table 1]

(Unit: wt%)

Experimental Example 1 is a performance test of the etchant composition

An ITO / Ag / ITO triple film was formed on the substrate, and an unloading etching process was carried out using an injection type etching equipment (model name: ETCHER (TFT), manufactured by SEMES). The silver etching compositions of Examples 1 to 7 and Comparative Examples 1 to 3 were each put in a temperature of 40 ° C. After the temperature was raised to 40 ° C., the etching process of the ITO / Ag / ITO triplet was performed Respectively. The total etching time was 60 seconds. In the experiment, the initial use time (0 hour) was evaluated with the etchant composition, and after 12 and 24 hours after the evaluation, the same etchant composition was reevaluated.

1. Silver residue measurement

Each of the silver etching compositions of Examples 1 to 12 and Comparative Examples 1 to 17 was placed in an experimental equipment (model name: ETCHER (TFT), manufactured by SEMES) of a spray-type etching system, the temperature was set at 40 占 폚, When the temperature reached 40 +/- 0.1 DEG C, the etching process of the specimen was performed. The total etching time was 60 seconds.

After the substrate was injected and spraying was started, when the etching time of 60 seconds had elapsed, the substrate was taken out, washed with deionized water, dried using a hot air drier, and photoresist was removed using a photoresist stripper. After cleaning and drying, residual silver halide (Ag) was left unetched in a portion not covered with photoresist using an electron microscope (SEM; model name: SU-8010, manufactured by Hitachi) The results are shown in Table 2 below.

<Evaluation Criteria of Residue Measurement>

O: Good [no residue left]

X: Bad [Residual occurrence]

2. Silver adsorption

The silver etching compositions of Examples 1 to 12 and Comparative Examples 1 to 17 were placed in an experimental equipment (model name: ETCHER (TFT), SEMES) of a spray-type etching system, the temperature was set to 40 ° C, When the temperature reached 40 +/- 0.1 DEG C, the etching process of the specimen was performed. The total etching time was 60 seconds.

After the substrate was injected and spraying was started, when the etching time was reached for 60 seconds, the substrate was taken out and washed with deionized water, and then dried using a hot air drying apparatus. 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). The number of Ag adsorbed on the upper Ti of Ti / Al / Ti in the S / D part was measured and evaluated according to the following criteria, and the results are shown in Table 2 below.

&Lt; Silver re-adsorption evaluation standard &

O: Good [less than 50]

X: Bad [more than 50]

3. Etching speed EPD measurement

The etching time EPD was measured by measuring the time that the substrate metal was etched away from the time when the substrate was exposed to the chemical solution using the timer, and the results are shown in Table 2 below.

4. Side Etch Measurement

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). The distance from the patterned PR tip to the etched metal tip was measured. The results are shown in Table 2 below.

[Table 2]

In Examples and Comparative Examples of the present invention, S / E was also increased when the Etch Time was increased in the composition beyond the content range. Etch Stop Index, Etch Stop Index = (inorganic acid + initiator) / (organic acid + water ) And 0.05-0.35, respectively. In addition, it was confirmed that the etching solution composition of the present invention has excellent effects as the silver (Ag) residue, the silver (Ag) adsorption, and the side etch decrease due to the appropriate etching rate.

Claims (1)

Wherein the thin film etchant composition comprises organic acid, inorganic acid, etch initiator, and residual water, and wherein the etch stop index is from 0.05 to 0.35.