KR20200105285A - Metal layer etchant composition - Google Patents

Abstract

A metal layer etching composition, according to the present invention, comprises hydrogen oxide, organic acid, glycol-based polymer and water and has a pH range of 3.0 to 4.4. Compared with lower films such as a silicon film and a transparent conductive film, the composition has a high selection ratio or unlimited selection ratio to metal films such as copper and molybdenum. The stability of hydrogen peroxide is also excellent in a relatively high pH range. Even if the composition is reused multiple times due to repeated etching, the initial excellent characteristics can be maintained continuously. Not only can the composition achieve a tape profile with excellent linearity during etching, but the composition also has excellent effects of reducing CD loss and suppressing residue generation. The composition has high stability, so that the composition has increased storage stability which can continuously maintain the excellent initial characteristics before or after use. The composition has the effect of not generating precipitates during etching and being able to suppress heat generation.

Description

Metal layer etchant composition and etching method using the same {Metal layer etchant composition}

The present invention relates to a metal film etching composition.

In general, a thin film transistor (TFT) is used as a circuit board for independently driving each pixel in a liquid crystal display device or an organic EL (Electro Luminescence) display device. The TFT is a thin film transistor in which a scanning signal line or a gate line for transferring a scan signal and an image signal line or a data line for transferring an image signal are formed, and is connected to the gate line and the data line, and a pixel electrode connected to the thin film transistor. Etc. The process of forming the wiring of such a TFT is generally a sputtering process for forming a metal film, a photoresist coating, a photoresist forming process of a desired pattern by exposure and development, an etching process for forming a wiring, and a photoresist that is unnecessary after wiring is formed. It consists of a peeling process to remove it.

Conventionally, aluminum or aluminum alloy layers were commonly used as wiring materials for gates and data line electrodes of TFTs in order to manufacture semiconductor devices and substrates of TFT-LCDs, but it is essential to reduce the resistance of wiring for electrodes to implement a large display. For this, copper and/or molybdenum, which are metals with low resistance, are used to form wiring. Accordingly, studies on etching compositions used for etching wirings containing copper and/or molybdenum are actively being conducted.

In order to etch copper and/or molybdenum-containing wiring, a composition of an etchant having a strong oxidizing power is required. For example, KR10-2018-0077610A discloses a metal film etching composition comprising hydrogen peroxide, a fluorine-containing compound, a tetrazole-based compound, a water-soluble compound having a nitrogen atom and a carboxyl group in one molecule, a sulfate compound, and a polyhydric alcohol-type surfactant. Has been.

However, such a conventional metal film etching composition does not have a high selectivity to a metal film such as copper and/or molybdenum. Therefore, there is a limit to inducing corrosion of a lower film such as a silicon film or a transparent conductive film positioned under the metal film. Therefore, it is difficult to form a precise pattern, the quality is deteriorated, and economical efficiency is poor.

Accordingly, there is a need for a study on a metal film etching composition having a high selectivity for a film of a transition metal such as copper or molybdenum, which can substantially block corrosion of a lower film such as a silicon film and a transparent conductive film.

KR10-2018-0077610A (2018.07.09)

An object of the present invention is to provide a metal film etching composition having a high selectivity or infinite selectivity for a metal film such as copper or molybdenum compared to a lower film such as a silicon film or a transparent conductive film.

An object of the present invention is to provide a metal film etching composition having excellent fruit water stability even in a relatively high pH range.

Another object of the present invention is to provide a metal film etching composition capable of maintaining excellent initial properties continuously even though etching is repeatedly performed and reused a number of times, and thus maintains a low taper angle even when the number of processed sheets increases.

Another object of the present invention is to provide a metal film etching composition that not only can implement a tape profile having excellent linearity during etching, but also has excellent CD loss and suppression properties.

Another object of the present invention is to provide a metal film etching composition having improved storage stability capable of continuously maintaining initial excellent properties even before or after use as the composition has high stability.

Another object of the present invention is to provide a metal film etching composition that does not generate precipitates during etching and can suppress heat generation.

The metal film etching composition according to the present invention includes hydrogen peroxide, an organic acid, a glycol polymer, and water, and has a pH range of 3.0 to 4.4.

In an example of the present invention, the organic acid may include iminodisuccinic acid.

In an example of the present invention, the organic acid may further include any one or two or more selected from malonic acid, glycolic acid, acetic acid, formic acid, citric acid, oxalic acid, butanoic acid, pentanoic acid, propionic acid, tartaric acid, and gluconic acid. have.

In one example of the present invention, the glycol-based polymer may include polyethylene glycol.

The metal film etching composition according to an embodiment of the present invention may include 10 to 40% by weight of hydrogen peroxide, 0.1 to 10% by weight of organic acid, 0.1 to 5% by weight of glycol-based polymer, and the balance of water.

The metal film etching composition according to an embodiment of the present invention may further include any one or two or more ammonium-based compounds selected from ammonium phosphate, ammonium hydrogen phosphate, ammonium superphosphate, ammonium fluoride and ammonium hydrogen fluoride.

The metal film etching composition according to an embodiment of the present invention may further include an azole compound.

The metal film etching composition according to an exemplary embodiment of the present invention may further include any one or two or more overwater stabilizers selected from cyclohexylamine, n-hexylamine, i-hexylamine, and neo-hexylamine.

The metal film etching composition according to an embodiment of the present invention may further include any one or more pH adjusters selected from sodium hydroxide and potassium hydroxide.

The metal film etching composition according to an embodiment of the present invention may include hydrogen peroxide, 5-aminotetrazole, cyclohexylamine, iminodisuccinic acid, iminodiacetic acid, ammonium phosphate, ammonium fluoride, and polyethylene glycol.

The metal film etching composition according to an embodiment of the present invention includes at least one silicon film selected from a silicon oxide film and a silicon nitride film; Or any one or two or more indium oxide films selected from an indium zinc oxide film, an indium tin oxide film, and an indium gallium zinc oxide film; In contrast, any one or more metal films selected from a copper metal film and a molybdenum metal film may be selectively etched with a high selectivity or an infinite selectivity.

In an example of the present invention, the silicon layer may include any one or more selected from a silicon oxide layer and a silicon nitride layer, and the metal layer may include any one or more selected from a copper metal layer and a molybdenum metal layer. have.

The metal film etching method according to the present invention may include etching the metal film using the metal film etching composition.

The metal film etching composition according to the present invention has an effect of having a high selectivity or infinite selectivity for a metal film such as copper or molybdenum compared to a lower film such as a silicon film or a transparent conductive film.

The metal film etching composition according to the present invention has excellent fruit water stability even in a relatively high pH range.

The metal film etching composition according to the present invention can continuously maintain excellent initial characteristics even if etching is repeatedly performed and reused a number of times, and thus, there is an effect of maintaining a low taper angle even when the number of processed sheets increases.

The metal film etching composition according to the present invention not only implements a tape profile having excellent linearity during etching, but also has excellent effects in reducing CD loss and inhibiting occurrence of residues.

As the composition for etching a metal film according to the present invention has high stability, it has an effect of having improved storage stability capable of continuously maintaining initial excellent properties even before or after use.

The metal film etching composition according to the present invention does not generate precipitates during etching, and has an effect of suppressing heat generation.

Even if the effects are not explicitly mentioned in the present invention, the effects described in the specification expected by the technical features of the present invention and the inherent effects thereof are treated as described in the specification of the present invention.

1 is a scanning electron microscope image of a specimen after etching using the etching composition of Example 1 according to the present invention.

Hereinafter, a metal film etching composition according to the present invention and an etching method using the same will be described in detail with reference to the accompanying drawings.

The drawings described in this specification are provided as an example in order to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the present invention is not limited to the drawings to be presented and may be embodied in other forms, and the drawings may be exaggerated to clarify the spirit of the present invention.

Unless otherwise defined, technical terms and scientific terms used in the present specification have the meanings commonly understood by those of ordinary skill in the art to which this invention belongs, and the gist of the present invention in the following description and accompanying drawings A description of known functions and configurations that may unnecessarily obscure will be omitted.

The singular form of terms used in the present specification may be interpreted as including the plural form unless otherwise indicated.

Unless otherwise defined, the unit of% used in this specification means% by weight.

In the present invention, by increasing the etching rate for the film of transition metal such as copper and molybdenum, and in particular, significantly reducing the etching of the film such as a silicon film or a transparent conductive film used as a substrate or a lower film, a very high selectivity or substantial As a result, a metal film etching composition having an infinite selectivity is provided.

The present inventors have made great efforts to minimize the etching of films such as silicon films and transparent conductive films, and as a result, the etching rate for the film is significantly reduced when the film has a specific composition within a specific pH range, and the maximum is 0 Å. It was found that etching can be substantially prevented as /s.

That is, even if the metal film etching composition according to the present invention satisfies a specific pH range to be described later, if the specific composition to be described later is not satisfied, the etching rate for a film such as a silicon film or a transparent conductive film greatly exceeds 0 Å/s. The corrosion of the membrane cannot be prevented to a significant level. In addition, even if the composition satisfies the specific composition, the same applies when the specific pH range is not satisfied.

Specifically, the metal film etching composition according to the present invention includes hydrogen peroxide, an organic acid, a glycol-based polymer and water, and has a pH range of 3.0 to 4.4, so that metals such as copper and molybdenum are compared to films such as a silicon film and a transparent conductive film. It has a high selectivity to the membrane.

It is preferable that the organic acid includes iminodisuccinic acid (IDS). When this is satisfied, that is, when the pH of the above-described range and the composition containing iminodisuccinic acid are satisfied, a high choice for a metal film such as copper or molybdenum compared to a film such as a transparent conductive film containing indium, gallium, or zinc Have a rain Specifically, when an organic acid containing iminodisuccinic acid and a glycol-based polymer are used together, the surface protection effect is maximized as the composition is adsorbed smoothly on the surface of the lower layer of the metal film, thereby maximizing the film such as silicon film and transparent conductive film. In contrast, metal films such as copper and molybdenum may have an infinite selectivity. That is, there is an effect of actually preventing the source of corrosion of a film such as a transparent conductive film containing indium, gallium, or zinc. Conversely, if iminodisuccinic acid is not included, even if a glycol-based polymer is used together, it cannot have an infinite selectivity for a metal film such as copper or molybdenum compared to a film such as the transparent conductive film. For example, among organic acids and glycol-based polymers containing iminodisuccinic acid, when each of them is used alone, that is, when neither of them is used, the infinite selectivity effect does not appear, and only when they are used together is infinite The selectivity effect is implemented. Here, the term “infinite selectivity” means that the etching rate of the silicon layer, transparent conductive layer, etc. is 0 Å/s, so that the etching rate is substantially prevented and the etching rate of metal layers such as copper and molybdenum is substantially etched. Means to have.

As described above, the infinite selectivity effect that occurs by satisfying a specific pH range and a specific composition is that iminodisuccinic acid and glycol-based polymers having cations move onto the surface as the surface of the lower film is negatively charged in the pH range. This may be due to the fact that it facilitates and smoothly performs the role of an etch inhibitor.

The glycol-based polymer is preferably polyethylene glycol (PEG), and more preferably, having a hydroxyl group (-OH) at the terminal may further exert the above-described effect and may be more preferable. The weight average molecular weight of the polyethylene glycol may be liquid or solid at room temperature (25° C.), for example, 150 to 10,000 g/mol, preferably 180 to 2,000 g/mol, and if it is satisfied, too low It is possible to prevent the problem of deteriorating the protective effect of the lower layer due to the weight average molecular weight, and non-uniform etching problems such as layer separation and solubility of the etching composition due to an excessively high weight average molecular weight. When a low-molecular glycol-based compound such as ethylene glycol, propylene glycol, and diethylene glycol is used instead of the glycol-based polymer, the etching rate for the film of transition metals such as copper and molybdenum is significantly reduced, as well as the generation of precipitates, heat generation, and storage. Problems such as poor stability may appear.

The metal film etching composition according to the present invention may further include other types of organic acids other than iminodisuccinic acid. For example, organic acids other than iminodisuccinic acid include any one or two or more selected from iminodiacetic acid, malonic acid, glycolic acid, acetic acid, formic acid, citric acid, oxalic acid, butanoic acid, pentanoic acid, propionic acid, tartaric acid, and gluconic acid. can do. As a specific example, iminodiacetic acid may be further used as an organic acid other than iminodisuccinic acid in terms of etching and stability improvement according to effective chelating. In addition, it may be good in terms of improving etching and stability according to effective etching and chelating of metals such as copper and molybdenum that any one or more organic acids selected from malonic acid and glycolic acid are further used. However, this is only described as a preferred example, and since other organic acids may be further used, the present invention is not necessarily limited thereto and interpreted.

The composition ratio of the metal film etching composition according to an embodiment of the present invention is not limited as it may be appropriately adjusted as long as it can realize the above-described effects, but for example, 10 to 40% by weight of hydrogen peroxide, 0.1 to 10% by weight of organic acid, It may be preferable to include 0.1 to 5% by weight of a glycol-based polymer and the remaining amount of water, and 15 to 35% by weight of hydrogen peroxide, 2 to 8% by weight of an organic acid, 0.2 to 2% by weight of a glycol-based polymer, and the remaining amount of water. May be more desirable. However, this has been described as a preferred example, and the present invention is not necessarily limited thereto.

In the composition according to the present invention, the organic acid containing iminodisuccinic acid among the organic acids is used in an amount of 0.1 to 3% by weight, more preferably 0.2 to 2% by weight, in terms of being able to properly implement the above-described effects. have.

In addition, in the composition according to the present invention, when an organic acid other than iminodisuccinic acid is further used, the organic acid may be preferably used in an amount of 0.5 to 8% by weight, more preferably 1 to 5% by weight, based on the total weight of the composition. . However, this has been described as a preferred example, and the present invention is not necessarily limited thereto.

As a more preferred example, in the composition according to the present invention, the weight ratio of the organic acid containing iminodisuccinic acid and the glycol-based polymer may be 1:0.1 to 2, preferably 1:0.2 to 1.5.

The metal film etching composition according to an embodiment of the present invention may further include any one or two or more ammonium-based compounds selected from ammonium phosphate, ammonium hydrogen phosphate, ammonium superphosphate, ammonium fluoride and ammonium hydrogen fluoride. If this is satisfied, it may be desirable to improve the etching rate of metals such as copper, molybdenum, and molybdenum alloy. In addition, when an ammonium-based compound is further used, it may be more preferable to use two or more different types together. When an ammonium-based compound is used, it may be preferable to use 0.3 to 6% by weight, more preferably 0.5 to 4% by weight, based on the total weight of the composition. At this time, when phosphoric acid compounds such as ammonium phosphate, ammonium hydrogen phosphate, and ammonium superphosphate and fluorinated compounds such as ammonium fluoride and ammonium hydrogen fluoride are used together, 0.5 to 5% by weight of phosphoric acid compound and 0.01 to 0.5% by weight of fluorinated compound It may be better to be used. However, this has been described as a preferred example, and the present invention is not necessarily limited thereto.

The metal film etching composition according to an embodiment of the present invention may further include an azole compound. The azole-based compound is not limited as long as it can suppress the etching rate of the metal layer to form a good etching profile, and can improve the etching inhibiting property of a layer such as a silicon layer or a transparent conductive layer. For example, imidazole , Pyrazole, 1,2,3-triazole, 1,2,4-triazole, tetrazole, pentazole, oxazole, isoxazole, 1,2,3-oxadiazole, oxadiazole, pew Razan, 1,3,4-oxadiazole, thiazole, isothiazole, thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, 1,3,4-thia It may contain any one or two or more selected from diazole and derivatives thereof. Specifically, examples of the azole-based compound include 5-aminotetrazole, 5-methyltetrazole, tetrazole, pyrrole, imidazole, pyrazole, triazole, and pyrrolidine, and 5-aminotetrazole , It may be more preferable to be selected from tetrazole-based compounds such as 5-methyltetrazole and tetrazole. When the azole-based compound is further included, in improving the etching profile for the metal layer and preventing the etching of the silicon layer and the transparent conductive layer, the initial etching prevention performance can be more stably maintained even when the composition is repeatedly used. Can be good in As the amount used of the azole-based compound, it may be preferable that the azole-based compound is contained in an amount of 0.1 to 2% by weight, more preferably 0.2 to 1% by weight, based on the total weight of the composition. However, this has been described as a preferred example, and the present invention is not necessarily limited thereto.

The metal film etching composition according to an exemplary embodiment of the present invention may further include any one or two or more overwater stabilizers selected from cyclohexylamine, n-hexylamine, i-hexylamine, and neo-hexylamine. If this is satisfied, hydrogen peroxide, which is the main component, is stabilized to more stably maintain initial etch prevention performance, and it may be good in terms of stability even in long-term use. When a perhydrate stabilizer is used, it may be preferable to use 0.1 to 2% by weight, more preferably 0.2 to 1% by weight, based on the total weight of the composition. However, this has been described as a preferred example, and the present invention is not necessarily limited thereto.

The metal film etching composition according to an embodiment of the present invention may further include any one or more pH adjusters selected from sodium carbonate, ammonia, sodium hydroxide, potassium hydroxide, and the like. This is used to satisfy the above-described pH range, and the content of the pH adjusting agent may be appropriately adjusted to be within the above-described pH range. In a specific embodiment, the pH adjusting agent may be generally used in an amount of 0.01 to 5% by weight, specifically, 0.1 to 2% by weight, based on the total weight of the composition, but the present invention is not limited thereto.

As described above, the metal film etching composition according to the present invention is excellent in etching a metal film while preventing the etching of a film such as a silicon film and a transparent conductive film.

As a specific example, the etching rate for the metal film of the metal film etching composition according to the present invention may be 10 to 150 Å/sec. As a more specific example, the etching rate for copper may be 70 to 150 Å/sec, specifically 80 to 130 Å/sec, and the etching rate for molybdenum is 10 to 40 Å/sec, specifically 12 to 30 Å/ can be sec.

The silicon layer may be one or more selected from a silicon oxide layer and a silicon nitride layer. However, it goes without saying that there may be an etch prevention effect for various silicon films.

The transparent conductive film is dmlaml that is used in the present technical field, and specifically, an indium zinc oxide (IZO) film, an indium tin oxide (ITO) film, and an indium gallium zinc oxide (ITO) film. Any one or two or more indium-based oxide films selected from IGZO) films and the like may be exemplified. However, it goes without saying that there may be an effect of preventing etching on various transparent conductive layers.

The metal film may be one or two or more selected from copper, molybdenum, titanium, indium, zinc, tin, tungsten, silver, gold, chromium, manganese, iron, cobalt, nickel, and niobium alloys. More specifically, it may be a copper film, a copper/molybdenum film, a copper/titanium film, a copper/molybdenum alloy film, a copper/indium alloy film, more preferably a copper/molybdenum film, a copper/molybdenum alloy film, etc. . However, it goes without saying that there may be an effect of improving etching properties for various transition metals.

As a specific example, the copper/molybdenum film or the copper/molybdenum alloy film may be a multilayer in which at least one copper (Cu) film, at least one molybdenum (Mo) film and/or a molybdenum alloy film (Mo-alloy) are stacked together, the The multilayer may include a Cu/Mo (Mo-alloy) double layer, a Cu/Mo (Mo-alloy)/Cu or a Mo (Mo-alloy)/Cu/Mo (alloy) triple layer. The order of the films can be appropriately adjusted according to the material and bonding properties of the substrate. However, this has been described as a specific example, and the present invention is not necessarily limited thereto.

As a specific example, the molybdenum alloy film is molybdenum-tungsten (Mo-W), molybdenum-titanium (Mo-Ti), molybdenum-niobinium (Mo-Nb), molybdenum-chromium (Mo-Cr), or molybdenum-tantalum ( Mo-Ta), and the molybdenum film or molybdenum alloy film may be deposited to have a thickness of 100 to 500 Å in terms of efficient etching without residue, and the copper film to have a thickness of 1000 to 10,000 Å. However, this has been described as a preferred example, and the present invention is not necessarily limited thereto.

The metal layer according to the present invention may be used in an etching process, and the etching process may be a conventional etching process, and may include, for example, etching the metal layer using the metal layer etching composition.

Specifically, the etching process may include depositing a metal film on a substrate; Patterning after forming a photoresist layer on the metal layer; And etching the metal layer on which the patterned photoresist layer is formed by using the metal layer etching composition according to the present invention. In this case, the metal film formed on the substrate may be a single film, a double metal film, or a multi-metal film (multi-metal film), and in the case of a double metal film or a multi-metal film, the stacking order is not particularly limited.

As a more specific example, the etching process may include forming a semiconductor structure between the substrate and the metal layer, that is, between the substrate and the copper layer or between the substrate and the molybdenum layer in the case of a copper/molybdenum layer. The semiconductor structure may be a semiconductor structure for a display device such as a liquid crystal display device or a plasma display panel. Specifically, the semiconductor structure may include one or more layers selected from a dielectric film, a conductive film, and a silicon film such as amorphous or polycrystalline, and these semiconductor structures may be manufactured according to a conventional method.

Hereinafter, the present invention will be described in detail through examples, but these are for explaining the present invention in more detail, and the scope of the present invention is not limited by the following examples.

The etching composition of Example 1 was prepared by mixing each component with the component contents shown in Table 1 below.

[Examples 2 to 12]

The etching compositions of Examples 2 to 12 were prepared by mixing each component with the component contents shown in Table 1 below.

[Comparative Examples 1 to 11]

The etching compositions of Comparative Examples 1 to 11 were prepared by mixing each component with the component contents shown in Table 1 below.

Ingredient (wt%) H ₂ O ₂ ATZ Glycol compounds Organic acid Ammonium compound Fruit tree stabilizer pH adjuster water pH PEG EG PG DEG IDS IDA MA GA AP AF AS CHA HxA NaOH KOH Example 1 20 0.5 0.5 - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.5 Example 2 20 0.5 0.5 - - - 1.0 3.0 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.7 Example 3 20 0.5 1.0 - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.5 Example 4 20 0.5 0.5 - - - 0.5 3.0 1.5 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.3 Example 5 20 0.5 0.5 - - - 0.5 2.5 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.7 Example 6 20 0.5 0.5 - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - 0.75 - Balance 3.8 Example 7 20 0.5 0.5 - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - 0.30 - Balance 3.2 Example 8 20 0.5 0.5 - - - 0.5 3.0 - One 1.8 0.06 - 0.6 - 0.50 - Balance 3.5 Example 9 20 0.5 0.5 - - - 0.5 3.0 1.0 - 1.8 0.06 - - 0.6 0.50 - Balance 3.5 Example 10 20 0.5 0.5 - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - - 0.5 Balance 3.6 Example 11 20 0.5 0.5 - - - - 3.0 1.0 - 1.8 0.06 - 0.6 - 0.80 - Balance 3.5 Example 12 20 0.5 1.5 - - - - 3.0 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.5 Comparative Example 1 20 0.5 - - - - - 3.0 1.0 - 1.8 0.06 - 0.6 - 0.80 - Balance 3.5 Comparative Example 2 20 0.5 - - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 3.5 Comparative Example 3 20 0.5 - - - - 1.5 3.0 1.0 - 1.8 0.06 - 0.6 - 0.20 - Balance 3.5 Comparative Example 4 20 0.5 0.5 - - - 0.5 3.0 1.0 - - 0.06 1.8 0.6 - 0.50 - Balance 2.5 Comparative Example 5 20 0.5 0.5 - - - 0.5 3.0 1.0 - - 0.06 2.5 0.6 - 0.50 - Balance 2.5 Comparative Example 6 20 0.5 0.5 - - - 0.5 3.0 - - 1.8 0.06 - 0.6 - 0.50 - Balance 4.5 Comparative Example 7 20 0.5 0.5 - - - 0.5 - 1.0 - 1.8 0.06 - 0.6 - 0.50 - Balance 4.5 Comparative Example 8 20 0.5 0.5 - - - 0.5 3.0 1.0 - 1.8 0.06 - 0.6 - - - Balance 2.6 Comparative Example 9 20 0.5 - 0.5 - - 0.5 - - - 1.8 0.06 - 0.6 - 0.50 - Balance 5.0 Comparative Example 10 20 0.5 - - 0.5 - 1.0 - - - 1.8 0.06 - 0.6 - 0.50 - Balance 5.2 Comparative Example 11 20 0.5 - - - 0.5 1.0 - - - 1.8 0.06 - 0.6 - 0.50 - Balance 5.2 H ₂ O ₂ : hydrogen peroxide
ATZ: 5-aminotetrazole
PEG: Polyethyleneglycol (81150, SIGMA-ALDRICH)
EG: Ethylene glycol
PG: Propylene glycol
IDS: Iminodisuccinic acid
IDA: iminodiacetic acid
MA: malonic acid GA: Glycolic acid
AP: ammonium phosphate dibasic
AF: Ammonium fluoride
AS: Ammonium sulfate
CHA: Cyclohexylamine
HxA: Hexylamine
NaOH: sodium hydroxide
KOH: potassium hydroxide

[Experimental Example 1]

<Evaluation of occurrence of precipitates, heat generation, etching performance, and changes over storage time>

Properties of the etching compositions prepared in Examples 1 to 12 and Comparative Examples 1 to 10 were evaluated for occurrence of precipitates, heat generation, etching performance (CD skew, taper), and changes over storage time.

Specifically, a molybdenum alloy film was deposited to a thickness of 300 Å on the lower layers of each of the silicon oxide film, indium zinc oxide film, indium tin oxide film, and indium gallium zinc oxide film, and then a copper film was deposited to a thickness of 6,500 Å thereon. A photolithography process was performed to form a pattern to prepare a specimen. In addition, when the copper content of the etching composition was 3,000, 4,000, and 5,000 ppm during etching, the characteristics of the occurrence of precipitates, heat generation, etching performance, and changes over storage time were evaluated.

The occurrence of precipitates was evaluated as ○ for the occurrence of precipitation fire, and × for the case of no occurrence. For the presence of heat, the case of increasing 5℃ or higher during etching was evaluated as ○, and the case where there was no temperature change as ×. . Etching performance (CD skew, taper) was evaluated by 50% OE based on EPD using mini-etcher equipment. Specifically, when the CD skew is 0.60 µm or more and 1.00 µm or less on one side, the taper is 30 degrees or more and 45 degrees. When it was less than it was judged as a good level. Changes over storage time were evaluated by time period through mini-etcher evaluation to confirm the storage stability of the etching composition and evaluated as good, poor, and very poor (confirmation of change over time: 0-5 days).

The results for this are shown in Table 2 and Table 3 below.

pH Cu Content
(ppm) Etching speed
(Å/sec) Whether precipitates occur Fever or not Etching performance Change over storage time Cu Mo Example 1 3.5 3,000 86 15 × × Good Good 4,000 86 15 × × Good 5,000 88 15 × × Good Example 2 3.7 3,000 84 14 × × Good Good 4,000 83 14 × × Good 5,000 84 14 × × Good Example 3 3.5 3,000 86 15 × × Good Good 4,000 87 15 × × Good 5,000 87 15 × × Good Example 4 3.3 3,000 92 15 × × Good Good 4,000 92 15 × × Good 5,000 92 15 × × Good Example 5 3.7 3,000 90 16 × × Good Good 4,000 90 16 × × Good 5,000 91 16 × × Good Example 6 3.8 3,000 82 17 × × Good Good 4,000 82 17 × × Good 5,000 81 17 × × Good Example 7 3.2 3,000 92 14 × × Good Good 4,000 92 14 × × Good 5,000 93 14 × × Good Example 8 3.5 3,000 85 15 × × Good Good 4,000 85 15 × × Good 5,000 86 15 × × Good Example 9 3.5 3,000 85 13 × × Good Good 4,000 85 13 × × Good 5,000 85 14 × × Good Example 10 3.6 3,000 86 15 × × Good Good 4,000 86 15 × × Good 5,000 87 15 × × Good Example 11 3.5 3,000 90 15 × × Good Bad 4,000 91 15 × × Good 5,000 90 15 ○ ○ Bad Example 12 3.5 3,000 90 15 × × Good Bad 4,000 92 15 × × Good 5,000 91 15 ○ ○ Bad

pH Cu Content
(ppm) Etching speed
(Å/sec) Whether precipitates occur Fever or not Etching performance Change over storage time Cu Mo Comparative Example 1 3.5 3,000 80 13 × × Good Very bad 4,000 85 13 ○ ○ Bad 5,000 92 13 ○ ○ Very bad Comparative Example 2 3.5 3,000 83 12 × × Good Bad 4,000 82 12 × × Good 5,000 92 13 ○ ○ Bad Comparative Example 3 3.5 3,000 85 11 × × Good Bad 4,000 86 11 × × Good 5,000 96 10 ○ ○ Bad Comparative Example 4 2.5 3,000 84 13 × × Good Bad 4,000 84 13 × × Good 5,000 85 13 × × Good Comparative Example 5 2.5 3,000 88 14 × × Good Bad 4,000 88 14 × × Good 5,000 88 15 × × Good Comparative Example 6 4.5 3,000 71 13 ○ ○ Bad Very bad 4,000 68 13 ○ ○ Bad 5,000 61 12 ○ ○ Very bad Comparative Example 7 4.5 3,000 71 14 ○ ○ Bad Very bad 4,000 80 15 ○ ○ Very bad 5,000 88 16 ○ ○ Very bad Comparative Example 8 2.6 3,000 96 10 × × Bad Bad 4,000 96 10 × × Bad 5,000 101 10 × × Bad Comparative Example 9 5.0 3,000 59 13 ○ ○ Very bad Very bad 4,000 53 13 ○ ○ Very bad 5,000 48 13 ○ ○ Very bad Comparative Example 10 5.2 3,000 55 12 ○ ○ Very bad Very bad 4,000 50 12 ○ ○ Very bad 5,000 44 12 ○ ○ Very bad Comparative Example 11 5.2 3,000 57 13 ○ ○ Very bad Very bad 4,000 52 13 ○ ○ Very bad 5,000 47 13 ○ ○ Very bad

As can be seen from Tables 2 and 3, in Examples 1 to 10, no precipitates were generated, no heat generation was observed, the etching performance was good, and long-term storage stability was also excellent. On the other hand, in the comparative examples, it was confirmed that precipitates occur, heat generation occurs, etching performance is not good, long-term storage stability is poor, or two or more of these problems are combined. In particular, from Comparative Examples 9 to 11, even if iminodisuccinic acid and glycol-based compounds are used, it can be confirmed that the effect does not appear when the glycol-based compound is a low-molecular compound such as ethylene glycol, propylene glycol, and diethylene glycol other than polyethylene glycol. have.

[Experimental Example 2]

<Evaluation of the etching selectivity of the metal layer to the lower layer>

The etching selectivity of the metal layer to the lower layer of the etching compositions prepared in Examples 1 to 12 and Comparative Examples 1 to 8 was evaluated. In addition, the presence of molybdenum alloy residue was also evaluated.

Specifically, the thickness before etching of the specimen was measured using an Ellipsometer (J.A WOOLLAM, M-2000U), which is a thin film thickness measuring device. Each etching process was performed on the specimen using each of the etching compositions maintained at an etching temperature of 32° C. in a quartz bath. At this time, the etching time was controlled equally. After the etching was completed, the specimen was washed with ultrapure water, and the remaining etching composition was completely dried using a drying device, and the thickness was measured to evaluate the etching rate. In addition, the molybdenum alloy residue was analyzed through surface observation during SEM analysis.

pH Molybdenum alloy residue Etching speed (Å/s) SiO ₂ SiN _x IZO ITO IGZO Example 1 3.5 none 0 0 0 0 0 Example 2 3.7 none 0 0 0 0 0 Example 3 3.5 none 0 0 0 0 0 Example 4 3.3 none 0 0 0 0 0 Example 5 3.7 none 0 0 0 0 0 Example 6 3.8 none 0 0 0 0 0 Example 7 3.2 none 0 0 0 0 0 Example 8 3.5 none 0 0 0 0 0 Example 9 3.5 none 0 0 0 0 0 Example 10 3.6 none 0 0 0 0 0 Example 11 3.5 none 1.50 1.20 4.00 3.50 4.30 Example 12 3.5 none 1.00 0.80 3.30 2.80 3.85 Comparative Example 1 3.5 none 3.00 2.50 5.00 4.00 5.00 Comparative Example 2 3.5 none 2.50 2.30 3.00 2.50 4.50 Comparative Example 3 3.5 has exist 2.30 2.00 2.70 2.20 4.10 Comparative Example 4 2.5 has exist 2.00 1.50 1.50 1.30 1.60 Comparative Example 5 2.5 has exist 2.00 1.50 1.50 1.30 1.60 Comparative Example 8 2.6 has exist 1.80 1.30 1.30 1.10 1.40 IZO: Indium zinc oxide
ITO: indium tin oxide
IGZO: Indium Gallium Zinc Oxide

As can be seen from Table 4, in Examples 1 to 8, the etching rate of the lower layer of the silicon oxide film, silicon nitride film, indium zinc oxide film, indium tin oxide film, and indium gallium zinc oxide film is 0 Å/ As s, substantially no etching was performed. On the other hand, as the comparative examples have an etching rate of at least 1 Å/s or more, it can be seen that the etching of the lower layer cannot be completely blocked.

In particular, from Example 1, Example 11, Example 12, Comparative Example 2, and Comparative Example 3, when iminodisuccinic acid and polyethylene glycol are used alone, it is difficult to prevent the source of etching of the lower layer, and only when they are used together It can be seen that etching can be prevented from the source.

In addition, from Comparative Examples 4 to 6 and 8, it can be confirmed that even if iminodisuccinic acid and polyethylene glycol are used together, if the pH range does not satisfy 3.0 to 4.4, the source of etching of the lower layer cannot be prevented. have. It is believed that this is due to the fact that iminodisuccinic acid and polyethylene glycol having positive ions move to the surface as the membrane surface is positively charged in the pH range, thereby properly performing the role of an etch inhibitor.

Claims (11)

It contains hydrogen peroxide, organic acid, glycol-based polymer and water,
Metal film etching composition, characterized in that the pH range of 3.0 to 4.4. The method of claim 1,
The organic acid is a metal film etching composition containing iminodisuccinic acid. The method of claim 2,
The organic acid is a metal film etching composition further comprising any one or two or more selected from the group consisting of malonic acid, glycolic acid, acetic acid, formic acid, citric acid, oxalic acid, butanoic acid, pentanoic acid, propionic acid, tartaric acid, and gluconic acid. The method of claim 1,
The glycol-based polymer is a metal film etching composition containing polyethylene glycol. The method of claim 1,
The metal film etching composition is a metal film etching composition comprising 10 to 40% by weight of hydrogen peroxide, 0.1 to 10% by weight of an organic acid, 0.1 to 5% by weight of a glycol-based polymer, and a balance of water. The method of claim 1,
The metal film etching composition further comprises any one or two or more ammonium-based compounds selected from the group consisting of ammonium phosphate, ammonium hydrogen phosphate, ammonium superphosphate, ammonium fluoride and ammonium hydrogen fluoride. The method of claim 1,
The metal layer etching composition further comprises an azole-based compound. The method of claim 1,
The metal film etching composition further comprises any one or two or more overwater stabilizers selected from the group consisting of cyclohexylamine, n-hexylamine, i-hexylamine, and neo-hexylamine. The method of claim 1,
The metal film etching composition further comprises at least one pH adjusting agent selected from the group consisting of sodium hydroxide and potassium hydroxide. The method of claim 2,
The metal layer etching composition may include at least one silicon layer selected from the group consisting of a silicon oxide layer and a silicon nitride layer; Or any one or two or more indium oxide films selected from the group consisting of an indium zinc oxide film, an indium tin oxide film, and an indium gallium zinc oxide film; A metal film etching composition for selectively etching at least one metal film selected from the group consisting of a contrast copper metal film and a molybdenum metal film. A method of etching a metal film comprising the step of etching a metal film using the metal film etching composition of any one of claims 1 to 10.

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