KR20230141720A - Etching composition and etching method using the same - Google Patents

Abstract

The present invention relates to an etching composition and a method of etching a metal film using the same. Specifically, an etching composition that improves the etching characteristics of a single metal film or a multi-metal film, a method of etching a metal film using the same, and an etching composition performed using the etching composition of the present invention. Provides a method for manufacturing a semiconductor device including a process.

Description

Etching composition and etching method using the same {Etching composition and etching method using the same}

The present invention relates to an etching composition and an etching method using the same, and more specifically, to an etching composition, a method of etching a metal film using the same, and a method of manufacturing a semiconductor device including a process performed using the etching composition of the present invention. .

Microcircuits such as semiconductor devices and TFT-LCDs are made by uniformly applying photoresist to a conductive metal film such as aluminum, aluminum alloy, copper and copper alloy, or an insulating film such as silicon oxide or silicon nitride film formed on a substrate, and then forming a pattern. After irradiating light through an engraved mask and developing it to form a photoresist of the desired pattern, the pattern is transferred to the metal film or insulating film below the photoresist by dry or wet etching, and then unnecessary photoresist is removed through a peeling process. It is completed through a series of lithography processes.

To manufacture semiconductor devices and TFT-LCD substrates, aluminum, aluminum alloy layers, and chrome have been commonly used as wiring materials for TFT gate and data line electrodes. However, in order to implement large displays, it is essential to reduce the resistance of electrode wiring. To this end, attempts are being made to use copper, a metal with low resistance, to form wiring.

However, copper has low adhesion to the glass substrate and silicon insulating film and has a problem of diffusing into the silicon film, so titanium, molybdenum, etc. are used as the lower barrier metal of the copper film.

Accordingly, research on etching compositions used for etching the lower barrier metal film and copper film is also being actively conducted.

When the barrier metal is titanium or molybdenum alloy, the etching process has the disadvantage of having to etch only under specific ions or under specific conditions due to the chemical properties of titanium. When the barrier metal is molybdenum, the etching process involves combining the copper film and molybdenum film. It has the disadvantage of poor adhesion. In particular, overetching occurs due to penetration of the etching composition into areas where the adhesion between the copper film and the molybdenum film is poor.

Furthermore, when etching the copper molybdenum film using an etching solution with strong oxidizing power, the etching speed is too fast, causing problems with process margins, and the taper angle of the taper profile must be 90 degrees or greater. This makes subsequent processes difficult, and the linearity of the pattern is also poor.

For example, when simultaneously etching copper/molybdenum alloy, the copper/molybdenum alloy etchant contains a fluorine compound to improve the etching speed of the molybdenum alloy and remove residues of the molybdenum alloy. There is a problem in that these fluorine compounds etch not only the molybdenum alloy, but also the copper/molybdenum alloy glass substrate, which is the lower film of the gate wiring, and SiNx, the lower film of the source and drain wiring. Increased etching of the lower film increases defects due to etch stains in the post-process and rework process and defects due to etch stains in the slimming process.

In addition to the problems described above, various conventional etching compositions still have the problem of deteriorating etching properties, so research on etching compositions that can dramatically improve these problems is required.

Republic of Korea Patent Publication No. 10-2010-0040352

The present invention provides an etching composition, particularly an etching composition that can dramatically improve etching properties by effectively etching a single metal film such as copper or a multi-metal film containing a metal such as copper, and an etching method using the same.

Additionally, the present invention provides a method for manufacturing a semiconductor device including a process performed using the etching composition of the present invention.

The present invention provides an etching composition with surprisingly improved etching performance. The etching composition of the present invention includes hydrogen peroxide; Etching additives that are phosphoric acid-based compounds and sulfuric acid-based compounds; pH adjuster; fluorine compounds; an undercut inhibitor that is adenine, guanine, or mixtures thereof; amine compounds; and a remaining amount of water, wherein the composition includes 10 to 30% by weight of hydrogen peroxide, 0.01 to 5% by weight of an etching additive, and 0.1 to 3% by weight of a pH regulator, based on the total weight of the composition; It is characterized in that it contains 0.01 to 1% by weight of a fluorine compound, 0.01 to 2% by weight of an undercut inhibitor, 0.1 to 5% by weight of an amine compound, and a residual amount of water.

Preferably, the amine compound according to an embodiment of the present invention may be a C4 to C10 alkylamine, a C3 to C10 cycloalkylamine, or a mixture thereof, and more preferably, it may be a straight chain or branched hexyl amine.

The weight ratio of the undercut inhibitor and the amine compound according to one embodiment of the present invention may be 1:5 to 10.

In the etching composition according to an embodiment of the present invention, the weight ratio of the pH adjuster and the etching additive may be 1:1 to 4.

The phosphoric acid-based compound according to an embodiment of the present invention may be phosphoric acid, phosphate, or a mixture thereof, and the sulfuric acid-based compound may be sulfuric acid, sulfate, or a mixture thereof.

The fluorine compound according to an embodiment of the present invention is any one or two or more selected from HF, NaF, KF, AlF ₃ , HBF ₄ , NH ₄ F, NH ₄ HF ₂ , NaHF ₂ , KHF ₂ and NH ₄ BF ₄ You can.

The etching composition according to an embodiment of the present invention may further include one or two or more selected from the group of etching inhibitors and chelating agents.

The etch inhibitor according to an embodiment of the present invention is a heterocyclic compound containing one or two or more heteroatoms selected from oxygen, sulfur, and nitrogen within the molecule, and the chelating agent contains an amino group, a carboxylic acid group, or a phosphonic acid group within the molecule. It may be a compound containing.

Additionally, the present invention provides a method of etching a metal film including the step of etching the metal film by contacting the metal film with an etching composition according to an embodiment of the present invention.

The metal film according to an embodiment of the present invention may include one or two or more selected from copper, molybdenum, titanium, indium, zinc, tin, and niobium.

Additionally, the metal film according to an embodiment of the present invention includes a single metal film containing copper; A copper alloy film including a copper alloy film; and a multilayer film including an upper film containing copper and a molybdenum film or a molybdenum alloy film.

Additionally, the present invention provides a method of manufacturing a semiconductor device including an etching process performed using an etching composition according to an embodiment of the present invention.

The etching composition of the present invention has excellent stability, and has excellent etching performance as there is no change in etching characteristics such as etching speed, etching uniformity, and non-occurrence of undercuts even when the number of treated sheets and processing time increases.

In addition, the etching composition of the present invention not only has an excellent etching speed, but also has significantly improved etching properties such as no residue of metal on the lower film, no heat generated during etching, no undercut, and a low taper angle. .

Therefore, the etching method of a metal film using the etching composition of the present invention can effectively etch a metal single film or a multi-metal film containing metal, etc. at an excellent etching rate.

In addition, the method of manufacturing a semiconductor device including a process performed using the etching composition of the present invention can produce a semiconductor device with improved performance by using the etching composition of the present invention.

“Alkyl” as used in the specification of the present invention consists only of carbon and hydrogen atoms, 1 to 20 carbon atoms (C1-C20 alkyl), 1 to 15 carbon atoms (C1-C15 alkyl), 4 to 10 carbon atoms. refers to a saturated straight or branched hydrocarbon chain radical having atoms (C4-C10 alkyl), preferably 4 to 8 carbon atoms (C4-C8 alkyl), which are attached to the remainder of the molecule by single bonds. Specific examples of alkyl groups include methyl, ethyl, n-propyl, 1-methylethyl (iso-propyl), n-butyl, n-pentyl, 1,1-dimethylethyl (t-butyl), 3-methylhexyl, 2 -Includes methylhexyl, etc.

As used herein, “cycloalkyl” consists only of carbon and hydrogen atoms, preferably 3 to 15 carbon atoms, preferably 3 to 10 carbon atoms, 3 to 9 carbon atoms, 3 to 8 carbon atoms, 3 may include a fused or bridged ring system having from 3 to 7 carbon atoms, 3 to 6 carbon atoms, 3 to 5 carbon atoms, a ring having 4 carbon atoms, or a ring having 3 carbon atoms. Refers to a stable non-aromatic monocyclic or polycyclic hydrocarbon radical. Cycloalkyl rings can be saturated or unsaturated and can be attached to the rest of the molecule by single bonds. Monocyclic radicals include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Polycyclic radicals include, for example, adamantyl, norbornyl, decalinyl, 7,7-dimethyl-bicyclo[2.2.1]heptanyl, and the like.

The present invention provides an etching composition, and in particular, an etching composition that dramatically improves the etching properties of single or multi-metal films containing copper, etc., and at the same time does not generate heat during etching.

The etching composition of the present invention includes hydrogen peroxide; Etching additives that are phosphoric acid-based compounds and sulfuric acid-based compounds; pH adjuster; fluorine compounds; an undercut inhibitor that is adenine, guanine, or mixtures thereof; amine compounds; and a remaining amount of water, wherein the undercut inhibitor and the amine compound may have a weight ratio of 1:5 to 10.

The etching composition of the present invention is a combination of the above compositions, particularly hydrogen peroxide, a pH adjuster, a fluorine compound, an etching additive that is a mixture of a specific compound, an undercut inhibitor of a specific compound, and an amine compound, and at the same time, a combination of a controlled undercut inhibitor and an amine compound. It has surprisingly improved etching properties due to its weight ratio.

Specifically, the etching composition of the present invention, which has the above-mentioned composition combination and controlled weight ratio of specific components, has excellent stability, protects the interface of the single or multi-metal film to be etched, and does not generate heat, thereby improving etching properties to an extreme extent. improve

Preferably, the etching composition of the present invention has improved etching properties by using a mixture of a specific compound, a phosphoric acid-based compound and a sulfuric acid-based compound, as an etching additive. The phosphoric acid-based compound of the present invention may be phosphoric acid, phosphate, or a mixture thereof, and the sulfuric acid-based compound may be sulfuric acid, sulfate, or a mixture thereof. Specifically, the etching composition of the present invention uses a mixture of sulfuric acid and phosphate as an etching additive, and thus has a synergistic effect in etching properties when combined with other compositions other than the etching additive.

The amine compound according to an embodiment of the present invention may be a C4 to C10 alkylamine, a C3 to C10 cycloalkylamine, or a mixture thereof, preferably a C4 to C8 alkylamine, a C3 to C8 cycloalkylamine. Or it may be a mixture thereof.

Preferably, the amine compound according to an embodiment of the present invention may be a straight-chain or branched C5-C7 alkyl amine, and more preferably, it may be a straight-chain or branched hexyl amine.

The undercut inhibitor and the amine compound according to an embodiment of the present invention may have a weight ratio of 1:5 to 10.

Based on the total weight of the etching composition according to an embodiment of the present invention, 10 to 30% by weight of hydrogen peroxide, 0.01 to 5% by weight of an etching additive, 0.1 to 3% by weight of a pH regulator, 0.01 to 1% by weight of a fluorine compound, and 0.01 to 2% by weight of an undercut inhibitor. % by weight, it may include 0.1 to 5% by weight of an amine compound and a residual amount of water, preferably 15 to 25% by weight of hydrogen peroxide, 0.1 to 3% by weight of an etching additive, 0.1 to 3% by weight of a pH regulator, and 0.05 to 0.05% by weight of a fluorine compound. It may be 0.5% by weight, 0.05 to 1% by weight of undercut inhibitor, 0.1 to 1% by weight of amine compound, and the remaining amount of water.

Hereinafter, each component of the etching composition according to an embodiment of the present invention will be described in more detail.

a) hydrogen peroxide

In the etching composition of the present invention, hydrogen peroxide acts as a main oxidizing agent for metals or transition metals of metal films.

Hydrogen peroxide according to an embodiment of the present invention may be included in an amount of 10 to 30% by weight based on the total weight of the etching composition. If hydrogen peroxide is included in less than 10% by weight, etching may not occur due to insufficient oxidizing power of the transition metal, and if it is included in more than 30% by weight, the etching rate is too fast, making process control difficult. A desirable etching speed can be achieved to prevent etching residues and etching defects, and in terms of reducing CD loss and easy process control, it can preferably be included at 15 to 25% by weight.

b) Etch additives

The etching additive of the present invention acts as an auxiliary oxidizing agent for transition metals or metals and improves the taper profile. The etching additive of the present invention is a mixture of specific inorganic acids.

The inorganic acid of the present invention may be a phosphoric acid-based compound or a sulfuric acid-based compound. The phosphoric acid-based compound may be any compound containing phosphoric acid, and may be phosphoric acid, phosphate, or a mixture thereof. The sulfuric acid-based compound may also be an inorganic compound containing sulfuric acid. Any acid may be used, and for example, it may be sulfuric acid, sulfate, or a mixture thereof. The sulfate may be ammonium sulfate, ammonium persulfate, sodium sulfate, sodium persulfate, potassium sulfate, or potassium persulfate, but is not limited thereto.

Preferably, the phosphoric acid-based compound according to an embodiment of the present invention is one selected from phosphoric acid, potassium hydrogen phosphate, sodium hydrogen phosphate, ammonium hydrogen phosphate, sodium phosphate, sodium superphosphate, potassium phosphate, potassium superphosphate, ammonium phosphate and ammonium superphosphate. There may be two or more, and the sulfuric acid-based compound may be one or two or more selected from sulfuric acid, ammonium hydrogen sulfate, ammonium persulfate, ammonium persulfate, sodium sulfate, sodium persulfate, potassium sulfate, and potassium persulfate.

Preferably, the etching additive according to an embodiment of the present invention may be a combination of sulfuric acid and phosphate.

The etching additive according to an embodiment of the present invention is 0.01 to 5% by weight based on the total weight of the etching composition, and is preferably 0.1 to 3% by weight in terms of improving the taper profile and suppressing deterioration of etching characteristics due to use of the etching additive. , more preferably 1 to 3% by weight.

c) pH regulator

The pH adjuster according to an embodiment of the present invention may be one or two or more selected from sodium hydroxide, potassium hydroxide, sodium carbonate, and ammonium hydroxide, and is preferably hydroxide. It could be sodium. The pH of the etchant composition can be adjusted to 3 to 5. When the pH of the etchant composition is within the above range, the oxide semiconductor is not etched and the etching of the copper and molybdenum alloy can proceed smoothly. The pH adjuster is preferably included in an amount of 0.1 to 3% by weight based on the total weight of the composition.

The weight ratio of the pH adjuster and the etch additive may be 1 to 1:4.

If the weight ratio of the etching additive does not meet the above range, the etching speed is significantly reduced, and when the number of sheets to be treated increases, heat generation and undercut may occur, and molybdenum etching may be inhibited, resulting in the generation of a residual film.

d) Fluorine compounds

The fluorine compound contained in the etching composition of the present invention improves the etching speed of the molybdenum film when simultaneously etching a dual metal film, for example, a copper/molybdenum film, reduces the tail length, and removes molybdenum residue that is inevitably generated during etching. It works. An increase in the tail of molybdenum can reduce brightness, and if residues remain on the substrate and lower film, they must be removed because they cause electrical shorts, poor wiring, and reduced brightness.

The fluorine compound according to an embodiment of the present invention can be any compound that can dissociate to generate F ^- or HF ₂ ^- , but specific examples include HF, NaF, KF, AlF ₃ , HBF ₄ , NH ₄ F, It may be one or two or more selected from NH ₄ HF ₂ , NaHF ₂ , KHF ₂ and NH ₄ BF ₄ , preferably one or two selected from HF, A1F ₃ , HBF ₄ , NH ₄ F, and NH ₄ HF ₂ It could be more than that. The fluorine compound is contained in an amount of 0.01 to 1% by weight based on the total weight of the etching composition, preferably 0.05 to 0.5% by weight in order to effectively remove metal residues, such as molybdenum residues from copper/molybdenum films, and to suppress etching of lower films such as glass substrates. It may be included in weight percent.

e) Undercut inhibitor

The undercut inhibitor included in the etching composition according to an embodiment of the present invention uses a specific compound, adenine, guanine, or a mixture thereof, and is the most preferred combination with a specific etching additive and an amine compound of the present invention. It is a compound that was intentionally selected.

Due to this combination of the present invention, the etching composition of the present invention does not reduce the etching rate, does not generate heat during etching, and does not generate metal residue, thereby surprisingly improving the etching properties.

In particular, when simultaneously etching a metal double film, for example, when simultaneously etching a copper/molybdenum film, molybdenum residue in the molybdenum film can be prevented and undercut occurrence can be suppressed without reducing the etching rate.

The content of the undercut inhibitor of the present invention may be preferably 0.01 to 2% by weight, preferably 0.05 to 1% by weight, based on the total weight of the composition, considering the risk of molybdenum residues, reduction of copper etching rate, and undercut suppression. there is.

f) Amine compounds

The amine compound included in the etching composition of the present invention increases the concentration of metal ions in the etching composition during the etching process, and these metal ions serve as a catalyst to decompose hydrogen peroxide, an oxidizing agent, resulting in changes over time in the entire etching process. By containing an amine compound, the decomposition of hydrogen peroxide is suppressed and changes in the overall etching process over time are suppressed, thereby improving etching characteristics.

Preferably, the amine compound of the present invention may be a C4 to C10 alkylamine, a C3 to C10 cycloalkylamine, or a mixture thereof, but is preferably a C4 to C8 alkylamine, a C3 to C8 cycloalkylamine, or a mixture thereof. It may be linear or branched hexyl amine having 5 to 7 carbon atoms, and more preferably linear or branched hexyl amine. The hexyl amine may be selected from the following compounds. There is no limitation.

The amine compound according to an embodiment of the present invention may preferably be one or two or more selected from n-hexylamine, i-hexylamine, and neo-hexylamine in order to have excellent effects.

The amine compound according to an embodiment of the present invention may be 0.1 to 5% by weight, preferably 0.1 to 1% by weight.

The amine compound and the undercut inhibitor according to an embodiment of the present invention may have a weight ratio of hexyl amine, a specific amine compound: adenine, guanine, or a mixture thereof, which is a specific undercut inhibitor, of 5 to 10:1.

If the ratio of the amine compound is lower than the weight ratio of the amine compound and the undercut inhibitor, the effect of suppressing hydrogen peroxide decomposition is reduced and undercut and heat generation may occur when the number of treated units increases. Additionally, if the ratio of the amine compound is higher than the weight ratio of the amine compound and the undercut inhibitor, molybdenum etching may be inhibited and residual film may be generated.

g) Etch inhibitor

The etching composition according to an embodiment of the present invention may further include an etch inhibitor, and the etch inhibitor controls the etch rate of the transition metal to reduce CD loss of the pattern, increase the process margin, and provide an appropriate taper. To create an etch profile with an angle, it may be a heterocyclic compound containing one or two or more heteroatoms selected from oxygen, sulfur, and nitrogen in the molecule, and the heterocyclic compound of the present invention is a monocyclic heterocyclic compound and It also includes polycyclic heterocyclic compounds having a condensed structure of a monocyclic heterocycle and a benzene ring.

Specific examples of heterocyclic compounds according to an embodiment of the present invention include oxazole, imidazole, pyrazole, triazole, tetrazole , and 5-aminotetrazole. (5-aminotetrazole), methyltetrazole , piperazine, methylpiperazine, hydroxyethylpiperazine, benzimidazole, benzpyrazole , tol It may be tolutriazole, hydrotolutriazole, or hydroxytolutriazole, and is preferably one or two selected from tetrazole, 5-aminotetrazole, and methyltetrazole. It could be more than that.

The etch inhibitor of the present invention may be included in an amount of 0.01 to 5% by weight, preferably 0.05 to 2% by weight, based on the total weight of the etching composition. If the etch inhibitor is included in less than 0.01% by weight, it is difficult to control the etching speed, the ability to control the taper angle is reduced, and the process margin is small, which reduces mass productivity. If it is included in more than 5% by weight, the etching inhibitor is difficult to control, and the ability to control the taper angle is reduced. There is a problem of inefficiency due to reduced speed.

h) Chelating agent

The etching composition according to an embodiment of the present invention may further include a chelating agent, and the chelating agent forms a chelate with metal ions generated during etching to deactivate them, thereby preventing side reactions from occurring due to these metal ions. , As a result, the etching characteristics can be maintained even during repeated etching processes. In particular, in the case of the copper layer, if a large amount of copper ions remain in the etching composition, it forms a passivation film and is oxidized, preventing etching. However, when a chelating agent is added, the formation of a passivation film of copper ions can be prevented. Additionally, the chelating agent can increase the stability of the etching composition by preventing the decomposition reaction of hydrogen peroxide itself. Therefore, if a chelating agent is not added to the etching composition, oxidized metal ions are activated during etching, which may easily change the etching properties of the etching composition, and the decomposition reaction of hydrogen peroxide may be promoted, resulting in heat generation and explosion.

In other words, the chelating agent according to an embodiment of the present invention suppresses the decomposition of hydrogen peroxide by chelating with metal ions generated during the etching process and serves to increase the stability of the etching composition even when stored, and is not particularly limited. , may contain an amino group, a carboxylic acid group, or a phosphonic acid group within the molecule, specifically iminodiacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, and diethylenetrinitrile. Pentaacetic acid (diethylenetrinitri1 acetic acid), aminotris(methylenephosphonic acid), (1-hydroxyethane-1,1-diyl) bis (phosphonic acid) ((1-hydroxyethane-l,1 -diyl)bis (phosphonic acid)), ethylenediamine tetra(methylene phosphonic acid), Diethylenetri amine penta(methylenephosphonic acid), alanine ), glutamic acid, aminobutyric acid, and glycin, preferably one or more selected from iminodiacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, and diethylenetrinitrile penta. It may be one or two or more selected from acetic acid.

The chelating agent according to an embodiment of the present invention may be included in an amount of 0.1 to 5% by weight, preferably 0.1 to 3% by weight, based on the total weight of the etching composition. If the chelating agent is included in less than 0.1% by weight, the amount of metal ions that can be deactivated is too small, so the ability to control the decomposition reaction of hydrogen peroxide is reduced, and if it is included in more than 5% by weight, the action of deactivating the metal through additional chelate formation cannot be expected, making it inefficient. can be a problem.

i) water

In the etching composition according to an embodiment of the present invention, water is not particularly limited, but deionized water may be preferable, and deionized water having a resistivity value of 18 MQ/cm or more, which is the degree to which ions are removed from the water, may be more preferable. .

The water may be included in an amount such that the total weight of the etching composition is 100% by weight.

j) Other additives

The etching composition for a metal film of the present invention may further include any additives commonly used in etching compositions to improve etching performance. The additives include additional etch stabilizers, glass etch inhibitors, and glycol-based polymers. One of these may be used alone or two or more may be used in combination.

The etch stabilizer according to an embodiment of the present invention may be a compound having both an alcohol group and an amine group. As a specific example, it may be any one or a mixture of two or more selected from methanolamine, ethanolamine, propanolamine, butanolamine, diethanolamine, triethanolamine, dimethylethanolamine, and N-methylethanolamine, but is not limited thereto.

The etch stabilizer may be preferably added in an amount of 0.01 to 10% by weight, more preferably 0.05 to 7% by weight, and even more preferably 0.1 to 5% by weight, based on the total amount of the etching composition. Within the above range, the etch stabilizer can effectively suppress the generation of metal residues.

The glass etch inhibitor according to an embodiment of the present invention may be a mixture of one or more borofluoric acids or borofluoric acid salts. As a specific example, it may be any one or a mixture of two or more selected from HBF ₄ , NaBF ₄ , KBF ₄ and NH ₄ BF ₄ , but is not limited thereto.

The amount of the glass etching inhibitor may be preferably 0.01 to 10% by weight, more preferably 0.05 to 7% by weight, and even more preferably 0.1 to 5% by weight, based on the total amount of the etching composition. Within the above range, the effect of suppressing glass etching is excellent and the etching rate is not reduced, which may be preferable.

The etching composition according to an embodiment of the present invention may further include a glycol-based polymer, and may include polyethylene glycol as a specific example, but is not limited thereto. The glycol-based polymer according to an embodiment of the present invention may be added in an amount of 0.1 to 30% by weight, more preferably 1 to 20% by weight, and even more preferably 5 to 15% by weight, based on the total weight of the etching composition. This may be desirable. Within the above range, glycol-based polymers may be preferred because they have an excellent control effect on the hydrogen peroxide decomposition reaction and do not reduce etching ability.

The etching composition according to an embodiment of the present invention facilitates control of the etching speed when etching a metal or metal film, has an excellent etch profile, and has excellent straightness of wires. In addition, since residues can be completely removed, it can be very useful as an etching composition for transition metal films used for TFT-LCD gate and source/drain electrodes, especially films containing copper.

In addition, the etching composition according to an embodiment of the present invention is used in the etching process of a double metal film, especially a copper/molybdenum film or a copper/titanium film, and in addition to the above-mentioned advantages, it protects the interface of the metal film, suppresses interfacial overetching, and provides stability. This is excellent and can improve etching characteristics such as taper angle, CD loss, and visual straightness.

Accordingly, the etching composition according to an embodiment of the present invention uses a double metal film or a multi-metal film, especially a copper/molybdenum film, as a metal wiring material for the gate, source, or drain electrodes constituting the TFT (Thin Film Transistor) of the liquid crystal display device. In this case, it can be usefully used as an etching composition for forming a metal wiring pattern.

The etching composition according to an embodiment of the present invention is a composition that can be used for etching a metal film. The metal film described in the present invention means containing all metals, non-metals, or transition metals, and may preferably be a transition metal, and may be a metal or a transition metal. The transition metal may be included alone, or may be a metal or a mixed metal of transition metals.

Specifically, it may be a single metal film, a metal alloy film, or a metal oxide film, and examples of the metal oxide film include ITO, IZO, IGZO, etc.

Transition metals or metal films to which the etching composition according to an embodiment of the present invention can be applied include copper, molybdenum, titanium, indium, zinc, tin, tungsten, silver, gold, chromium, manganese, iron, cobalt, nickel, and niobium. It may be a film containing one or two or more selected metals or transition metals, and specific examples include a copper film, a copper/molybdenum film, a copper/titanium film, a copper/molybdenum alloy film, and a copper/indium alloy film, preferably copper. /It may be a molybdenum alloy film.

The copper/molybdenum film or copper/molybdenum alloy film according to an embodiment of the present invention is a multi-film in which one or more copper (Cu) films and one or more molybdenum (Mo) films and/or molybdenum alloy films (Mo-alloy) are stacked on each other. The multilayer may include a Cu/Mo(Mo-alloy) double layer, Cu/Mo(Mo-alloy)/Cu, or Mo(Mo-alloy)/Cu/Mo(alloy) triple layer. The order of the films can be appropriately adjusted depending on the material and adhesion of the substrate.

The molybdenum alloy film according to an embodiment of the present invention is molybdenum-tungsten (Mo-W), molybdenum-titanium (Mo-Ti), molybdenum-niobiumium (Mo-Nb), molybdenum It may be composed of denium-chromium (Mo-Cr) or molybdenum-tantalum (Mo-Ta), and the molybdenum film or molybdenum alloy film is 100 to 500 Å in terms of efficient etching without residue. The copper film can be deposited to have a thickness of 1000 to 10,000 Å.

Additionally, the present invention provides a method of etching a metal film including the step of etching the metal film by contacting the metal film with the etching composition of the present invention.

The method of etching a metal film using the etching composition of the present invention may be carried out according to a conventional method recognized by a person skilled in the art, except that the etching composition of the present invention is used.

Specifically, depositing a metal film on a substrate; Forming a photoresist film on the metal film and patterning it; And etching the metal film on which the patterned photoresist film is formed using the etching composition of the present invention, wherein the metal film formed on the substrate is a single film, a double metal film, or a multi-metal film. It may be a film (multilayer metal film), and in the case of a double metal film or multi-metal film, the stacking order is not particularly limited.

Additionally, the etching method may include forming a semiconductor structure between the substrate and the transition metal film, for example, in the case of a copper/molybdenum film, between the substrate and the copper film, or between the substrate and the molybdenum film.

The metal film of the metal film etching method according to an embodiment of the present invention may include one or two or more selected from copper, molybdenum, titanium, indium, zinc, tin, and niobium. As described above, the metal film is copper. A single metal film comprising; A copper alloy film including a copper alloy film; and a multilayer film comprising an upper film containing copper and a molybdenum film or a molybdenum alloy film, preferably comprising an upper film containing copper and a molybdenum film or a molybdenum alloy film. It can be a multi-act.

Additionally, the present invention provides a method for manufacturing a semiconductor device including an etching process performed using the etching composition of the present invention.

The semiconductor device according to an embodiment of the present invention 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 of a dielectric film, a conductive film, and an amorphous or polycrystalline silicon film, and these semiconductor structures can be manufactured according to conventional methods.

Hereinafter, the present invention will be described in detail by examples. However, the following examples are merely illustrative of the present invention and the content of the present invention is not limited to the following examples.

[Example 1]

Hydrogen peroxide 20% by weight, 5-aminotetrazole (ATZ) 0.5% by weight, iminodisuccinic acid (IDA) 3% by weight, ammonium fluoride (AF) 0.1% by weight, ingredients listed in Table 1 below, and An etching composition was prepared by mixing the remaining amount of water.

[Examples 2 to 6 and Comparative Examples 1 to 2]

An etching composition was prepared in the same manner as in Example 1, except that the components and contents shown in Table 1 below were different.

[Comparative Example 3]

An etching composition was prepared in the same manner as in Example 1, except that the components and contents shown in Table 1 below were different and a fluorine compound was not included.

[Comparative Example 4]

An etching composition was prepared in the same manner as in Example 1, except that the components and contents shown in Table 1 below were different and the amine compound was not included.

[Comparative Example 5]

An etching composition was prepared in the same manner as in Example 1, except that the components and contents shown in Table 1 below were different and the etching additive was not included.

[Comparative Examples 6 to 7]

An etching composition was prepared in the same manner as in Example 1, except that the components and contents of the etching additives shown in Table 1 below were different.

[Comparative Example 8]

Example 1 An etching composition was prepared in the same manner as in Example 1, except that the contents of the undercut inhibitor, etch additive, and amine compound shown in Table 1 below were changed and the pH adjuster was not added.

ingredient
(wt%) undercut inhibitor etch additive fluorine
compound Amine compound pH regulator water adenine guanine sulfuric acid AP AF HA NaOH Example 1 0.5 - 1.0 1.0 0.1 0.1 2 remaining amount Example 2 0.1 - 1.0 1.0 0.1 One 2 remaining amount Example 3 0.2 - 2.0 2.0 0.1 One One remaining amount Example 4 0.2 - 1.0 2.0 0.1 One One remaining amount Example 5 - 0.1 2.0 1.0 0.1 0.7 One remaining amount Example 6 - 0.1 0.5 0.5 0.1 0.5 One remaining amount Comparative Example 1 0.1 - 1.0 1.0 0.1 0.4 2 remaining amount Comparative Example 2 0.1 - 1.0 1.0 0.1 1.1 2 remaining amount Comparative Example 3 0.1 - 2.5 2.5 - 0.5 One remaining amount Comparative Example 4 0.1 - 0.5 1.5 0.1 - 2 remaining amount Comparative Example 5 0.1 - - - 0.1 0.5 2 remaining amount Comparative Example 6 0.1 - - 1.0 0.1 0.5 2 remaining amount Comparative Example 7 0.1 - 0.5 - 0.1 0.5 2 remaining amount Comparative example 8 0.1 - 2.0 2.0 0.1 0.5 - remaining amount

AP: ammonium hydrogen phosphate, HA: n-hexylamine

[Experimental Example 1] Etching characteristics evaluation

A specimen was manufactured by sequentially depositing a copper film and a molybdenum film each with a thickness of 4500 Å on a glass substrate. A photolithography process was performed on the specimen to form a patterned resist film, and the copper and molybdenum films were etched using the etching compositions of Examples 1 to 6 and Comparative Examples 1 to 5, respectively. At this time, the etching process was performed by adding 50% overetch to the EPD (end point detection) measured at 32°C using spray-capable equipment (Mini-etcher ME-001). EPD was measured by visually observing the color change of the specimen during etching, and the occurrence of undercut according to the taper angle, molybdenum residue, and number of treated sheets was observed using a scanning electron microscope (Hitachi, S-4800).

To determine whether etching heat was generated, the specimen was stored at a constant temperature of 32°C at a concentration of 7000 ppm, which is the limit for the etching solution, and the heat generation time was measured in the etchant.

If the temperature rises within 24 hours from the start of measurement and fever is observed, it is considered to be feverish. If the temperature does not rise for 24 hours, it is judged not to be feverish.

The results are shown in Table 2 below.

EPD(sec) Mo residue Whether you have a fever Undercut occurs Number of processed sheets Number of processed sheets Number of processed sheets Cu Mo 1000 5000 7000 Example 1 70 21 X X X X X Example 2 72 19 X X X X X Example 3 68 20 X X X X X Example 4 71 22 X X X X X Example 5 73 19 X X X X X Example 6 77 21 X X X X X Comparative Example 1 73 19 X O O O O Comparative Example 2 61 17 O X X X O Comparative Example 3 54 9 O X X X O Comparative Example 4 77 21 X O O O O Comparative Example 5 122 34 X O O O O Comparative Example 6 115 9 X O O O O Comparative Example 7 unetch Not measurable Not measurable Not measurable Not measurable Not measurable Comparative example 8 10 30 O X Not measured Not measured Not measured

As shown in Table 2, the etching compositions of Examples 1 to 6 of the present invention have very excellent etching speeds compared to the etching compositions of Comparative Examples 1 to 8, and no heat is generated during etching.

In addition, the etching composition of the present invention has excellent etching properties because no undercut occurs and no molybdenum residue remains even when the number of treated sheets increases.

This means that the etching composition of the present invention contains hydrogen peroxide; Etching additives that are phosphoric acid-based compounds and sulfuric acid-based compounds; pH adjuster; fluorine compounds; an undercut inhibitor that is adenine, guanine, or mixtures thereof; amine compounds; and the remaining amount of water.

Furthermore, in the case of Comparative Examples 1 to 2 where the weight ratio of the amine compound and the undercut inhibitor was outside the range of 5 to 10:1, problems such as residue and heat generation and undercut occurred, so the weight ratio of the amine compound and the undercut inhibitor was affected by the etching characteristics. It can be seen that it has a significant impact.

In addition, it can be seen that when the weight ratio of the etching additive and the PH regulator is in the range of 1 to 4:1, more improved etching characteristics are shown in terms of residue, heat generation, and undercutting.

Claims (12)

hydrogen peroxide; Etching additives that are phosphoric acid-based compounds and sulfuric acid-based compounds; pH adjuster; fluorine compounds; an undercut inhibitor that is adenine, guanine, or mixtures thereof; amine compounds; and a residual amount of water,
The composition includes 10 to 30% by weight of hydrogen peroxide, 0.01 to 5% by weight of an etching additive, and 0.1 to 3% by weight of a pH adjuster based on the total weight of the composition; An etching composition comprising 0.01 to 1% by weight of a fluorine compound, 0.01 to 2% by weight of an undercut inhibitor, 0.1 to 5% by weight of an amine compound, and a remaining amount of water. According to clause 1,
The amine compound is a C4 to C10 alkylamine, a C3 to C10 cycloalkylamine, or a mixture thereof. According to clause 1,
The etching composition wherein the undercut inhibitor and the amine compound have a weight ratio of 1:5 to 10. According to paragraph 1,
The etching composition wherein the pH regulator and the etching additive have a weight ratio of 1:1 to 4. According to clause 1,
The phosphoric acid-based compound is phosphoric acid, phosphate, or a mixture thereof, and the sulfuric acid-based compound is sulfuric acid, sulfate, or a mixture thereof. According to paragraph 1,
The etching composition wherein the fluorine compound is one or more selected from HF, NaF, KF, AlF3, HBF4, NH4F, NH4HF2, NaHF2, KHF2 and NH4BF4. According to clause 1,
The composition further includes one or two or more selected from the group of etching inhibitors and chelating agents. According to clause 6,
The etching inhibitor is a heterocyclic compound containing one or two or more heteroatoms selected from oxygen, sulfur, and nitrogen in the molecule, and the chelating agent is a compound containing an amino group, a carboxylic acid group, or a phosphonic acid group in the molecule. A method of etching a metal film comprising the step of etching the metal film by contacting the metal film with the etching composition of any one of claims 1 to 8. According to clause 9,
A method of etching a metal film, wherein the metal film includes one or two or more selected from copper, molybdenum, titanium, indium, zinc, tin, and niobium. According to clause 10,
The metal film may be a single metal film containing copper; A copper alloy film including a copper alloy film; and a method of etching a metal film selected from a multilayer comprising an upper film containing copper and a molybdenum film or a molybdenum alloy film. A method of manufacturing a semiconductor device comprising an etching process performed using the etching composition of any one of claims 1 to 8.