KR102240647B1 - Etching composion for silicon nitride layer - Google Patents

Abstract

The present invention is a silicon nitride film etching composition that minimizes the etch rate of a silicon oxide film, can selectively etch a silicon nitride film, does not leave particles on a substrate, and is stable at a high temperature.

Description

Silicon nitride film etching composition {ETCHING COMPOSION FOR SILICON NITRIDE LAYER}

The present invention is a silicon nitride film etching composition that minimizes the etch rate of a silicon oxide film, can selectively etch a silicon nitride film, does not leave particles on a substrate, and is stable at a high temperature.

A silicon oxide film (SiO2) and a silicon nitride film (SiNx) are used as representative insulating films used in a semiconductor manufacturing process, and may be used alone, or one or more silicon oxide films and one or more silicon nitride films may be alternately stacked. In addition, the silicon oxide film and the silicon nitride film are also used as a hard mask for forming a conductive pattern such as a metal wire.

Conventional wet etching process of silicon nitride film generally uses a mixture of phosphoric acid and deionized water at a high temperature of around 160℃, but silicon-based additives are added to prevent etching of the silicon oxide film due to phosphoric acid in the high temperature etching process. One etch composition has been proposed.

However, when the nitride layer is etched using an etching composition containing phosphoric acid, silicic acid, or silicate, the silicic acid or silicate causes particles that may affect the substrate, making it unsuitable for a semiconductor manufacturing process.

In Korean Patent Application Laid-Open Nos. 2011-0037741 and 2011-0037766, oxime silane and alkoxysilane compounds were added to phosphoric acid to control the etching rate of the silicon oxide film to 1 Å/min or less, and fluorine compound was added thereto to reduce the etch rate of the nitride film. It is disclosed that it was raised. However, conventional silane compounds have a problem in that a polymeric siloxane compound (Si-O-Si) is formed when contacted with water, and foreign matter adheres to the wafer surface, and the etching rate of the silicon nitride film and the oxide film is uniform due to the loss of the silicon compound. There is a problem that cannot be maintained.

As described above, due to the stability problem of silicon additives included in the conventional etching composition, particles are caused to cause many problems in the semiconductor manufacturing process.

Accordingly, there is a need for a high selectivity etchant for a silicon nitride layer capable of selectively etching the silicon nitride layer without damaging the silicon oxide layer while ensuring additive stability.

Korean Patent Publication No. 2011-0037741 Korean Patent Publication No. 2011-0037766 Korean Patent Publication No. 2014-0079267 Korean Patent Publication No. 2017-0001801

An object of the present invention is to provide a silicon nitride etching composition having a high selectivity that can selectively etch a silicon nitride layer while minimizing the etching of the silicon oxide layer, and does not have problems such as generation of particles that affect semiconductor device characteristics.

The present invention is phosphoric acid; And a silicon-based compound represented by Formula 1 below.

[Formula 1]

In Formula 1,

R ₁₁ to R ₁₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

이고;R ₁ to R ₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms, or

ego;

L ₁ , L, L ₁ ', and L'are each independently a C 1 to C 10 alkylene or a C 3 to C 8 cycloalkylene;

R ₂₁ to R ₂₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

a and b are each independently an integer of 0 to 20, provided that the sum of a and b is an integer of at least 1;

c is an integer from 0 to 20;

a', b'and c'are each independently an integer of 0 to 20;

m and n are each independently an integer of 0 to 5,

When m is an integer of 2 or more, L may be the same as or different _{from each other, and R 13} may be the same or different from each other,

When n is an integer of 2 or more, L'may be the same as or different from each other.

In the silicon nitride etching composition according to an embodiment of the present invention, the silicon-based compound may be at least one selected from silicon-based compounds represented by the following Chemical Formulas 2 to 4.

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4,

R ₁₁ to R ₁₄ are each independently hydrogen, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

이고;R ₁ to R ₃ are each independently halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, or

ego;

L ₁ , L ₂ and L ₃ are each independently an alkylene having 1 to 10 carbon atoms or a cycloalkylene having 3 to 8 carbon atoms;

a and b are each independently an integer of 0 to 20, provided that the sum of a and b is an integer of at least 1;

c and d are each independently an integer of 1 to 20;

L ₁ 'and L' are each independently C 1 -C 10 alkylene or C 3 -C 8 cycloalkylene, and a;

R ₂₁ to R ₂₃ are each independently hydrogen, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

a', b'and c'are each independently an integer of 0 to 20;

n is an integer from 0 to 2.

In the silicon nitride etching composition according to an embodiment of the present invention, R ₁₁ to R ₁₄ of the silicon-based compounds of Formulas 2 to 4 are each independently hydrogen or alkyl having 1 to 7 carbon atoms; R ₁ to R ₃ are each independently halogen, hydroxy or alkoxy having 1 to 7 carbon atoms; L ₁ , L ₂ and L ₃ are each independently a C 1 to C 7 alkylene or a C 5 to C 7 cycloalkylene; a and b are each independently an integer of 0 to 5, provided that the sum of a and b is an integer of at least 1; c and d may each independently be an integer of 1 to 5.

The silicon nitride etching composition according to an embodiment of the present invention may include 60 to 95% by weight of phosphoric acid and 0.01 to 3% by weight of a silicon-based compound based on the total weight of the silicon nitride etching composition.

In the silicon nitride layer etching composition according to an embodiment of the present invention, the silicon nitride layer/oxide layer etching selectivity may be 200 or more.

The silicon nitride etching composition according to an embodiment of the present invention may further include at least one additive selected from inorganic acids, organic acids, and ammonium salts.

In the silicon nitride etching composition according to an embodiment of the present invention, the inorganic acid may be at least one selected from the group consisting of hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, hydroperoxide, perchloric acid, and boric acid, as specific examples; The organic acids include formic acid, acetic acid, diacetic acid, iminodiacetic acid, methanesulfonic acid, ethanesulfonic acid, lactic acid, ascorbic acid, oxalic acid, propionic acid, butanoic acid, valeric acid, butyl acetic acid, enanthic acid, capric acid, tartaric acid, Succinic acid, malic acid, maleic acid, malonic acid, glycolic acid, gluconic acid, glycolic acid, glutaric acid, adipic acid, D-glucanoic acid, itaconic acid, citraconic acid, mesaconic acid, 2-oxoglutaric acid, tri It may be at least one selected from the group consisting of melitic acid, endotal, glutamic acid, methylsuccinic acid and citric acid; The ammonium salt is a specific example (NH ₄ ) ₂ SO ₄ , (NH ₄ ) ₃ PO ₄ , NH ₄ NO ₃ , NH ₄ CH ₃ CO ₂ , NH ₄ HCO ₃ , NH ₄ Cl, NH ₄ F, NH ₄ HF ₂ and NH ₄ BF _{4 It} may be at least one selected from the group consisting of.

The silicon nitride etching composition according to an embodiment of the present invention may further include at least one selected from surfactants, metal ion sequestering agents, antioxidants, and corrosion inhibitors.

In addition, the present invention provides a method of selectively etching a silicon nitride layer compared to a silicon oxide layer using the silicon nitride etching composition, and a method of manufacturing a semiconductor device including the etching method.

The silicon nitride film etching composition of the present invention suppresses the etching of the silicon oxide film, can etch the silicon nitride film with high selectivity, minimizes the damage of the silicon oxide film, effectively prevents the generation of particles, and prevents unwanted damage in the etching process. Because of this, it is possible to prevent the problem of deteriorating the characteristics of the manufactured device.

In addition, in the silicon nitride film etching composition of the present invention, at least one ethylene oxide (EO) repeating unit is bonded to a terminal nitrogen atom, and hydrogen is bonded to the terminal oxygen atom of the ethylene oxide repeating unit, or alkyl, cycloalkyl, or Al. Since it contains a stable silicon-based compound having a structure in which a hydrocarbon group such as kenyl is bonded, phosphoric acid heated to a high temperature does not etch the silicon oxide film due to the stability of the silicon-based compound in the etching process, while side reactions of the silicon-based compound Is prevented so that the silicon nitride layer can be selectively etched without generation of particles. Accordingly, the silicon nitride film etching composition according to the present invention can improve device characteristics by selectively etching the nitride film while preventing the oxide film from being damaged or from deteriorating electrical properties due to etching of the oxide film and particle generation when the nitride film is etched.

In addition, the silicon nitride etching composition of the present invention has excellent storage stability, and can maintain a stable etching rate and high etching selectivity for the silicon nitride layer even after repeated etching processes.

Hereinafter, the present invention will be described in more detail. If there are no other definitions in the technical terms and scientific terms used at this time, they have the meanings commonly understood by those of ordinary skill in the technical field to which this invention belongs, and the following description will unnecessarily obscure the subject matter of the present invention. Description of possible known functions and configurations will be omitted.

As used herein, the term “etch selectivity (E _SiNx / E _SiO2 )” refers to the ratio of the etching rate (E _SiNx ) of the silicon nitride layer to the etching rate (E _{SiO2) of the silicon oxide layer.} In addition, when the etching rate of the silicon oxide layer is close to zero or the value of the etching selectivity is large, it means that the silicon nitride layer can be selectively etched.

In the present specification, the term "change of the etch selectivity" refers to an absolute value of the difference between the initial etch selectivity and the etch selectivity when the etching process is repeatedly performed two or more times using the same etching composition.

In the present specification, the term “etch rate drift (ΔERD)” refers to a rate of change in the etch rate compared to the initial etch rate when the etching process is repeatedly performed two or more times using the same etching composition. Specifically, the etch rate reduction rate △ERD is calculated as △ERD(%) = [1-{(Etching speed when used more than n times) / (Etching speed when used once)}]×100, where n is a natural number of 2 or more. to be. In general, it is defined as a decrease rate as the tendency of the etching ability, that is, the etching rate to decrease as the etching process is repeatedly performed, and the rate of change is also interpreted as the same meaning.

The term "halogen" in the present specification means a fluorine, chlorine, bromine or iodine atom.

The term “alkyl” in the present specification refers to a linear or branched saturated hydrocarbon monovalent group consisting of only carbon and hydrogen atoms, specifically methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, hexyl, Octyl, nonyl, and the like, but are not limited thereto.

In the present specification, the term “alkoxy” refers to a monovalent group in which oxygen and alkyl are bonded, wherein “alkyl” is as defined above. Examples of such alkoxy include, but are not limited to, methoxy, ethoxy, isopropoxy, butoxy, isobutoxy, t-butoxy, and the like.

As used herein, the term “alkenyl” refers to a linear or branched unsaturated hydrocarbon monovalent group containing one or more double bonds between two or more carbon atoms, specifically ethenyl, propenyl, prop-1- En-2yl, 1-butenyl, 2-butenyl, isobutylenyl, 1-pentenyl, 2-pentenyl, 3-methyl-1-butenyl, 2-methyl-2-butenyl, 2,3 -Dimethyl-2-butenyl, and the like, but are not limited thereto.

The term “cycloalkyl” in the present specification refers to a saturated carbocyclic monovalent group composed of one or more rings, and specifically includes, but is not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like. Does not.

The term “alkylene” in the present specification refers to a straight chain or branched saturated hydrocarbon divalent group consisting of only carbon and hydrogen atoms, specifically methylene, ethylene, propylene, isopropylene, butylene, isobutylene, t-butylene, Pentylene, hexylene, octylene, nonylene, and the like, but are not limited thereto.

The term “cycloalkylene” in the present specification refers to a saturated carbocyclic divalent group composed of one or more rings, and specifically includes cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene, etc. , But is not limited thereto.

The present invention is phosphoric acid; And a silicon-based compound represented by Formula 1 below, wherein the silicon-based compound is a component capable of inhibiting etching of silicon oxide.

[Formula 1]

In Formula 1,

R ₁₁ to R ₁₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

이고;R ₁ to R ₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms, or

ego;

L ₁ , L, L ₁ ', and L'are each independently a C 1 to C 10 alkylene or a C 3 to C 8 cycloalkylene;

R ₂₁ to R ₂₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

a and b are each independently an integer of 0 to 20, provided that the sum of a and b is an integer of at least 1;

c is an integer from 0 to 20;

a', b'and c'are each independently an integer of 0 to 20;

m and n are each independently an integer of 0 to 5,

When m is an integer of 2 or more, L may be the same as or different _{from each other, and R 13} may be the same or different from each other,

When n is an integer of 2 or more, L'may be the same as or different from each other.

The silicon-based compound of Formula 1 has a structure in which at least one ethylene oxide repeating unit is bonded to a terminal nitrogen atom, and hydrogen is bonded to a terminal oxygen atom of the ethylene oxide repeating unit, or a hydrocarbon group such as alkyl, cycloalkyl, or alkenyl is bonded. It is characterized by a structured structure. The silicon-based compound of Formula 1 has excellent solubility in water by increasing hydrogen bonding with water due to the ethylene oxide repeating unit bonded to the nitrogen atom in the molecule, and is a hydrocarbon bonded to the terminal oxygen atom of the ethylene oxide repeating unit. Due to the group, side reactions of the silicon-based compound are prevented during the high-temperature etching process. Due to the stability of the silicon-based compound, phosphoric acid heated to a high temperature during the etching process is inhibited from etching the silicon oxide layer, and at the same time, the generation of particles by preventing side reactions is prevented, so that the silicon nitride layer can be selectively etched without defects in the substrate. do.

The silicon-based compound according to an embodiment of the present invention may be at least one selected from the silicon-based compounds represented by Chemical Formulas 2 to 4, preferably in terms of preventing the etching of the silicon oxide layer.

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4,

R ₁₁ to R ₁₄ are each independently hydrogen, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

이고;R ₁ to R ₃ are each independently halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, or

ego;

L ₁ , L ₂ and L ₃ are each independently an alkylene having 1 to 10 carbon atoms or a cycloalkylene having 3 to 8 carbon atoms;

a and b are each independently an integer of 0 to 20, provided that the sum of a and b is an integer of at least 1;

c and d are each independently an integer of 1 to 20;

L ₁ 'and L' are each independently C 1 -C 10 alkylene or C 3 -C 8 cycloalkylene, and a;

R ₂₁ to R ₂₃ are each independently hydrogen, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;

a', b'and c'are each independently an integer of 0 to 20;

n is an integer from 0 to 2.

In the silicon-based compound according to an embodiment of the present invention, more preferably, R ₁₁ to R ₁₄ in Formulas 2 to 4 are each independently hydrogen or alkyl having 1 to 7 carbon atoms; R ₁ to R ₃ are each independently halogen, hydroxy or alkoxy having 1 to 7 carbon atoms; L ₁ , L ₂ and L ₃ are each independently a C 1 to C 7 alkylene or a C 5 to C 7 cycloalkylene; a and b are each independently an integer of 0 to 5, provided that the sum of a and b is an integer of at least 1; c and d may each independently be at least one selected from silicon-based compounds that are integers of 1 to 5.

In the silicon-based compound according to an embodiment of the present invention, in Formulas 2 to 4, R ₁₁ to R ₁₄ are each independently hydrogen or alkyl having 1 to 4 carbon atoms; R ₁ to R ₃ are each independently halogen, hydroxy or alkoxy having 1 to 4 carbon atoms; L ₁ , L ₂ and L ₃ are each independently an alkylene having 2 to 5 carbon atoms or a cycloalkylene having 5 to 6 carbon atoms; a and b are each independently an integer of 0 to 5, provided that the sum of a and b is an integer of at least 1; c and d may each independently be at least one selected from silicon-based compounds that are integers of 1 to 5.

In the silicon-based compound according to an embodiment of the present invention, even more preferably, each of R ₁₁ to R ₁₄ is independently hydrogen, methyl, ethyl, propyl or butyl; R ₁ to R ₃ are each independently chloro, hydroxy, methoxy, ethoxy or butoxy; L ₁ , L ₂ and L ₃ are each independently ethylene, propylene, butylene, pentylene, hexylene, cyclopentylene or cyclohexylene; a and b are each independently an integer of 0 to 5, provided that the sum of a and b is an integer of at least 1; c and d may each independently be at least one selected from silicon-based compounds that are integers of 1 to 5.

The silicon-based compound according to an embodiment of the present invention may specifically be at least one silicon-based compound selected from the following structures, but is not limited thereto.

Phosphoric acid contained in the silicon nitride film etching composition according to an embodiment of the present invention provides hydrogen ions in the composition and serves to etch the silicon nitride film by maintaining high temperature processing conditions.

The silicon nitride film etching composition of the present invention may contain a residual amount of water, and the water is not particularly limited, and is preferably deionized water, and more preferably, deionized water for semiconductor processing having a resistivity of 18㏁·cm or more. It is good.

The content of phosphoric acid, a silicon-based compound, and water constituting the silicon nitride film etching composition according to an embodiment of the present invention is not particularly limited, but phosphoric acid 60 to 95% by weight based on the total weight of the silicon nitride film etching composition, silicon-based compound 0.01 It is preferable to include to 3% by weight and the balance of water. Within the above range, while maintaining high temperature stability during the semiconductor etching process, a high silicon oxide layer/nitride layer selectivity and an improved silicon nitride layer etching rate may be realized, and the formation of particles may be effectively suppressed.

In the case where the phosphoric acid content is less than 60% by weight in the silicon nitride layer etching composition of the present invention, the silicon nitride layer etching rate is lowered, so that the nitride layer may not be easily removed, and when the phosphoric acid content exceeds 95% by weight, the silicon oxide layer is etched. As the speed increases, the silicon nitride/oxide selection ratio may be reduced.

More preferably, the silicon nitride layer etching composition according to an embodiment of the present invention may include 70 to 90% by weight of phosphoric acid, 0.05 to 1% by weight of the silicon-based compound, and the balance of water based on the total weight of the silicon nitride layer etching composition. In such a range, stability in a high-temperature etching process is maintained, and the silicon oxide layer etching rate is effectively reduced, thereby effectively improving the silicon nitride layer/oxide layer selectivity and preventing the generation of particles. In addition, the etching rate for the silicon oxide layer and the silicon nitride layer can be kept constant despite the repeated etching process.

Particularly preferably, the silicon nitride layer etching composition according to an embodiment of the present invention may include 75 to 85% by weight of phosphoric acid, 0.05 to 0.5% by weight of a silicon-based compound, and the balance of water based on the total weight of the silicon nitride layer etching composition. In this range, stability in the etching process at a high temperature of 140°C or higher is maintained, completely suppressing the generation of particles, and remarkably reducing the silicon oxide film etch rate, thereby realizing a very high silicon nitride/oxide selection ratio, and repetitive etching. Even after the process, it is possible to maintain a stable etching rate and high etching selectivity for the silicon nitride layer.

In addition, the silicon nitride etching composition according to an embodiment of the present invention may further include at least one additive selected from inorganic acids, organic acids, and ammonium salts as needed for pH adjustment, and any one known in the art may be used without limitation. I can. The content of the additive is not particularly limited, but may be further included in an amount of 0.01 to 10% by weight based on the total weight of the silicon nitride film etching composition.

In a specific example, the inorganic acid may be at least one selected from the group consisting of hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, hydroperic acid, perchloric acid, and boric acid; The organic acids are formic acid, acetic acid, diacetic acid, iminodiacetic acid, methanesulfonic acid, ethanesulfonic acid, lactic acid, ascorbic acid, oxalic acid, propionic acid, butanoic acid, valeric acid, butylacetic acid, enanthic acid, capric acid, tartaric acid, succinic acid, malic acid. , Maleic acid, malonic acid, glycolic acid, gluconic acid, glycoic acid, glutaric acid, adipic acid, D-glucanoic acid, itaconic acid, citraconic acid, mesaconic acid, 2-oxoglutaric acid, trimellitic acid, It may be at least one selected from the group consisting of endotal, glutamic acid, methylsuccinic acid and citric acid; The ammonium salt is (NH ₄ ) ₂ SO ₄ , (NH ₄ ) ₃ PO ₄ , NH ₄ NO ₃ , NH ₄ CH ₃ CO ₂ , NH ₄ HCO ₃ , NH ₄ Cl, NH ₄ F, NH ₄ HF ₂ and NH _It may be at least one selected from the group consisting of 4 BF _4.

In addition, the silicon nitride film etching composition according to an embodiment of the present invention may further include optional additives commonly used in the art to improve etching performance, and the optional additives include surfactants, antioxidants, Corrosion inhibitors, etc. can be used.

The surfactant is used to remove the etched residue, and can be used without limitation as long as it is dissolved in the silicon nitride film etching composition of the present invention. For example, anionic surfactant, cationic surfactant, or nonionic surfactant may be used. Can be used. Examples of the cationic surfactant include _{amines such as C 8} H ₁₇ NH ₂ , and examples of the anionic surfactant include _{hydrocarbon-based carboxylic acids such as C 8} H ₁₇ COOH, and hydrocarbon-based such as C ₈ H ₁₇ SO ₃ H. Fluorine-based carboxylic acids such as sulfonic acid and H(CF ₂ ) ₆ COOH, and other nonionic surfactants include ethers such as polyoxyalkylene alkyl ether. The surfactant may be further included in an amount of 0.0005 to 5% by weight based on the total weight of the silicon nitride etching composition.

The antioxidants and corrosion inhibitors are used to prevent corrosion of metals or metal compounds used as semiconductor device materials during the etching process, and the antioxidants and corrosion inhibitors can be used without limitation as long as they are used in the industry. At least one selected from compounds consisting of azole compounds, amine compounds, acid compounds, and polyhydric alcohol compounds can be used.

Examples of the azole compounds include 5-aminotetrazole, 5-methyl-1H-tetrazole, 1H-tetrazole-5-acetic acid, imidazole, 2-methylimidazole, 1-(3-aminopropyl)-imidazole , Histidine, 4-methylimidazole, 1,2,3-triazole, 1,2,4-triazole, pyrazole, pyridine, pyrimidine, pyrrole, pyrrolidone, pyrroline, benzotriazole, benzo Triazole-5-carboxylic acid, 5-methyl-1H-benzotriazole, indole, purine, 2-aminobenzimidazole, adenine, guanine, tolutriazole, 4-methyl-1H-benzotriazole, 1H -Benzotriazole-1-methanol, etc. can be illustrated. Examples of the amine compounds include p-phenylenediamine, polyaniline, aniline, N-phenyl-p-phenylenediamine, tyramine, triamine hydrochloride, hexamethylenetetramine, urea, dibutylamine, piperazine, 1-(2- Hydroxyethyl) piperazine, 2-methyl piperazine, triethylamine, 2-dimethylaminoethanol, etc. can be illustrated. Examples of the acid compounds include glycine, nicotinic acid, sodium gluconate, valine, glutamic acid, aspartic acid, ascorbic acid, nitrobenzene, and picric acid. D-sorbitol etc. can be illustrated as said polyhydric alcohol compound. The antioxidant and corrosion inhibitor may be further included in an amount of 0.01 to 10% by weight based on the total weight of the silicon nitride etching composition.

When etching is performed on a semiconductor wafer using the silicon nitride etching composition according to an embodiment of the present invention, the etching rate of the silicon nitride layer of the silicon nitride layer etching composition is 50 to 80 Å/min, and the etching rate of the silicon oxide layer is It may be 0 to 0.4 Å/min, and the silicon nitride/oxide etching selectivity (E _SiNx / E _SiO2 ) may be 200 or more, preferably ∞. In particular, when the silicon nitride layer is selectively etched while the etching rate of the silicon oxide layer is almost zero, the silicon nitride layer/oxide layer selection ratio may be ∞.

When the silicon nitride film etching composition of the present invention is mixed with the silicon nitride film and the silicon oxide film, since the silicon nitride film is selectively and rapidly etched without affecting the etching of the silicon oxide film, a high silicon nitride film/oxide film selectivity is achieved in the semiconductor process. Can be implemented.

In addition, the silicon nitride film etching composition of the present invention implements high-temperature stability due to the silicon-based compound to prevent side reactions by inhibiting phosphoric acid heated to a high temperature from etching the silicon oxide film, thereby preventing the occurrence of foreign substances, thereby preventing substrate failure. In addition, the etching rate of the silicon nitride layer may be maintained, and excellent semiconductor device characteristics may be implemented.

The silicon nitride etching composition of the present invention effectively suppresses the generation of particles and can selectively etch the silicon nitride layer with excellent stability even during a high-temperature semiconductor etching process, and stable etching speed and etching selectivity for the silicon nitride layer even after repeated etching processes. Can be given.

The present invention provides a method of selectively etching a silicon nitride layer compared to a silicon oxide layer by using the etching composition. In this case, the etching method may be performed according to a method commonly used in the art.

According to the etching method according to an embodiment of the present invention, the silicon nitride layer is etched faster than the silicon oxide layer, thereby selectively etching the silicon nitride layer, and since particles are not formed during the etching process, the silicon nitride layer is more stable. The nitride film can be etched. In addition, it is possible to effectively prevent the silicon oxide film from being unnecessarily removed or damaged.

In the present invention, a silicon nitride film is a concept including a SiN, SiON, and doped SiN film, and refers to a film quality that is widely used as an insulating film when forming a gate electrode or the like.

In addition, the silicon oxide film is not limited as long as it is a silicon oxide film commonly used in the art, but as an example, a spin on dielectric (SOD) film, a high density plasma (HDP) film, a thermal oxide film, a BPSG (Borophosphate Silicate Glass) ) Film, PSG (Phospho Silicate Glass) film, BSG (Boro Silicate Glass) film, PSZ (Polysilazane) film, FSG (Fluorinated Silicate Glass) film, LPTEOS (Low Pressure Tetra Ethyl Ortho Silicate) film, PETEOS (Plasma Enhanced Tetra Ethyl) film Ortho Silicate) film, HTO (High Temperature Oxide) film, MTO (Medium Temperature Oxide) film, USG (Undopped Silicate Glass) film, SOG (Spin On Glass) film, APL (Advanced Planarization Layer) film, ALD (Atomic Layer Deposition) ) Film, PE-oxide film (Plasma Enhanced Oxide), O3-TEOS (O3-Tetra Ethyl Ortho Silicate) film, and a combination thereof.

In this case, the silicon oxide film or silicon nitride film may be formed in various thicknesses depending on the purpose. For example, the silicon oxide layer or the silicon nitride layer may be independently formed to a thickness of 100 to 3,000 Å, but is not limited thereto.

In addition, the process of selectively etching the nitride layer using the silicon nitride layer etching composition of the present invention may be performed according to a method known in the art, and examples include a method of immersion and a method of spraying. During the etching process, the process temperature may be 100° C. or higher, preferably in the range of 100 to 500° C., more preferably in the range of 100 to 300° C., and the appropriate temperature may be changed as necessary in consideration of other processes and other factors. I can.

In addition, the present invention is the phosphoric acid; And at least one of the silicon-based compounds represented by Chemical Formula 1; and an etching process performed using a silicon nitride film etching composition including.

The kind of the semiconductor device is not particularly limited in the present invention.

The etching process is characterized in that the silicon nitride layer is selectively etched with respect to the silicon oxide layer without causing a particle problem.

According to the method of manufacturing a semiconductor device according to an embodiment of the present invention, when a silicon nitride layer and a silicon oxide layer are alternately stacked or mixed, selective etching of the silicon nitride layer is possible, and by effectively suppressing damage to the silicon oxide layer, etching Minimizes the damage to the silicon oxide film by In addition, it is possible to secure the stability and reliability of the process by completely preventing the generation of particles, which have been a problem in the conventional etching process.

Therefore, the etching method according to the present invention can selectively remove the silicon nitride layer compared to the silicon oxide layer, effectively prevent particle generation, and maintain the etching rate and the etching selectivity constant despite repeated etching processes. Since the generation of particles can be completely prevented, it can be efficiently applied to various processes that require selective etching of the silicon nitride layer with respect to the silicon oxide layer.

Hereinafter, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[Preparation Example 1] Silicon-based compound Si-1 [In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,3-propylene, a=1, b=0, R ₁₁ =R ₁₂ = Production of [corresponding to hydrogen]

To a flask equipped with a cooling tube and a stirrer, triethoxysilane (100 parts by weight) was added, and 2-(allylamino)ethanol (2-(allylamino)ethanol) was added to triethoxy silane in a molar ratio of 1:1. Then, ethyl acetate (500 parts by weight) was added as a solvent. The reaction mixture was heated to 50° C., and then Karstedt's catalyst (0.004 parts by weight) was added thereto, followed by hydrosilylation at 80° C. for 3 hours to obtain compound Si-1.

¹ H-NMR (500 MHz, CDCl ₃ ): δ 0.67 (t, 2H), 1.26 (t, 9H), 1.57 (m, 2H), 2.2 (Br, 2H), 2.55 (m, 2H), 2.74 ( m, 2H), 3.68 (m, 2H), 3.84 (m, 6H)

[Production Examples 2 to 9] Preparation of silicon-based compounds Si-2 to Si-9

Silicon-based compounds Si-2 to Si-9 were prepared in a similar manner to Preparation Example 1, and the structures of the silicon-based compounds Si-2 to Si-9 are as follows.

Silicon-based compound Si-2: (EtO) ₃ Si-CH ₂ CH ₂ CH ₂ -N[CH ₂ CH ₂ OH] ₂ [In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1, 3-propylene, a=b=1, R ₁₁ =R ₁₂ =corresponds to hydrogen]

Silicon compound Si-3: (HO) ₃ Si-CH ₂ CH ₂ CH ₂ -N[CH ₂ CH ₂ OH] ₂ [In Formula 2, R ₁ =R ₂ =R ₃ =hydroxy, L ₁ =1, 3-propylene, a=b=1, R ₁₁ =R ₁₂ =corresponds to hydrogen]

Silicon compound Si-4: (Cl) ₃ Si-CH ₂ CH ₂ CH ₂ -N[CH ₂ CH ₂ OH] ₂ [In Formula 2, R ₁ =R ₂ =R ₃ =chloro, L ₁ =1,3 -Propylene, a=b=1, R ₁₁ =R ₁₂ =corresponds to hydrogen]

Silicon compound Si-5: (EtO) ₃ Si-CH ₂ CH ₂ CH ₂ -N(CH ₂ CH ₂ OH)-CH ₂ CH ₂ CH ₂ -N[CH ₂ CH ₂ OH] ₂ [R in Formula 3 ₁ =R ₂ =R ₃ =ethoxy, L ₁ =L ₂ =1,3-propylene, a=b=c=1, R ₁₁ =R ₁₂ =R ₁₃ =corresponds to hydrogen]]

Silicon compound Si-6: (EtO) ₃ Si-CH ₂ CH ₂ CH ₂ -N(CH ₂ CH ₂ OH)-CH ₂ CH ₂ CH ₂ -N(CH ₂ CH ₂ OH)-CH ₂ CH ₂ CH ₂ -N[CH ₂ CH ₂ OH] ₂ [In Formula 4, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =L ₂ =L ₃ =1,3-propylene, a=b=c=d= 1, R ₁₁ =R ₁₂ =R ₁₃ =R ₁₄ =corresponds to hydrogen]

Silicon compound Si-7: (EtO) ₃ Si-CH ₂ CH ₂ -NHCH ₂ CH ₂ OCH ₃ [In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,2-ethylene, a =1, b=0, R ₁₁ =methyl, R ₁₂ =corresponds to hydrogen]

Silicon compound Si-8: (EtO) ₃ Si-CH ₂ CH ₂ CH ₂ -N((CH ₂ CH ₂ O) ₅ H)-CH ₂ CH ₂ CH ₂ -N[(CH ₂ CH ₂ O) ₅ H] ₂ [In Formula 3, R ₁ =R ₂ =R ₃ = ethoxy, L ₁ =L ₂ =1,3-propylene, a=b=c=5, R ₁₁ =R ₁₂ =R ₁₃ =hydrogen Applicable]

Silicon compound Si-9: (EtO) ₃ Si-CH ₂ CH ₂ CH ₂ -N[(CH ₂ CH ₂ O) ₅ CH ₃ ] ₂ [In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,3-propylene, a=b=5, R ₁₁ =R ₁₂ =corresponds to methyl]

[Examples 1 to 10 and Comparative Examples 1 to 6] Preparation of silicon nitride film etching composition

After mixing at the composition ratio shown in Table 1 below, the mixture was stirred at room temperature for 5 minutes at a speed of 500 rpm to prepare a silicon nitride film etching composition. The content of water was taken as the remaining amount so that the total weight of the composition was 100% by weight.

division Phosphoric acid (wt%) Silicon compound Other ingredients water
(wt%) ingredient Content (wt%) ingredient Content (wt%) Example 1 85 Si-1 0.5 - - Balance Example 2 85 Si-1 0.1 - - Balance Example 3 85 Si-2 0.5 - - Balance Example 4 85 Si-3 0.5 - - Balance Example 5 85 Si-4 0.5 - - Balance Example 6 85 Si-5 0.5 - - Balance Example 7 85 Si-6 0.5 - - Balance Example 8 85 Si-7 0.5 - - Balance Example 9 85 Si-8 0.5 - - Balance Example 10 85 Si-9 0.5 - - Balance Comparative Example 1 85 - - - - Balance Comparative Example 2 85 - - HF 0.05 Balance Comparative Example 3 85 - - AC One Balance Comparative Example 4 85 APTES 0.5 - - Balance Comparative Example 5 85 HPST 0.5 - - Balance Comparative Example 6 85 THSPS 0.1 - - Balance Si-1: In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,3-propylene, a=1, b=0, R ₁₁ =R ₁₂ =hydrogen silicon-based compound
Si-2: In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,3-propylene, a=b=1, R ₁₁ =R ₁₂ =hydrogen silicon-based compound
Si-3: In Chemical Formula 2, R ₁ =R ₂ =R ₃ =hydroxy, L ₁ =1,3-propylene, a=b=1, R ₁₁ =R ₁₂ =hydrogen silicon-based compound
Si-4: In Chemical Formula 2, R ₁ =R ₂ =R ₃ =chloro, L ₁ =1,3-propylene, a=b=1, R ₁₁ =R ₁₂ =hydrogen silicon-based compound
Si-5: In Formula 3, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =L ₂ =1,3-propylene, a=b=c=1, R ₁₁ =R ₁₂ =R ₁₃ =hydrogen Phosphorus silicon compound
Si-6: In Formula 4, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =L ₂ =L ₃ =1,3-propylene, a=b=c=d=1, R ₁₁ =R ₁₂ =R ₁₃ =R ₁₄ =Silicon compound which is hydrogen
Si-7: In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,2-ethylene, a=1, b=0, R ₁₁ =methyl, R ₁₂ =hydrogen silicon-based compound
Si-8: In Formula 3, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =L ₂ =1,3-propylene, a=b=c=5, R ₁₁ =R ₁₂ =R ₁₃ =hydrogen Phosphorus silicon compound
Si-9: In Formula 2, R ₁ =R ₂ =R ₃ =ethoxy, L ₁ =1,3-propylene, a=b=5, R ₁₁ =R ₁₂ =methyl silicon-based compound
HF: Hydrofluoric acid
AC: NH ₄ Cl (Ammonium chloride)
APTES: 3-Aminopropyl triethoxysilane
HPST: (3-hydroxypropyl)silane triol
THSPS: 3-(trihydroxysilyl)propane-1-sulfonic acid (3-(trihydroxysilyl)propane-1-sulfonic acid)

[Experimental Example 1] Measurement of etching amount and etching rate of silicon nitride film and silicon oxide film

In order to investigate the etching performance of the silicon nitride etching compositions prepared in the above Examples and Comparative Examples, a silicon nitride film (SiN film) wafer and a silicon oxide film (thermal oxide film) were deposited by depositing in the same manner as in the semiconductor manufacturing process using a CVD method. ) Or LP-TEOS (Low Pressure Tetra Ethyl Ortho Silicate) film) wafers were prepared, respectively.

Before starting the etching, the thickness before etching was measured using an ellipsometer (Ellipsometer, J.A WOOLLAM, M-2000U), which is a thin film thickness measuring device. The etching process was performed by immersing the wafer in a silicon nitride film etchant (Examples 1 to 10 and Comparative Examples 1 to 6) maintained at an etching temperature of 157° C. in a quartz bath for 10 minutes each. After the etching was completed, it was washed with ultrapure water, and the remaining etchant and moisture were completely dried using a drying device.

The etching rate was calculated by dividing the difference between the thickness before etching and the thickness after etching using an ellipsometer (Ellipsometer, J.A WOOLLAM, M-2000U) by the etching time (minutes), and the results are shown in Table 2 below.

[Experimental Example 2] Evaluation of selective etching of silicon nitride layer on silicon oxide layer

The etch selectivity (the etch rate of the silicon nitride film/the etch rate of the silicon oxide film) was calculated by the ratio of the etch rate of the silicon nitride film and the etch rate of the silicon oxide film, and is shown in Table 2 below.

[Experimental Example 3] Evaluation of particle generation degree

The surfaces of the silicon oxide films etched in Examples 1 to 10 and Comparative Examples 1 to 6 were measured with an electron scanning microscope (SEM) to examine whether particles were generated, and are shown in Table 2 below.

Etching process
Temperature
(℃) Nitride film
Etching rate
(Å/min) Oxide film etch rate
(Å/min) Selection ratio particle
Occur
Whether ThOx ^* LP-TEOS ^** Nitride film
/ThOx Nitride film
/LP-TEOS Example 1 157 60.2 0 0.25 ∞ 240.8 X Example 2 157 60.9 0 0.24 ∞ 253.8 X Example 3 157 60.7 0 0.23 ∞ 263.9 X Example 4 157 60.3 0 0.24 ∞ 251.3 X Example 5 157 61.3 0.11 0.27 557.3 227.0 X Example 6 157 57.1 0 0.22 ∞ 259.5 X Example 7 157 56.5 0 0.21 ∞ 269.0 X Example 8 157 61.3 0.05 0.24 1226 255.4 X Example 9 157 59.1 0 0.22 ∞ 268.6 X Example 10 157 61.5 0 0.21 ∞ 292.9 X Comparative Example 1 157 63.2 1.6 13.4 39.5 4.7 O Comparative Example 2 157 77.4 6.0 33.8 12.9 2.3 O Comparative Example 3 157 66.3 1.5 13.6 44.2 4.9 X Comparative Example 4 157 58.1 0 0.22 ∞ 264.1 O Comparative Example 5 157 54.2 0.21 - 258.1 - O Comparative Example 6 157 52.3 0.2 - 261.5 - O ^* ThOx: Thermal oxide
^** LP-TEOS: Low Pressure Tetra Ethyl Ortho Silicate Film

As shown in Table 2, the silicon nitride film etching compositions of Examples 1 to 10 exhibited excellent etching rates for the silicon nitride films and at the same time exhibited a low etching rate regardless of the type of silicon oxide film, resulting in excellent etching selectivity. In addition, particle generation was effectively prevented.

However, the silicon nitride etching compositions of Comparative Examples 1 and 2 remarkably deteriorated the silicon oxide etching inhibitory power, and as a result, showed a low etch selectivity as well as particles were generated, making it unsuitable for selectively and stably etching the silicon nitride layer. In addition, the silicon nitride film etching composition of Comparative Example 3 did not generate particles during the etching process, but the etching selectivity for the silicon nitride film was very low, and thus it was unsuitable for selectively etching the silicon nitride film. In addition, although the silicon nitride etching compositions of Comparative Examples 4 to 6 exhibited a high etch selectivity, particles were generated due to side reactions during the etching process, and thus were not suitable for stably etching the silicon nitride layer.

That is, the silicon nitride etching compositions of Examples 1 to 10 significantly reduced the etching rate of the silicon oxide layer compared to the silicon nitride etching compositions of Comparative Examples 1 to 3 that do not contain a silicon-based compound. Accordingly, it was found that when the silicon-based compound of Formula 1 was included in the silicon nitride layer etching composition, etching of the silicon oxide layer was remarkably suppressed, and the etching selectivity of the silicon nitride layer to the silicon oxide layer was remarkably increased.

In addition, in the silicon nitride film etching compositions of Examples 1 to 10, at least one ethylene oxide repeating unit is bonded to a terminal nitrogen atom, hydrogen is bonded to a terminal oxygen atom of the ethylene oxide repeating unit, or a hydrocarbon group such as alkyl is bonded. Since it contains a sub-compound, the generation of particles generated during the etching process was effectively prevented compared to Comparative Examples 4 to 6 each containing APTES, HPST, and THSPS.

That is, since the silicon-based compound of Formula 1 included in the silicon nitride film etching composition of the present invention is very stable under high-temperature acid conditions, phosphoric acid heated to a high temperature during the etching process effectively inhibits etching the silicon oxide film. By preventing the occurrence of side reactions, the generation of particles, which has been a problem in the past, can be completely prevented, so that the silicon nitride film can be highly selectively etched without defects in the substrate, and stability and reliability of the process can be secured.

Accordingly, the silicon nitride film etching composition according to the present invention can improve device characteristics by selectively etching the nitride film while preventing the oxide film from being damaged or from deteriorating electrical properties due to etching of the oxide film and particle generation when the nitride film is etched.

The present invention is not limited by the above-described embodiments and the accompanying drawings, and it is common in the technical field to which the present invention pertains that various substitutions, modifications, and changes are possible within the scope of the technical spirit of the present invention. It will be obvious to those who have knowledge.

Claims (10)

Phosphoric acid; And
A silicon-based compound represented by the following formula (1); Silicon nitride film etching composition comprising.
[Formula 1]

In Formula 1,
R ₁₁ to R ₁₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;
R ₁ to R ₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, alkenyl having 2 to 10 carbon atoms, or

ego;
L ₁ , L, L ₁ 'and L'are each independently a C 1 to C 10 alkylene or a C 3 to C 8 cycloalkylene;
R ₂₁ to R ₂₃ are each independently hydrogen, halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;
a and b are each independently an integer of 0 to 20, provided that the sum of a and b is an integer of at least 1;
c is an integer from 0 to 20;
a', b'and c'are each independently an integer of 0 to 20;
m and n are each independently an integer of 0 to 5,
When m is an integer of 2 or more, L may be the same as or different _{from each other, and R 13} may be the same or different from each other,
When n is an integer of 2 or more, L'may be the same as or different from each other. The method of claim 1,
The silicon-based compound is at least one selected from silicon-based compounds represented by Chemical Formula 2, Chemical Formula 3, and Chemical Formula 4 below.
[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 2 to 4,
R ₁₁ to R ₁₄ are each independently hydrogen, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;
R ₁ to R ₃ are each independently halogen, hydroxy, alkoxy having 1 to 10 carbon atoms, or

ego;
L ₁ , L ₂ and L ₃ are each independently an alkylene having 1 to 10 carbon atoms or a cycloalkylene having 3 to 8 carbon atoms;
a and b are each independently an integer of 0 to 20, provided that the sum of a and b is an integer of at least 1;
c and d are each independently an integer of 1 to 20;
L ₁ 'and L' are each independently C 1 -C 10 alkylene or C 3 -C 8 cycloalkylene, and a;
R ₂₁ to R ₂₃ are each independently hydrogen, alkyl having 1 to 10 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, or alkenyl having 2 to 10 carbon atoms;
a', b'and c'are each independently an integer of 0 to 20;
n is an integer from 0 to 2. The method of claim 2,
Each of R ₁₁ to R ₁₄ is independently hydrogen or alkyl having 1 to 7 carbon atoms; R ₁ to R ₃ are each independently halogen, hydroxy or alkoxy having 1 to 7 carbon atoms; L ₁ , L ₂ and L ₃ are each independently a C 1 to C 7 alkylene or a C 5 to C 7 cycloalkylene; a and b are each independently an integer of 0 to 5, provided that the sum of a and b is an integer of at least 1; c and d are each independently an integer of 1 to 5, a silicon nitride film etching composition. The method of claim 1,
The silicon nitride layer etching composition includes 60 to 95% by weight of phosphoric acid and 0.01 to 3% by weight of a silicon-based compound based on the total weight of the silicon nitride layer etching composition. The method of claim 1,
The silicon nitride layer etching composition has a silicon nitride layer/oxide layer etching selection ratio of 200 or more. The method of claim 1,
The silicon nitride layer etching composition further comprises at least one additive selected from inorganic acids, organic acids, and ammonium salts. The method of claim 6,
The inorganic acid is at least one selected from the group consisting of hydrofluoric acid, hydrochloric acid, sulfuric acid, nitric acid, hydroperoxide, perchloric acid and boric acid; The organic acids are formic acid, acetic acid, diacetic acid, iminodiacetic acid, methanesulfonic acid, ethanesulfonic acid, lactic acid, ascorbic acid, oxalic acid, propionic acid, butanoic acid, valeric acid, butylacetic acid, enanthic acid, capric acid, tartaric acid, succinic acid, malic acid. , Maleic acid, malonic acid, glycolic acid, gluconic acid, glycoic acid, glutaric acid, adipic acid, D-glucanoic acid, itaconic acid, citraconic acid, mesaconic acid, 2-oxoglutaric acid, trimellitic acid, At least one selected from the group consisting of endotal, glutamic acid, methylsuccinic acid and citric acid; The ammonium salt is (NH ₄ ) ₂ SO ₄ , (NH ₄ ) ₃ PO ₄ , NH ₄ NO ₃ , NH ₄ CH ₃ CO ₂ , NH ₄ HCO ₃ , NH ₄ Cl, NH ₄ F, NH ₄ HF ₂ and NH At least one selected from the group consisting of ₄ BF _{4, a silicon nitride film etching composition.} The method of claim 1,
The silicon nitride layer etching composition further comprises at least one selected from surfactants, antioxidants, and corrosion inhibitors. A method of selectively etching a silicon nitride layer compared to a silicon oxide layer by using the silicon nitride layer etching composition according to any one of claims 1 to 8. A method of manufacturing a semiconductor device including an etching process performed using the silicon nitride etching composition of any one of claims 1 to 8.