KR20210088950A - Etching solution for silicon nitride layer and method for preparing semiconductor device using the same - Google Patents

Abstract

The present invention relates to a silicon nitride etching solution and a method for manufacturing a semiconductor device using the same, and more specifically, to a silicon nitride etching solution and a method for manufacturing a semiconductor device performed using the same, wherein a silicon compound is not easily decomposed to prevent the generation of particles, and the silicon compound is easily decomposed under etching conditions to increase a selectivity for a silicon nitride film compared to a silicon oxide film.

Description

Silicon nitride etching solution and method of manufacturing a semiconductor device using the same

The present invention relates to a silicon nitride etching solution and a method for manufacturing a semiconductor device using the same, and more particularly, the silicon compound is not easily decomposed to prevent the generation of particles, and the silicon compound is easily decomposed under etching conditions, so that the silicon nitride film is easily decomposed compared to the silicon oxide film. The present invention relates to a silicon nitride film etching solution for increasing the selectivity for , and a method for manufacturing a semiconductor device using the same.

Currently, there are various methods for etching the silicon nitride layer, but the dry etching method and the wet etching method are mainly used.

The dry etching method is generally an etching method using a gas, and has the advantage that the isotropy is superior to the wet etching method. However, the wet etching method is widely used in that it is an expensive method and has lower productivity than the wet etching method.

In general, as a wet etching method, a method using phosphoric acid as an etching solution is well known. At this time, when only pure phosphoric acid is used to etch the silicon nitride film, as the device is miniaturized, not only the silicon nitride film but also the silicon oxide film are etched, so various defects and pattern abnormalities may occur. Therefore, a protective film on the silicon oxide film may occur. It is necessary to further lower the etching rate of the silicon oxide film by forming it.

An object of the present invention is to provide a silicon nitride etching solution that prevents generation of particles and increases the selectivity of the silicon nitride layer to the silicon oxide layer under etching conditions.

Another object of the present invention is to provide a method of manufacturing a semiconductor device performed using the above-described silicon nitride etching solution.

In order to solve the above-described technical problem, according to an aspect of the present invention, a silicon nitride layer etching solution includes an aqueous solution of phosphoric acid and at least one of compounds represented by Chemical Formulas 1 to 3 below.

[Formula 1]

[Formula 2]

[Formula 3]

In Formulas 1 to 3,

X _{1 To} X ₆ are each independently hydrogen, halogen, hydroxyl group, alkoxy group, amine group, C ₁ -C ₁₀ alkyl group, C ₃ -C ₁₀ cycloalkyl group, C ₁ -C ₁₀ alkylamino group, C ₂ -C _{30 It} is selected from a heteroaryl group containing nitrogen or sulfur and a C ₆ -C _{30 aryl group,}

R ₁ to R ₃ are each independently selected from hydrogen, an alkylamine group, an ether group, a C ₁ -C ₁₀ alkyl group, a C ₂ -C ₁₅ heteroaryl group containing nitrogen or sulfur, and a C ₆ -C ₁₅ aryl group do.

In addition, according to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device performed using the above-described silicon nitride etching solution.

The silicon nitride film etching solution according to the present invention may contain at least one of the compounds represented by Chemical Formulas 1 to 3 showing a stable silicon compound structure, thereby preventing growth as silicon-based particles.

In addition, the silicon nitride layer etching solution according to the present invention may include at least one of the compounds represented by Formulas 1 to 3, thereby increasing the etching selectivity for the silicon nitride layer compared to the silicon oxide layer.

1 is a cross-sectional view schematically illustrating a silicon nitride film removal process using an etching solution according to an embodiment of the present invention.

Advantages and features of the present invention and methods for achieving them will become apparent with reference to the following embodiments. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

Hereinafter, the silicon nitride etching solution according to the present invention will be described in detail.

In general, a silicon compound may be included in the silicon nitride etching solution to protect the silicon oxide layer from the aqueous phosphoric acid solution. However, a silane compound mainly used as a silicon compound has low solubility in an etching solution containing phosphoric acid. In order to increase the solubility of the silane compound in the etching solution, a silane compound in which a hydrophilic functional group is bonded to a silicon atom is used.

However, the hydrophilic functional group bonded to the silicon atom may be substituted with a hydroxyl group during etching or washing to form a silicon-hydroxy group (-Si-OH), and the silicon-hydroxy group may become a silicon atom and an oxygen atom by polymerization. A siloxane (-Si-O-Si-) group in which a random chain structure is formed by alternate bonding is generated.

As a result, the silane compound containing the siloxane group is grown and precipitated as silicon-based particles in which the siloxane group is repeatedly polymerized, and the silicon-based particles remain on the silicon substrate and cause defects in devices implemented on the substrate or are used in the etching or cleaning process. It remains in the equipment and acts as the biggest cause of equipment failure.

In order to prevent growth and precipitation of the silane compound as silicon-based particles, a silane compound in which an alkyl group or an aminoalkyl group is bonded to a silicon atom may be used. However, the compound is still not decomposed even under high-temperature etching conditions, so it is not possible to sufficiently form a passivation layer of the silicon oxide film, and thus the effect of increasing the etching selectivity for the silicon nitride film compared to the silicon oxide film is insufficient. will do

The silicon nitride film etching solution according to an embodiment of the present invention secures appropriate solubility, prevents growth as silicon-based particles, and is easily decomposed under etching conditions to increase the selectivity for the silicon nitride film compared to the silicon oxide film. At least one of the compounds represented by Formula 3 is included.

[Formula 1]

[Formula 2]

[Formula 3]

In Formulas 1 to 3,

X _{1 To} X ₆ are each independently hydrogen, halogen, hydroxyl group, alkoxy group, amine group, C ₁ -C ₁₀ alkyl group, C ₃ -C ₁₀ cycloalkyl group, C ₁ -C ₁₀ alkylamino group, C ₂ -C _{30 It} is selected from a heteroaryl group containing nitrogen or sulfur and a C ₆ -C _{30 aryl group,}

R ₁ to R ₃ are each independently selected from hydrogen, an alkylamine group, an ether group, a C ₁ -C ₁₀ alkyl group, a C ₂ -C ₁₅ heteroaryl group containing nitrogen or sulfur, and a C ₆ -C ₁₅ aryl group do.

In addition, according to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device performed using the above-described silicon nitride etching solution.

A C _a -C _b functional group herein refers to a functional group having a to b carbon atoms. For example, C _a -C _b alkyl refers to saturated aliphatic groups having a to b carbon atoms, including straight chain alkyl and branched alkyl and the like.

Specifically, alkyl is methyl, ethyl, n-propyl, i-propyl, n-butyl, s-butyl, i-butyl, t-butyl, pent-1-yl, pent-2-yl, pent-3-yl , 3-methylbut-1-yl, 3-methylbut-2-yl, 2-methylbut-2-yl, 2,2,2-trimethyleth-1-yl, n-hexyl, n-heptyl and n - May be octyl.

Also, cycloalkyl herein may be understood as the cyclic structure of alkyl. Non-limiting examples of cycloalkyl include cyclopentyl, cyclohexyl, 1-cyclohexenyl, 3-cyclohexenyl and cycloheptyl.

In addition, 　alkoxy herein refers to both an -O-(alkyl) group and an -O-(unsubstituted cycloalkyl) group, and is one or more ether groups and 1 to 10 carbon atoms. . Specifically, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexoxy, 1,2-dimethylbutoxy, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, and the like.

As used herein, unless otherwise specified, alkylamine refers to an amine substituted with a straight or branched alkyl group having 1 to 5 carbon atoms. Examples include, but are not limited to, methylamine, ethylamine, propylamine, butylamine, and the like.

In addition, the ether group herein means that an oxygen atom is connected by two alkyl groups or aryl groups.

As used herein, unless otherwise defined, aryl refers to an unsaturated aromatic ring comprising a single ring or multiple rings linked to each other by junctions or covalent bonds. Non-limiting examples of aryl include phenyl, biphenyl, o-terphenyl, m-terphenyl, p-terphenyl, 1-naphthyl, or 2-naphthyl.

As used herein, halogen means fluoro (-F), chloro (-Cl), bromo (-Br) or iodo (-I).

In Formulas 1 to 3, at least one functional group of _{X 1} to X _{6 bonded to a silicon atom preferably exhibits polarity.} For example, in Chemical Formulas 1 to 3, _{all of X 1} to X ₆ bonded to a silicon atom may represent a polarity as a hydroxyl group. The compounds represented by Formulas 1 to 3 _{may include a silicon atom to which a polar substituent of X 1} to X ₆ is bonded, thereby ensuring proper solubility of the silane compound in the etching solution.

For example, the compound represented by Formula 1 may be any one of compounds represented by the following compounds 1-1 to 1-6.

In addition, as an example, the compound represented by Formula 2 may be any one of compounds represented by the following compounds 2-1 to 2-6.

In addition, as an example, the compound represented by Formula 3 may be any one of compounds represented by the following compounds 3-1 to 3-6.

In particular, in the compounds represented by Chemical Formulas 1 to 3 of the present invention, by introducing a cyclo group to a silicon atom, growth and precipitation as silicon-based particles in which the siloxane group is repeatedly polymerized can be suppressed, and accordingly, to the silicon-based particles It is possible to prevent device failure and equipment failure.

More specifically, the cyclo group bonded to the silicon atom in the compounds represented by Chemical Formulas 1 to 3 shows a stable structure at room temperature. Due to this stable bonding structure, silicon atoms in the compounds represented by Formulas 1 to 3 are not substituted with Si-OH, which can prevent generation of siloxane groups in which silicon atoms and oxygen atoms are alternately bonded by Si-OH polymerization. have. That is, as the generation of siloxane groups in the silane compound is prevented, growth and precipitation as silicon-based particles may not occur. However, in the cyclo group in the compounds represented by Chemical Formulas 1 to 3, the hydrogen atom bonded to the carbon atom directly bonded to the silicon atom is not substituted with an alkyl, aryl or halogen group. When a hydrogen atom bonded to a carbon atom directly bonded to a silicon atom is substituted with alkyl or aryl, there may be a problem in that proper solubility of the silane compound in the etching solution cannot be secured. When a hydrogen atom bonded to a carbon atom directly bonded to a silicon atom is substituted with a halogen group, the stability of the bond may be lowered and the compounds represented by Chemical Formulas 1 to 3 may be decomposed. Accordingly, in the compounds represented by Chemical Formulas 1 to 3, a silicon atom may be substituted with Si-OH, and there may be a problem in that a siloxane group in which a silicon atom and an oxygen atom are alternately bonded to each other is generated by Si-OH polymerization.

The etching solution according to the present invention, including at least one of the compounds represented by Chemical Formulas 1 to 3, is decomposed under high-temperature etching conditions to sufficiently form a passivation layer of the silicon oxide film, and thus the silicon oxide film There is an effect of increasing the etch selectivity for the contrast silicon nitride layer. The high-temperature etching condition may be 60° C. or higher.

More specifically, the cyclo group bonded to the silicon atom in Chemical Formulas 1 to 3 is not decomposed in an environment other than a high-temperature etching condition, and thus does not grow as a silicon-based particle.

However, under high-temperature etching conditions, a cyclo group may be ring-opened in the compounds represented by Chemical Formulas 1 to 3 to form an alkene. Thereafter, the compound including the alkene structure reacts with the aqueous phosphoric acid solution to be substituted with Si-OH, and the Si-OH may form a strong hydrophilic interaction with the silicon oxide layer. As such, the compounds represented by Chemical Formulas 1 to 3 attached to the surface of the silicon oxide film through a strong hydrophilic interaction may serve to prevent etching from the phosphoric acid aqueous solution of the silicon oxide film.

It is preferable that the total content of the compounds represented by the above-described Chemical Formulas 1 to 3 is present in the silicon nitride etching solution in an amount of 100 to 100,000 ppm. In addition, it is more preferable that the total content of the compounds represented by the aforementioned Chemical Formulas 1 to 3 is present in the silicon nitride etching solution in an amount of 200 to 80,000 ppm. Here, the content of the additive is the amount of the compound represented by Chemical Formulas 1 to 3 dissolved in the silicon nitride film etching solution, and is expressed in units of ppm.

For example, the presence of 5,000 ppm of the compound represented by Chemical Formula 1 in the silicon nitride etching solution may mean that the compound represented by Chemical Formula 1 dissolved in the silicon nitride etching solution is 5,000 ppm.

When the total content of the compounds represented by Chemical Formulas 1 to 3 in the silicon nitride film etching solution is less than 100 ppm, the amount of the silicon compound is insufficient under the etching conditions, so the effect of increasing the etching selectivity for the silicon nitride film compared to the silicon oxide film is reduced. can be obscure

On the other hand, when the total content of the compounds represented by Chemical Formulas 1 to 3 in the silicon nitride etching solution exceeds 100,000 ppm, a problem in that the compound is not dissolved in the aqueous phosphoric acid solution may occur.

The silicon substrate may include a silicon nitride layer (Si _x N _y ) or a silicon oxide layer (SiO _x ) and a silicon nitride layer (Si _x N _y ) at the same time. Also. In the case of a silicon substrate including a silicon oxide layer and a silicon nitride layer at the same time, the silicon oxide layer and the silicon nitride layer may be alternately stacked or stacked in different regions.

The silicon oxide film is a SOD (Spin On Dielectric) film, HDP (High Density Plasma) film, thermal oxide film, BPSG (Borophosphate Silicate Glass) film, PSG (Phospho Silicate Glass) film, BSG depending on the use and type of material. (BoroSilicate Glass) film, PSZ (Polysilazane) film, FSG (Fluorinated Silicate Glass) film, LP-TEOS (Low Pressure TetraEthyl Ortho Silicate) film, PETEOS (Plasma Enhanced Tetra Ethyl Ortho Silicate) film, HTO (High Temperature Oxide) film MTO (Medium Temperature Oxide) film, USG (Undoped Silicate Glass) film, SOG (Spin On Glass) film, APL (Advanced Planarization Layer) film, ALD (Atomic Layer Deposition) film, PE-Oxide film (Plasma Enhanced oxide) or O ₃ -TEOS (O ₃ -Tetra Ethyl Ortho Silicate) and the like.

In one embodiment, the phosphoric acid aqueous solution is preferably included in an amount of 60 to 90 parts by weight based on 100 parts by weight of the silicon nitride etching solution.

When the content of the aqueous phosphoric acid solution is less than 60 parts by weight based on 100 parts by weight of the silicon nitride etching solution, the etching rate of the silicon nitride layer is lowered, so that the silicon nitride layer is not sufficiently etched or the process efficiency of the etching of the silicon nitride layer may be reduced.

On the other hand, when the content of the aqueous phosphoric acid solution exceeds 90 parts by weight with respect to 100 parts by weight of the silicon nitride etching solution, the increase in the etching rate of the silicon oxide film is large compared to the increase in the etching rate of the silicon nitride film, so the etching selection for the silicon nitride film compared to the silicon oxide film Rain may fall.

The silicon nitride layer etching solution according to an embodiment of the present invention compensates for the decrease in the etching rate of the silicon nitride layer due to the inclusion of at least one of the compounds represented by Formulas 1 to 3, and at the same time to improve the efficiency of the overall etching process. It may further comprise a fluorine-containing compound.

A fluorine-containing compound herein refers to any type of compound capable of dissociating fluorine ions.

In one embodiment, the fluorine-containing compound is at least one selected from hydrogen fluoride, ammonium fluoride, ammonium bifluoride and ammonium bifluoride.

Also, in another embodiment, the fluorine-containing compound may be a compound in which an organic cation and a fluorine-based anion are ionically bonded.

For example, the fluorine-containing compound may be a compound in which alkylammonium and a fluorine-based anion are ionically bonded. Here, the alkylammonium is ammonium having at least one alkyl group and may have up to four alkyl groups. The definition of the alkyl group has been described above.

In another example, the fluorine-containing compound is an alkylpyrrolium, alkylimidazolium, alkylpyrazolium, alkyloxazolium, alkylthiazolium, alkylpyridinium, alkylpyrimidinium, alkylpyridazinium, alkylpyra An organic cation selected from zinium, alkylpyrrolidinium, alkylphosphonium, alkylmorpholinium, dialkylimidazolium, and alkylpiperidinium and fluorophosphate, fluoroalkyl-fluorophosphate, fluoro The fluorine-based anion selected from borate and fluoroalkyl-fluoroborate may be an ionic liquid in an ion-bonded form.

Compared to hydrogen fluoride or ammonium fluoride, which are generally used as fluorine-containing compounds in the silicon nitride etching solution, the fluorine-containing compound provided in the form of an ionic liquid has a high boiling point and decomposition temperature, so it is decomposed during the etching process performed at high temperature Accordingly, there is an advantage in that there is little possibility of changing the composition of the etching solution.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device performed using the above-described silicon nitride etching solution.

According to the present manufacturing method, it is possible to manufacture a semiconductor device by performing a selective etching process on the silicon nitride layer using the above-described etching solution on a silicon substrate including at least a silicon nitride layer.

A silicon substrate used for manufacturing a semiconductor device may include a silicon nitride layer or may include a silicon oxide layer and a silicon nitride layer at the same time. Also. In the case of a silicon substrate including a silicon oxide layer and a silicon nitride layer at the same time, the silicon oxide layer and the silicon nitride layer may be alternately stacked or stacked in different regions.

The method of manufacturing a semiconductor device according to the present invention may be applied to a manufacturing process of a NAND device. More specifically, it may be performed by using the above-described etching solution in a process step requiring the selective removal of the silicon nitride film without loss of the silicon oxide film in the stacked structure for forming the NAND.

As an example, FIG. 1 is a schematic cross-sectional view for explaining a silicon nitride film removal process using an etching solution according to the present invention.

Referring to FIG. 1 , after forming a mask pattern layer 30 on a stack structure 20 in which a silicon nitride film 11 and a silicon oxide film 12 are alternately stacked on a silicon substrate 10 , an anisotropic etching process is performed. A trench 50 is formed through it.

In addition, referring to FIG. 1 , the etching solution according to the present invention is injected through the region of the trench 50 formed in the stack structure 20 , and accordingly, the silicon nitride layer 11 is etched, and the silicon oxide layer 12 and the mask. Only the pattern layer 30 remains.

That is, the present invention minimizes the etching of the silicon oxide film 12 in the stacked structure 20 by using an etching solution with an improved etch selectivity for the silicon nitride film compared to the silicon oxide film, and completely and selectively completes the silicon nitride film 11 for a sufficient time. can be removed with Thereafter, a semiconductor device may be manufactured through a subsequent process including forming a gate electrode in the region from which the silicon nitride layer 11 is removed.

Specific embodiments of the present invention are presented below. However, the examples described below are only for specifically illustrating or explaining the present invention, and the present invention is not limited thereto.

Example

etching Preparation of solution

In Examples 1 to 6, the compounds 1-1, 2-1, 3-1, 1-2, 2-3, and 3-4 were added to an aqueous solution of phosphoric acid to prepare an etching solution so that the initial concentration was 500 ppm.

The etching solution compositions according to Examples 1 to 6 are shown in Table 1.

Etching solution composition additive Example 1 Phosphoric acid aqueous solution
(85% by weight)
+
additive
(0.050% by weight)
+
remnant water compound 1-1 Example 2 compound 2-1 Example 3 compound 3-1 Example 4 compound 1-2 Example 5 compound 2-3 Example 6 compound 3-4

The etching solution compositions according to Comparative Examples 1 to 3 are shown in Table 2.

Etching solution composition additive Comparative Example 1 Phosphoric acid aqueous solution
(85% by weight)
+
remnant water - Comparative Example 2 Phosphoric acid aqueous solution (85 wt%)
+
additive
(0.050% by weight)
+
remnant water

Comparative Example 3 Phosphoric acid aqueous solution (85 wt%)
+
additive
(0.050% by weight)
+
remnant water

Experimental example

Silicon Oxide and Silicon of nitride film etching speed measurement

The silicon nitride etching solutions according to Examples 1 to 6 and Comparative Examples 1 to 3 were immersed in a heated etching solution at 165° C. for a 500 Å-thick silicon oxide layer and a silicon nitride layer and etched for 10 minutes.

The thickness of the silicon oxide film and the silicon nitride film before and after the etching was measured using an ellipsometer (Nano-View, SE MG-1000; Ellipsometery), and the etch rate was the difference in the thickness of the silicon oxide film and the silicon nitride film before and after the etching. It is a value calculated by dividing by the etching time (10 minutes).

The measured etch rates are shown in Table 3 below.

/min)silicon oxide film
etch rate (

/min) silicon nitride film
etch rate (

/min) etch selection
(Silicon nitride film etch rate / silicon oxide film etch rate) Example 1 0.15 96.55 643.67 Example 2 0.18 97.14 539.67 Example 3 0.16 95.99 599.94 Example 4 0.17 97.11 571.24 Example 5 0.18 97.12 539.56 Example 6 0.16 96.04 600.25 Comparative Example 1 5.56 96.73 17.40 Comparative Example 2 3.44 96.73 28.12 Comparative Example 3 4.01 96.30 24.01

As shown in Table 3, the etching solutions of Examples 1 to 6 can lower the etching rate for the silicon oxide film compared to the etching solutions of Comparative Examples 1 to 3, and accordingly, the etching selectivity for the silicon nitride film compared to the silicon oxide film is improvement can be seen.

silicone of particles Average diameter Measure

The average diameter of silicon-based particles present in the etching solutions of Examples 1 to 6 and Comparative Examples 2 and 3 over time at room temperature (25° C.) was measured. The average diameter of the silicon-based particles was measured using a particle size analyzer (PSA). The average diameters of the measured silicon-based particles are shown in Table 4 below.

time Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 comparative example
2 Comparative Example 3 Early <1nm <1nm <1nm <1nm <1nm <1nm 16nm 15nm after 4 hours <1nm <1nm <1nm <1nm <1nm <1nm 55nm 44nm after 12 hours <1nm <1nm <1nm <1nm <1nm <1nm 80nm 76nm after 24 hours <1nm <1nm <1nm <1nm <1nm <1nm >1μm >1μm

As shown in Table 4, it can be confirmed that the etching solutions of Examples 1 to 6 do not have silicon-based particles or have a diameter of less than 1 nm even if time elapses.

On the other hand, as shown in Table 4, it can be confirmed that silicon-based particles having a diameter of 1 μm or more are present in the etching solutions of Comparative Examples 2 and 3 over time.

In the above, although an embodiment of the present invention has been described, those of ordinary skill in the art can add, change, delete or add components within the scope that does not depart from the spirit of the present invention described in the claims. The present invention may be variously modified and changed by, etc., and this will also be included within the scope of the present invention.

10: silicon substrate 11: silicon nitride film
12: silicon oxide film 20: laminated structure
30: mask pattern layer 50: trench

Claims (9)

aqueous phosphoric acid solution; and
At least one of the compounds represented by Formula 1, Formula 2 and Formula 3 below; including
Silicon Nitride Etching Solution:
[Formula 1]

[Formula 2]

[Formula 3]

In Formulas 1 to 3,
X _{1 To} X ₆ are each independently hydrogen, halogen, hydroxyl group, alkoxy group, amine group, C ₁ -C ₁₀ alkyl group, C ₃ -C ₁₀ cycloalkyl group, C ₁ -C ₁₀ alkylamino group, C ₂ -C _{30 It} is selected from a heteroaryl group containing nitrogen or sulfur and a C ₆ -C _{30 aryl group,}
R ₁ to R ₃ are each independently selected from hydrogen, an alkylamine group, an ether group, a C ₁ -C ₁₀ alkyl group, a C ₂ -C ₁₅ heteroaryl group containing nitrogen or sulfur, and a C ₆ -C ₁₅ aryl group do.
According to claim 1,
In Formulas 1 to 3,
At least one of X ₁ to X ₆ is characterized in that it represents a polarity
Silicon nitride etching solution.
According to claim 1,
In Formulas 1 to 3,
X _{1 To} X ₆ is a hydroxyl group, characterized in that
Silicon nitride etching solution.
According to claim 1,
The total content of the compound represented by Chemical Formulas 1 to 3 in the silicon nitride etching solution is 100 to 100,000 ppm.
Silicon nitride etching solution.
According to claim 1,
The silicon nitride film etching solution further comprises at least one fluorine-containing compound selected from hydrogen fluoride, ammonium fluoride, ammonium bifluoride and ammonium hydrogen fluoride,
Silicon nitride etching solution.
According to claim 1,
The silicon nitride film etching solution further comprises a fluorine-containing compound having an ionic bond between an organic cation and a fluorine-based anion,
Silicon nitride etching solution.
7. The method of claim 6,
The organic cation is alkylimidazolium (Alkyl-imidazolium), dialkylimidazolium (DiAlkyl-imidazolium), alkylpyridinium (Alkyl-Pyridinium), alkylpyrrolidinium (Alkyl-pyrrolidinium), alkylphosphonium (Alkyl-phosphonium), characterized in that at least one selected from alkyl morpholinium (Alkyl-morpholinium) and alkyl piperidinium (Alkyl-piperidinium)
Silicon nitride etching solution.
7. The method of claim 6,
The fluorine-based anion is at least one selected from Fluorophosphate, Fluoroalkyl-fluorophosphate, Fluoroborate, and Fluoroalkyl-fluoroborate.
Silicon nitride etching solution.
A method of manufacturing a semiconductor device comprising an etching process performed using the silicon nitride layer etching solution according to claim 1 .

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