Etching solution composition

Abstract

Provided is an etching solution composition capable of preventing reduction in the etching rate of a silicon nitride film, achieving high etching selectivity with respect to silicon nitride, and suppressing deposition of silica on the surface of silicon oxide.　This etching solution composition is based on an inorganic acid and is for selectively etching silicon nitride from a semiconductor containing the silicon nitride and silicon oxide, and comprises: (a) a fluorine compound that increases the etching rate of silicon nitride; and (b) a volatilization inhibitor that inhibits volatilization of the fluorine compound.

Description

Etching solution composition

[0001] The present invention relates to an inorganic acid-based etchant composition for selectively etching silicon nitride from semiconductors containing silicon nitride and silicon oxide.

[0002]

[0003] With the recent trend toward higher integration and higher capacity of semiconductor circuits, there is a demand for more precise etching techniques. For example, in the manufacture of NAND flash memories (3D NAND) having a three-dimensional structure, a three-dimensional structure in which silicon nitride films and silicon oxide films are alternately stacked is treated using an etching solution, but in this case, it is required to selectively treat only the silicon nitride film. To date, various etching solution compositions have been developed for the purpose of advanced etching treatment.

[0003] For example, Patent Document 1 discloses a silicon nitride etching composition used in the manufacturing process of 3D NAND, which contains phosphoric acid, a specific silane compound, a solvent containing water, and optionally a fluorine compound, and is said to have an advantageously high etching rate for silicon nitride films and advantageously high selectivity for silicon nitride over silicon oxide.

[0004] Furthermore, as described in Patent Document 2, there is an etching solution containing a mixture of phosphoric acid, tetrafluoroboric acid, a silicon compound, water, and at least one of sulfuric acid and an ionic liquid. It is disclosed that the silicon compound functions as a selectivity enhancer, the tetrafluoroboric acid functions as an etchant for silicon nitride, and has the effect of increasing the etching rate of silicon nitride while also increasing the oxide film rate, and that decomposition of tetrafluoroboric acid is suppressed compared to hydrofluoric acid.

[0005] Patent Document 3 discloses that in etching a silicon nitride film, a silicon fluoride compound is removed together with evaporating water, and indicates that the use of hydrogen fluoride in a phosphoric acid-based etching solution composition increases the difficulty of process control in long-term semiconductor processes.

[0006] JP 2023-109854 A JP 2020-161626 A JP 07-086260 A

[0007] It is known that silicon nitride processing in semiconductor processes takes a long time (at least one hour or more), and adding a small amount of hydrogen fluoride increases the silicon nitride film deposition rate and shortens the processing time, but at the same time increases the oxide film deposition rate, reducing the etching selectivity of the silicon nitride film. Such a decrease in selectivity can cause semiconductor manufacturing defects, and the volatilization of fluorine compounds due to long etching times also reduces the etching rate of the silicon nitride film, making the semiconductor process more unstable.

[0008] Patent Documents 1 and 2 disclose etching compositions that can obtain a high silicon nitride film formation rate while maintaining high selectivity to silicon nitride, but do not recognize or take into consideration the fact that fluorine compounds are removed by silicon compounds derived from the silicon nitride film, which reduces the silicon nitride film formation rate, as described in Patent Document 3.

[0009] Furthermore, when silicon nitride is etched with an etching solution composition containing phosphoric acid and water, ammonium phosphate [(NH ４ ) ３ P.O. ４ ))] and silicic acid [SiO ｘ (OH) ４―２ｘ ] ｎ When the concentration of silicic acid in the liquid increases, these undergo dehydration condensation to form silica [SiO ｘ This deposit can cause defects such as short circuits and wiring failures in semiconductor products, and must therefore be eliminated as much as possible.

[0010] Therefore, with conventional etching solution compositions, it is not easy to suppress the deposition of silica on the surface of silicon oxide while maintaining a high selectivity and increasing the etching rate of silicon nitride, and there is still room for improvement.

[0011] The present invention has been made in view of the above problems, and an object of the present invention is to provide an etching solution composition that can prevent a decrease in the etching rate of a silicon nitride film, achieve high etching selectivity for silicon nitride, and suppress the deposition of silica on the surface of silicon oxide.

[0012] The etching solution composition according to the present invention, which solves the above-mentioned problems, is characterized by the following: it is an inorganic acid-based etching solution composition for selectively etching silicon nitride from a semiconductor containing silicon nitride and silicon oxide, and contains: (a) a fluorine compound that increases the etching rate of silicon nitride; and (b) a volatilization inhibitor that suppresses the volatilization of the fluorine compound.

[0013] According to the etching solution composition of the present invention, the etching rate of silicon nitride is increased by the fluorine compound, while the volatilization inhibitor suppresses the volatilization of the fluorine compound. Therefore, even if the Si concentration in the etching solution composition increases, the etching rate of silicon nitride is maintained at a high level, and the etching process can be carried out stably.

[0014] In the etching liquid composition according to the present invention, the fluorine compound preferably includes an ionic compound whose counter anion is fluorine.

[0015] According to the etching solution composition of the present invention, by selecting the above-mentioned suitable ionic compound as the fluorine compound, the etching rate of silicon nitride can be further increased.

[0016] In the etching solution composition according to the present invention, the fluorine compound preferably includes at least one selected from the group consisting of ammonium hexafluorophosphate, tetrafluoroboric acid, 1-ethyl-3-methylimidazolium hexafluorophosphate, tetramethylammonium hexafluorophosphate, tetraethylphosphonium hexafluorophosphate, and 1-butyl-1-methylpyrrolidinium hexafluorophosphate.

[0017] According to the etching solution composition of the present invention, by selecting the above specific compound as the fluorine compound, the etching rate of silicon nitride can be further increased.

[0018] In the etching solution composition according to the present invention, the volatilization inhibitor preferably includes a compound or salt having at least one skeleton selected from the group consisting of an imidazolium skeleton, a pyrrolidinium skeleton, a piperidinium skeleton, a morphonium skeleton, a pyridinium skeleton, a quaternary phosphonium skeleton, and a quaternary ammonium skeleton, and does not contain a fluorine atom.

[0019] According to the etching solution composition of the present invention, the volatilization of the fluorine compound can be further suppressed by selecting the above-mentioned suitable compounds or salts as the volatilization inhibitor.

[0020] In the etching solution composition according to the present invention, the volatilization inhibitor is preferably imidazole, tetrabutylphosphonium bromide, tetrakis(hydroxymethyl)phosphonium sulfate, tetrabutylammonium bromide, or 1-ethyl-1-methylpyrrolidinium bromide.

[0021] According to the etching solution composition of the present invention, the volatilization of the fluorine compound can be further suppressed by selecting the above-mentioned specific compounds or salts as the volatilization inhibitor.

[0022] The etching liquid composition according to the present invention preferably further contains: (c) an etching inhibitor that inhibits etching of silicon oxide; and (d) a deposition inhibitor that inhibits deposition of silica on the surface of silicon oxide.

[0023] According to the etching solution composition of this configuration, the etching inhibitor inhibits silicon oxide from being etched by water, while silicon nitride is etched primarily by inorganic acid, thereby improving etching selectivity for silicon nitride in semiconductors containing silicon nitride and silicon oxide. Furthermore, the precipitation inhibitor inhibits silica deposition on the silicon oxide surface, thereby preventing defects such as short circuits and wiring defects in semiconductor products. Furthermore, the use of such an etching solution composition allows for etching treatment with excellent etching selectivity and high throughput.

[0024] In the etching solution composition according to the present invention, the etching inhibitor preferably comprises a first etching inhibitor having, in its molecular structure, three or less alkoxy groups, hydroxyl groups, and / or functional groups that can be precursors of hydroxyl groups, and a second etching inhibitor having, in its molecular structure, four or more alkoxy groups, hydroxyl groups, and / or functional groups that can be precursors of hydroxyl groups.

[0025] With the etching solution composition of this configuration, when silicon nitride is not etched, the concentration of Si in the solution is low, which raises concerns that the etching rate for silicon oxide will be high. However, by using an etching inhibitor that contains a first etching inhibitor having, in its molecular structure, three or fewer alkoxy groups, hydroxyl groups, and / or functional groups that serve as precursors to hydroxyl groups, and a second etching inhibitor having, in its molecular structure, four or more alkoxy groups, hydroxyl groups, and / or functional groups that serve as precursors to hydroxyl groups, etching of silicon oxide can be continuously suppressed, and etching selectivity for silicon nitride can be maintained over a long period of time, regardless of the concentration of Si in the solution.

[0026] In the etching liquid composition according to the present invention, the first etching inhibitor is preferably a silane compound having an amino group.

[0027] According to the etching solution composition of the present invention, by selecting a silane compound having an amino group as the first etching inhibitor, it is possible to achieve both the effect of the etching inhibitor in inhibiting etching of silicon oxide and the effect of the precipitation inhibitor in inhibiting precipitation of silica on the surface of silicon oxide, thereby improving etching selectivity for silicon nitride.

[0028] In the etching liquid composition according to the present invention, the silane compound having an amino group preferably includes 3-aminopropyltrimethoxysilane and / or 3-aminopropyltriethoxysilane.

[0029] According to the etching solution composition of the present invention, since the etching inhibitor contains the above-mentioned specific compound as the first etching inhibitor, it is possible to achieve both the effect of the etching inhibitor in inhibiting etching of silicon oxide and the effect of the precipitation inhibitor in inhibiting precipitation of silica on the surface of silicon oxide, thereby further improving the etching selectivity for silicon nitride.

[0030] In the etching solution composition according to the present invention, the second etching inhibitor is represented by the following formula (I):

[0031] Preferably, the compound has the chemical structure shown in the following formula (I): １ ~R ６ are substituents, at least four of which are at least one specific substituent selected from the group consisting of an alkoxy group, a hydroxyl group, and a halogen group, and the substituents other than the specific substituents are at least one substituent selected from the group consisting of an alkyl group, an aryl group, a carbonyl group, a carboxyl group, an amino group, an ethylenediamine group, and derivatives or composite groups of these substituents. X in formula (I) is "O" (oxygen atom) or "-" (single bond). n in formula (I) is an integer of 0 to 6.

[0032] According to the etching solution composition of the present invention, since the etching inhibitor contains the above-described suitable compound as the second etching inhibitor, it is possible to achieve both the effect of the etching inhibitor in inhibiting etching of silicon oxide and the effect of the precipitation inhibitor in inhibiting precipitation of silica on the surface of silicon oxide, thereby further improving the etching selectivity for silicon nitride.

[0033] In the etching liquid composition according to the present invention, the second etching inhibitor is represented by the following formula (2):

[0034] It is preferable that the compound has the chemical structure shown below.

[0035] According to the etching solution composition of the present invention, since the etching inhibitor contains the above-described suitable compound as the second etching inhibitor, it is possible to achieve both the effect of the etching inhibitor in inhibiting etching of silicon oxide and the effect of the precipitation inhibitor in inhibiting precipitation of silica on the surface of silicon oxide, thereby further improving the etching selectivity for silicon nitride.

[0036] In the etching solution composition according to the present invention, the precipitation inhibitor preferably contains a hydrazide.

[0037] According to the etching solution composition of the present invention, by selecting a hydrazide as the deposition inhibitor, an excellent effect of inhibiting the deposition of silica on the surface of silicon oxide can be obtained.

[0038] In the etching solution composition according to the present invention, the hydrazides preferably include at least one selected from the group consisting of adipic acid dihydrazide, succinic acid dihydrazide, and azelaic acid dihydrazide.

[0039] According to the etching solution composition of the present invention, since the specific compound described above is contained as a deposition inhibitor, an even more excellent effect of inhibiting silica deposition on the surface of silicon oxide can be obtained.

[0040] An embodiment of the etching liquid composition according to the present invention will be described below, however, it is not intended that the present invention be limited to the following embodiment.

[0041] [Etching Solution Composition] The etching solution composition according to the present invention is used to selectively etch silicon nitride from a semiconductor containing silicon nitride and silicon oxide. Each component contained in the etching solution composition will be described below.

[0042] <Inorganic Acid> The etching solution composition according to the present invention is based on an inorganic acid. Examples of inorganic acids include phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, and mixed acids of these inorganic acids. Of these inorganic acids, phosphoric acid is preferred. When used after dilution, phosphoric acid is in the form of an aqueous solution, and the concentration is preferably 50 to 100 wt %, more preferably 70 to 98 wt %, and even more preferably 80 to 95 wt %. The phosphoric acid may be adjusted to the above concentration when the etching solution composition is used. For example, a stock solution containing a low-concentration aqueous phosphoric acid solution may be concentrated at or before use, a stock solution containing phosphoric acid (strong phosphoric acid) with a concentration exceeding 100 wt % may be diluted with water at or before use, or phosphoric anhydride (P ２ O ５ ) can be dissolved in water at the time of use or before use to adjust to the above appropriate concentration.

[0043] <Fluorine Compound> The etching solution composition according to the present invention contains a fluorine compound that improves the etching rate of silicon nitride. The content of the fluorine compound in the etching solution composition is preferably 0.001 to 1.0 wt %, more preferably 0.01 to 0.5 wt %. The fluorine compound is preferably an ionic compound. In this case, examples of the counter cation include an imidazolium skeleton, a pyrrolidinium skeleton, a piperidinium skeleton, a morphonium skeleton, a pyridinium skeleton, a quaternary phosphonium skeleton, a quaternary ammonium skeleton, and a sulfonium skeleton, and examples of the counter anion include BF ４ － , P.F. ６ － , (CF ３ SO ２ ) N － , (F ２ SO ２ ) N － , C.F. ３ COO － , and CF ３ SO３ － The above ionic compounds may be used alone or in a mixture of two or more. A particularly preferred ionic compound is BF ４ － is the anion tetrafluoroborate, PF ６ － In addition to the above, compounds such as ammonium hexafluorophosphate and tetrafluoroboric acid can be mentioned.

[0044] [Fluorine Compound Having an Imidazole Skeleton] Examples of fluorine compounds having an imidazole skeleton include 1,3-dimethylimidazolium hexafluorophosphate, 1-methyl-3-propylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-methyl-2,3-dimethylimidazolium hexafluorophosphate, 1-ethyl-2,3-dimethylimidazolium hexafluorophosphate, 1-butyl-2,3-dimethylimidazolium hexafluorophosphate, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1-methyl-3-octylimidazolium hexafluorophosphate, and 1-ethyl-3-octylimidazolium hexafluorophosphate. Examples of the imidazolium salts include phosphoric acid, 1-butyl-3-octylimidazolium hexafluorophosphate, 1,3-dimethylimidazolium tetrafluoroborate, 1-methyl-3-propylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-methyl-3-octylimidazolium tetrafluoroborate, 1-ethyl-3-octylimidazolium tetrafluoroborate, and 1-butyl-3-octylimidazolium tetrafluoroborate. The above-mentioned fluorine compounds having an imidazole skeleton may be used alone or in a mixture of two or more.

[0045] [Fluorine Compound Having a Pyrrolidine Skeleton] Examples of fluorine compounds having a pyrrolidine skeleton include 1-methyl-1-methylpyrrolidinium hexafluorophosphate, 1-ethyl-1-methylpyrrolidinium hexafluorophosphate, 1-butyl-1-methylpyrrolidinium hexafluorophosphate, 1-methyl-1-propylpyrrolidin-1-ium hexafluorophosphate, 1-ethyl-1-propylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-propylpyrrolidin-1-ium hexafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-ethyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-ethyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-methyl ... Examples of the fluorine compound having a pyrrolidine skeleton include pyrrolidinium salts such as 1-ium hexafluorophosphate, 1-ethyl-1-methylpyrrolidinium tetrafluoroborate, 1-butyl-1-methylpyrrolidinium tetrafluoroborate, 1-methyl-1-propylpyrrolidin-1-ium tetrafluoroborate, 1-ethyl-1-propylpyrrolidin-1-ium tetrafluorophosphate, 1-butyl-1-propylpyrrolidin-1-ium tetrafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium tetrafluoroborate, 1-ethyl-1-octylpyrrolidin-1-ium tetrafluorophosphate, and 1-butyl-1-octylpyrrolidin-1-ium tetrafluoroborate. The fluorine compounds having a pyrrolidine skeleton may be used alone or in a mixture of two or more.

[0046] [Fluorine Compound Having a Piperidine Skeleton] Examples of the compound having a piperidine skeleton include piperidinium salts such as 1,1-dimethylpiperidinium hexafluorophosphate, 1-methyl-1-propylpiperidinium hexafluorophosphate, 1-ethyl-1-propylpiperidinium hexafluorophosphate, 1-butyl-1-methylpiperidinium hexafluorophosphate, 1,1-dimethylpiperidinium tetrafluoroborate, 1-methyl-1-propylpiperidinium tetrafluoroborate, 1-ethyl-1-methylpiperidinium tetrafluoroborate, 1-butyl-1-methylpiperidinium tetrafluoroborate, (piperidinium-1-ylmethyl)trifluoroborate, 1-(cyanomethyl)piperidinium tetrafluoroborate, 1-butyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, and 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide. The above-mentioned fluorine compounds having a piperidine skeleton may be used alone or in a mixture of two or more kinds.

[0047] [Fluorine Compound Having a Morpholine Skeleton] Examples of compounds having a morpholine skeleton include morphonium salts such as 4-methyl-4-methylmorpholinium hexafluorophosphate, 4-ethyl-4-methylmorpholinium hexafluorophosphate, 4-methyl-4-methylmorpholinium tetrafluoroborate, and 4-ethyl-4-methylmorpholinium tetrafluoroborate. The above fluorine compounds having a morpholine skeleton may be used alone or in a mixture of two or more. 4-(2-ethoxyethyl)-4-methylmorpholinium bisimide may also be used.

[0048] [Fluorine Compound Having a Pyridine Skeleton] Examples of fluorine compounds having a pyridine skeleton include 1-methylpyridinium hexafluorophosphate, 1-ethylpyridinium hexafluorophosphate, 1-butylpyridinium hexafluorophosphate, 1-octylpyridinium hexafluorophosphate, 1-acetonylpyridinium hexafluorophosphate, 1-methyl-3-methylpyridinium hexafluorophosphate, 1-ethyl-1-methylpyrrolidinium hexafluorophosphate, 1-butyl-3-methylpyridinium hexafluorophosphate, 1-methyl-4-methylpyridinium hexafluorophosphate, 1-ethyl-4-methylpyridinium chloride, 1-butyl-4-methylpyridinium hexafluorophosphate, 1-hexadecyl-4-methylpyridinium hexafluorophosphate, 4-dimethylamino-1-neopentylpyridinium hexafluorophosphate, 1-octadecyl-4-(4-phenyl-1,3-butadienyl)pyridinium hexafluorophosphate, 1-amino-2-methylpyridinium hexafluorophosphate, 1 -methylpyridinium tetrafluoroborate, 1-ethylpyridinium tetrafluoroborate, 1-butylpyridinium tetrafluoroborate, 1-octylpyridinium tetrafluoroborate, 1-acetonylpyridinium tetrafluoroborate, 1-methyl-3-methylpyridinium tetrafluoroborate, 1-ethyl-1-methylpyrrolidinium tetrafluoroborate, 1-butyl-3-methylpyridinium tetrafluoroborate, 1-methyl-4-methylpyridinium tetrafluoroborate Examples of the fluorine compound having a pyridine skeleton include pyridinium salts such as 1-octadecyl-4-methylpyridinium tetrafluoroborate, 1-ethyl-4-methylpyridinium tetrafluoroborate, 1-butyl-4-methylpyridinium tetrafluoroborate, 1-hexadecyl-4-methylpyridinium tetrafluoroborate, 4-dimethylamino-1-neopentylpyridinium tetrafluoroborate, 1-octadecyl-4-(4-phenyl-1,3-butadienyl)pyridinium tetrafluoroborate, and 1-amino-2-methylpyridinium tetrafluoroborate. The above-mentioned fluorine compounds having a pyridine skeleton may be used alone or in a mixture of two or more.

[0049] [Fluorine Compound Having a Phosphonic Acid Skeleton] Examples of fluorine compounds having a phosphonic acid skeleton include tetramethylphosphonium hexafluorophosphate, tetraethylphosphonium hexafluorophosphate, tetrabutylphosphonium hexafluorophosphate, tributylhexylphosphonium hexafluorophosphate, tributylhexadecylphosphonium hexafluorophosphate, tributyl-n-octylphosphonium hexafluorophosphate, tetra-n-octylphosphonium hexafluorophosphate, tetraphenylphosphonium hexafluorophosphate, triphenylphosphonium hexafluorophosphate, (3-methoxybenzyl)triphenylphosphonium hexafluorophosphate, (formylmethyl)triphenylphosphonium hexafluorophosphate, (cyanomethyl)tributylphosphonium hexafluorophosphate, trihexyl(tetradecyl)phosphonium hexafluorophosphate, bromotris(dimethylamino)phosphonium hexafluorophosphate, di-tert-butyl(methyl)phosphonium hexafluorophosphate, tetramethylphosphonium tetrafluorophosphate, and phosphonium salts such as fluoroboric acid, tetraethylphosphonium tetrafluoroborate, tetrabutylphosphonium tetrafluoroborate, tributylhexylphosphonium tetrafluoroborate, tributylhexadecylphosphonium tetrafluoroborate, tributyl-n-octylphosphonium tetrafluoroborate, tetra-n-octylphosphonium tetrafluoroborate, tetraphenylphosphonium tetrafluoroborate, triphenylphosphonium tetrafluoroborate, (3-methoxybenzyl)triphenylphosphonium tetrafluoroborate, (formylmethyl)triphenylphosphonium tetrafluoroborate, (cyanomethyl)tributylphosphonium tetrafluoroborate, trihexyl(tetradecyl)phosphonium tetrafluoroborate, bromotris(dimethylamino)phosphonium tetrafluoroborate, di-tert-butyl(methyl)phosphonium tetrafluoroborate, and tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide. The above-mentioned fluorine compounds having a phosphonic acid skeleton may be used alone or in a mixture of two or more kinds.

[0050] [Fluorine Compound Having a Quaternary Ammonium Skeleton] Examples of fluorine compounds having a quaternary ammonium skeleton include ammonium hexafluorophosphate, tetraethylammonium fluoride trifluoride water, tetraethylammonium fluoride tetrahydrofluoride, tetramethylammonium hexafluorophosphate, tetraethylammonium hexafluorophosphate, tetrabutylammonium hexafluorophosphate, ammonium tetrafluoroborate, tetramethylammonium tetrafluoroborate, triethylmethylammonium tetrafluoroborate, tetraethylammonium tetrafluoroborate, tetrabutylammonium tetrafluoroborate, hexadecyltrimethylammonium tetrafluoroborate, [(oxide)phenyl(trifluoromethyl)-λ4-sulfanylidene]dimethylammonium tetrafluoroborate, cyclohexyltrimethylammonium bis(trifluoromethanesulfonyl)imide, trimethylpropylammonium bis(trifluoromethanesulfonyl)imide, tributylmethylammonium bis(trifluoromethanesulfonyl)imide, and ethyl(3-methoxypropyl)dimethylammonium bis(trifluoromethanesulfonyl)imide. The above-mentioned fluorine compounds having a quaternary ammonium skeleton may be used alone or in a mixture of two or more kinds.

[0051] <Volatilization Inhibitor> The etching solution composition according to the present invention contains a volatilization inhibitor that suppresses the volatilization of fluorine compounds. The volatilization inhibitor does not contain fluorine atoms. The content of the volatilization inhibitor in the etching solution composition is preferably 0.01 to 5 wt %, more preferably 0.1 to 1 wt %. Examples of the volatilization inhibitor include compounds or salts having an imidazolium skeleton, a pyrrolidinium skeleton, a piperidinium skeleton, a morphonium skeleton, a pyridinium skeleton, a quaternary phosphonium skeleton, a quaternary ammonium skeleton, and a sulfonium skeleton, and the salts are also called ionic liquids. Examples of the ionic liquid include imidazolium salts, pyrrolidinium salts, piperidinium salts, pyridinium salts, morphonium salts, phosphonium salts, quaternary ammonium salts, and sulfonium salts. The ionic liquid may have a counter cation such as an imidazolium skeleton, a pyrrolidinium skeleton, a piperidinium skeleton, a morphonium skeleton, a pyridinium skeleton, a quaternary phosphonium skeleton, a quaternary ammonium skeleton, or a sulfonium skeleton, and a counter anion such as Br － , (CN) ２ N － , Cl － , I － , C.H. ３ COO － , HSO ４ － , (CH ３ ) ２ P.O. ４ － , C.H. ３ SO ３ － , and SCN － The above ionic liquids may be used alone or in a mixture of two or more kinds.

[0052] [Compound Having an Imidazole Skeleton] Examples of compounds having an imidazole skeleton include compounds such as imidazole, imidazole carboxylic acid, imido urea, diazolidinyl urea, 3-(2-oxoimidazolidin-1-yl)benzoic acid, and imidazole hydrochloride, as well as 1,3-dimethylimidazolium chloride, 1-methyl-3-methylimidazolium chloride, 1-methyl-3-propylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium chloride, 1-butyl-2,3-dimethylimidazolium chloride, and the like. Imidazolium chloride, 1-hexyl-3-methylimidazolium chloride, 1-allyl-3-methylimidazolium chloride, 1,3-dimethylimidazolium bromide, 1-methyl-3-methylimidazolium bromide, 1-methyl-3-propylimidazolium bromide, 1-ethyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium bromide, 1-butyl-2,3-dimethylimidazolium bromide, 1-hexyl-3-methylimidazolium bromide, 1-allyl-3-methyl Imidazolium bromide, 1,3-dimethylimidazolium iodide, 1-methyl-3-methylimidazolium iodide, 1-methyl-3-propylimidazolium iodide, 1-ethyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium iodide, 1-butyl-2,3-dimethylimidazolium iodide, 1-hexyl-3-methylimidazolium iodide, 1-allyl-3-methylimidazolium iodide, 1-ethyl-3-methylimidazolium thiocyanate, 1,3-dimethyl Examples of the imidazolium salt include imidazolium methyl sulfate, 1-methyl-3-methylimidazolium hydrogen sulfate, 1-butyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium nitrate, 1-butyl-3-methylimidazolium dibutyl phosphate, 1-ethyl-3-methylimidazolium dicyanamide, 1-butyl-3-methylimidazolium dicyanamide, and 1,3-dimethylimidazolium dimethyl phosphate. The above compounds having an imidazole skeleton may be used alone or in a mixture of two or more.

[0053] [Compound Having a Pyrrolidine Skeleton] Examples of compounds having a pyrrolidine skeleton include compounds such as pyrrolidine, 2-pyrrolidone, N-methylpyrrolidone, N-vinyl-2-pyrrolidone, pyroglutamic acid, and piracetam, as well as 1-methyl-1-methylpyrrolidinium chloride, 1-ethyl-1-methylpyrrolidinium chloride, 1-butyl-1-methylpyrrolidinium chloride, 1-methyl-1-ethylpyrrolidinium chloride, 1-ethyl-1-ethylpyrrolidinium chloride, 1-butyl-1-ethylpyrrolidinium chloride, and 1-methylpyrrolidinium chloride. 1-butyl-1-butylpyrrolidinium chloride, 1-ethyl-1-butylpyrrolidinium chloride, 1-butyl-1-butylpyrrolidinium chloride, 1-methyl-1-propylpyrrolidin-1-ium chloride, 1-ethyl-1-propylpyrrolidin-1-ium chloride, 1-butyl-1-propylpyrrolidin-1-ium chloride, 1-methyl-1-octylpyrrolidin-1-ium chloride, 1-ethyl-1-octylpyrrolidin-1-ium chloride, 1-butyl-1-octylpyrrolidin-1- 1-methyl-1-methylpyrrolidinium bromide, 1-ethyl-1-methylpyrrolidinium bromide, 1-butyl-1-methylpyrrolidinium bromide, 1-methyl-1-ethylpyrrolidinium bromide, 1-ethyl-1-ethylpyrrolidinium bromide, 1-butyl-1-ethylpyrrolidinium bromide, 1-methyl-1-butylpyrrolidinium bromide, 1-ethyl-1-butylpyrrolidinium bromide, 1-butyl-1-butylpyrrolidinium bromide, 1-methyl-1-propylpyrrolidinium bromide Examples of the compound having a pyrrolidine skeleton include pyrrolidinium salts such as pyrpyrrolidin-1-ium bromide, 1-ethyl-1-propylpyrrolidin-1-ium bromide, 1-butyl-1-propylpyrrolidin-1-ium bromide, 1-methyl-1-octylpyrrolidin-1-ium bromide, 1-ethyl-1-octylpyrrolidin-1-ium bromide, 1-butyl-1-octylpyrrolidin-1-ium bromide, 1-ethyl-1-methylpyrrolidinium allylsulfonate, and 1-ethyl-1-methylpyrrolidinium acetate. The compounds having a pyrrolidine skeleton may be used alone or in a mixture of two or more.

[0054] [Compound Having a Piperidine Skeleton] Examples of compounds having a piperidine skeleton include piperidine, ethyl piperidine-4-carboxylate, piperidin-2-ylacetic acid, and piperidine-4-carboxylic acid methylamide, as well as piperidinium salts such as 1,1-dimethylpiperidinium chloride, 1-methyl-1-propylpiperidinium chloride, 1-ethyl-1-propylpiperidinium chloride, 1-butyl-1-methylpiperidinium chloride, 1,1-dimethylpiperidinium bromide, 1-methyl-1-propylpiperidinium bromide, 1-ethyl-1-methylpiperidinium bromide, and 1-butyl-1-methylpiperidinium bromide. The above-mentioned compounds having a piperidine skeleton may be used alone or in a mixture of two or more.

[0055] [Compounds Having a Pyridine Skeleton] Examples of compounds having a pyridine skeleton include compounds such as pyridine, N,N-dimethyl-4-aminopyridine, bipyridine, 2,6-lutidine, and pyridinium p-toluenesulfonate, as well as 1-methylpyridinium chloride, 1-ethylpyridinium chloride, 1-butylpyridinium chloride, 1-acetonylpyridinium chloride, 1-methyl-3-methylpyridinium chloride, 1-ethyl-3-methylpyridinium chloride, and 1-butyl-3-methylpyridinium chloride. chloride, 1-methyl-4-methylpyridinium chloride, 1-ethyl-4-methylpyridinium chloride, 1-butyl-4-methylpyridinium chloride, 1-hexadecyl-4-methylpyridinium chloride, 4-dimethylamino-1-neopentylpyridinium chloride, 1-octadecyl-4-(4-phenyl-1,3-butadienyl)pyridinium chloride, 1-amino-2-methylpyridinium chloride, 1-methyl-3-methylpyridinium bromide, 1-ethyl 1-Hexadecyl-4-methylpyridinium bromide, 4-dimethylamino-1-neopentylpyridinium bromide, 1-octadecyl-4-(4-phenyl-1,3-butadienyl)pyridinium bromide, 1-amino-2-methylpyridinium bromide, 1-methyl-4-methylpyridinium bromide, 1-ethyl-4-methylpyridinium bromide, 1-butyl-4-methylpyridinium bromide, 1-hexadecyl-4-methylpyridinium bromide, 4-dimethylamino-1-neopentylpyridinium bromide, 1-octadecyl-4-(4-phenyl-1,3-butadienyl)pyridinium bromide, 1-amino-2-methylpyridinium bromide pyridinium bromide, 1-methylpyridinium iodide, 1-ethylpyridinium iodide, 1-butylpyridinium iodide, 1-acetonylpyridinium iodide, 1-butyl-3-methylpyridinium iodide, 1-ethyl-4-methylpyridinium iodide, 1-butyl-4-methylpyridinium iodide, 1-hexadecyl-4-methylpyridinium iodide, 4-dimethylamino-1-neopentylpyridinium iodide, 1-octadecyl-4-(4-phenyl-1,Examples of the compound having a pyridine skeleton include pyridinium salts such as 1-ethyl-3-methylpyridinium ethylsulfonate, 1-ethyl-3-(hydroxymethyl)pyridinium ethylsulfonate, 1-ethyl-3-(butadienyl)pyridinium iodide, 1-amino-2-methylpyridinium iodide, 1-methyl-2-(2-pyridyl)pyridinium iodide, hexadecylpyridinium bromide hydrate, 1-ethyl-3-methylpyridinium ethylsulfonate, and 1-ethyl-3-(hydroxymethyl)pyridinium ethylsulfonate. The compounds having a pyridine skeleton may be used alone or in combination of two or more.

[0056] [Compound Having a Morpholine Skeleton] Examples of compounds having a morpholine skeleton include compounds such as morpholine, morpholin-2-ylmethanol, morpholin-3-one, morpholine-4-carbothioic acid amide, morpholin-4-ylacetic acid, and ethyl morpholin-4-ylacetate, as well as morphonium salts such as 4-methyl-4-methylmorpholinium chloride, 4-ethyl-4-methylmorpholinium chloride, 4-methyl-4-methylmorpholinium bromide, 4-ethyl-4-methylmorpholinium bromide, 4-(chloromethyl)-4-methylmorpholinium, and 4-(2-ethoxyethyl)-4-methylmorpholinium bisimide. The above-mentioned compounds having a morpholine skeleton may be used alone or in a mixture of two or more.

[0057] [Compound Having a Phosphonic Acid Skeleton] Examples of compounds having a phosphonic acid skeleton include compounds such as phosphonic acid, diphenyl phosphonate, butyl phosphonate, dipentyl phosphonate, and ammonium phosphate, as well as tetrabutyl phosphonium hydroxide, tetrabutyl phosphonium chloride, tributylhexyl phosphonium chloride, tributylhexadecyl phosphonium chloride, tributyl-n-octyl phosphonium chloride, tetra-n-octyl phosphonium chloride, tetraphenyl phosphonium chloride, triphenyl phosphonium chloride, (3-methoxybenzyl)triphenyl phosphonium chloride, (formylmethyl)triphenyl phosphonium chloride, (cyanomethyl)tributyl phosphonium chloride, trihexyl(tetradecyl)phosphonium chloride, tetrabutyl phosphonium bromide, tributylhexyl phosphonium bromide, tributyl Examples of the phosphonium salts include hexadecylphosphonium bromide, tributyl-n-octylphosphonium bromide, tetra-n-octylphosphonium bromide, tetraphenylphosphonium bromide, triphenylphosphonium bromide, (3-methoxybenzyl)triphenylphosphonium bromide, (formylmethyl)triphenylphosphonium bromide, (cyanomethyl)tributylphosphonium bromide, trihexyl(tetradecyl)phosphonium bromide, tributylmethylphosphonium iodide, ethyltriphenylphosphonium iodide, tributyl(methyl)phosphonium dimethylphosphate, tributyl(ethyl)phosphonium diethylphosphate, tetrakis(hydroxymethyl)phosphonium sulfate, trihexyl(tetradecyl)phosphonium dicyanamide, and tetrabutylphosphonium benzotriazolate. The compounds having a phosphonic acid skeleton described above may be used alone or in a mixture of two or more.

[0058] [Compounds Having a Quaternary Ammonium Skeleton] Examples of compounds having a quaternary ammonium skeleton include tetramethylammonium chloride, tetrabutylammonium chloride, tetrapentylammonium chloride, octyltrimethylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide, tetrapentylammonium bromide, octyltrimethylammonium bromide, tetramethylammonium hydroxide, tetramethylammonium iodide, tetrapentylammonium iodide, octyltrimethylammonium iodide, tetrabutylammonium iodide, tetrabutylammonium hydrogen sulfate, and choline acetate. The above-mentioned compounds having a quaternary ammonium skeleton may be used alone or in a mixture of two or more.

[0059] <Etching Inhibitor> The etching solution composition according to the present invention contains an etching inhibitor that inhibits etching of silicon oxide. The etching inhibitor includes multiple types of etching inhibitors with different chemical structures. In this embodiment, the etching inhibitors include a first etching inhibitor and a second etching inhibitor. The first etching inhibitor is preferably a compound having three or less alkoxy groups, hydroxyl groups, and / or functional groups that serve as hydroxyl group precursors in its molecular structure, more preferably a silane compound having an amino group. The second etching inhibitor is preferably a compound having four or more alkoxy groups, hydroxyl groups, and / or functional groups that serve as hydroxyl group precursors in its molecular structure, more preferably a silane compound having at least one functional group selected from the group consisting of an alkyl group, an amino group, and a halogen group. The compound having a hydroxyl group may be any compound that can ultimately be converted to have a hydroxyl group in the solution.

[0060] [First Etching Inhibitor] Examples of the first etching inhibitor include methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, dimethoxydiphenylsilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, 1,6-bis(trimethoxysilyl)hexane, vinyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and N-2-(aminoethyl)-4-aminobutyltrimethoxysilane. silane, N-2-(aminoethyl)-5-aminopentyltrimethoxysilane, N-2-(aminoethyl)-6-aminohexyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane, and hydrochlorides of each of the above aminosilanes, tris-(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-isocyanatopropyltriethoxysilane, and 3-trimethoxysilylpropylsuccinic anhydride, as well as hydrolysates of each of the above alkoxysilanes. Among these first etching inhibitors, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, as well as hydrolysates of these alkoxysilanes, are preferred. The above first etching inhibitors may be used alone or in combination of two or more.

[0061] Second Etching Inhibitor The second etching inhibitor generally has the chemical structure shown in formula (I) below.

[0062] Here, R in formula (I) １ ~R ６ are substituents, at least four of which are at least one specific substituent selected from the group consisting of an alkoxy group, a hydroxyl group, and chlorine, and the substituents other than the specific substituents are at least one substituent selected from the group consisting of an alkyl group, an aryl group, a carbonyl group, a carboxyl group, an amino group, an ethylenediamine group, and derivatives or composite groups of these substituents. X in formula (I) is "O" (oxygen atom) or "-" (single bond). n in formula (I) is an integer from 0 to 3. Thus, the second etching inhibitor may be a compound having an alkoxy group (a siloxane compound or a disilane compound, the same applies hereinafter) and a compound having a hydroxyl group, or a compound having a chlorine group. Note that the compound having an alkoxy group and the compound having a chlorine group are ultimately converted to a compound having a hydroxyl group by hydrolysis.

[0063] Specific examples of the second etching inhibitor include those represented by the following chemical structural formula (1):

[0064] 1,3-dimethyltetramethoxydisiloxane shown in the following chemical structural formula (2):

[0065] a siloxane compound represented by the following chemical structural formula (3):

[0066] a siloxane compound represented by the following chemical structural formula (4):

[0067] Hexamethoxydisiloxane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, hexamethoxydisilane, hexaethoxydisilane, hexabutoxydisilane, hexamethoxydisiloxane, hexaethoxydisiloxane, hexabutoxydisiloxane, 1,3-dimethyltetraethoxydisiloxane, 1,3-dimethyltetrabutoxydisiloxane, 1,3-diethyltetramethoxydisiloxane, 1,3-diethyltetraethoxydisiloxane, 1,3 Examples of the second etching inhibitor include 1,3-dimethyltetrachlorodisiloxane, 1,3-diethyltetrabutoxydisiloxane, 1,3-divinyltetramethoxydisiloxane, 1,3-divinyltetraethoxydisiloxane, 1,3-divinyltetrabutoxydisiloxane, 1,3-bis(3-aminopropyl)tetramethoxydisiloxane, silicon tetrachloride, hexachlorodisilane, hexachlorodisiloxane, 1,3-dimethyltetrachlorodisiloxane, 1,3-diethyltetrachlorodisiloxane, and 1,3-dibutyltetrachlorodisiloxane. Commercially available siloxane compounds include silane coupling agents "X-12-1098," "X-12-1135," "KBP-64," and "KBP-90" manufactured by Shin-Etsu Chemical Co., Ltd. The second etching inhibitors may be used alone or in a mixture of two or more.

[0068] [Content of Etching Inhibitor] With regard to the content of the etching inhibitor in the etching solution composition, the content of the first etching inhibitor is preferably 0.5 to 20 wt %, more preferably 1 to 20 wt %, and even more preferably 1 to 6 wt %. The content of the second etching inhibitor is preferably 0.01 to 10 wt %, more preferably 0.01 to 5 wt %, and even more preferably 0.09 to 0.6 wt %.

[0069] <Deposition Inhibitor> The etching solution composition of the present invention contains a deposition inhibitor that inhibits silica deposition on the surface of silicon oxide. Examples of deposition inhibitors include hydrazine compounds, pyrazoles, triazoles, hydrazides, compounds having an imidazole skeleton, compounds having a pyrrolidine skeleton, compounds having a piperidine skeleton, compounds having a morpholine skeleton, compounds having a pyridine skeleton, phosphonic acid compounds, compounds having a quaternary ammonium skeleton, compounds having a pyrimidine skeleton, compounds having a purine skeleton, and compounds having a urea skeleton, with hydrazides being preferred. The above compounds and compounds may be used alone or in a mixture of two or more. Using two or more different deposition inhibitors can be extremely useful not only in terms of performance in the etching process but also in terms of extending the life of the solution and reducing costs. The content of the deposition inhibitor in the etching solution composition is preferably 0.1 to 1 wt %, more preferably 0.3 to 0.4 wt %.

[0070] [Hydrazine Compound] Examples of the hydrazine compound include hydrazine, propylhydrazine, isopropylhydrazine, butylhydrazine, benzylhydrazine, N,N-dimethylhydrazine, 1,2-diacetylhydrazine, phenylhydrazine, N,N-dicarbamoylhydrazine, hydrazine sulfate, hydrazine monohydrochloride, hydrazine dihydrochloride, butylhydrazine hydrochloride, hydrazine carbonate, and hydrazine monohydrobromide. The above hydrazine compounds may be used alone or in a mixture of two or more.

[0071] [Pyrazoles] Examples of pyrazoles include 3,5-dimethylpyrazole, 3-methyl-5-pyrazone, etc. The above pyrazoles may be used alone or in a mixture of two or more kinds.

[0072] [Triazoles] Examples of triazoles include 4-amino-1,2,4-triazole, 1,2,4-triazole, 1,2,3-triazole, 1-hydroxybenzotriazole, and 3-mercapto-1,2,4-triazole. The above triazoles may be used alone or in a mixture of two or more.

[0073] [Hydrazides] Examples of hydrazides include propionic acid hydrazide, lauric acid hydrazide, salicylic acid hydrazide, formhydrazide, acetohydrazide, acetohydrazide chloride, p-hydroxybenzoic acid hydrazide, naphthoic acid hydrazide, 3-hydroxy-2-naphthoic acid hydrazide, benzhydrazide, carbodihydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, succinic acid 2,2 dimethylhydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide, dodecanedioic acid dihydrazide, maleic acid dihydrazide, hydrazide, fumaric acid dihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, diglycolic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, 2,6-naphthalenedicarboxylic acid dihydrazide, 2,6-naphthoic acid dihydrazide, citric acid trihydrazide, pyromellitic acid trihydrazide, 1,2,4-benzenetricarboxylic acid trihydrazide, nitrilotriacetic acid trihydrazide, 1,3,5-cyclohexanetricarboxylic acid trihydrazide, ethylenediaminetetraacetic acid tetrahydrazide, and 1,4,5,8-naphthoic acid tetrahydrazide, etc. Of these hydrazides, adipic acid dihydrazide, succinic acid dihydrazide, acetohydrazide chloride, succinic acid 2,2-dimethylhydrazide, and azelaic acid dihydrazide are preferred. The above hydrazides may be used alone or in a mixture of two or more kinds.

[0074] [Compound Having an Imidazole Skeleton] Examples of compounds having an imidazole skeleton include compounds such as imidazole, imidazole carboxylic acid, imido urea, diazolidinyl urea, 3-(2-oxoimidazolidin-1-yl)benzoic acid, and imidazole hydrochloride, as well as 1,3-dimethylimidazolium chloride, 1-methyl-3-methylimidazolium chloride, 1-methyl-3-propylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium chloride, 1-butyl-2-methylimidazolium chloride, and 1-butyl-3-methylimidazolium chloride. ,3-dimethylimidazolium chloride, 1-hexyl-3-methylimidazolium chloride, 1-allyl-3-methylimidazolium chloride, 1,3-dimethylimidazolium bromide, 1-methyl-3-methylimidazolium bromide, 1-methyl-3-propylimidazolium bromide, 1-ethyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium bromide, 1-butyl-2,3-dimethylimidazolium bromide, 1-hexyl-3-methylimidazolium imidazolium bromide, 1-allyl-3-methylimidazolium bromide, 1,3-dimethylimidazolium iodide, 1-methyl-3-methylimidazolium iodide, 1-methyl-3-propylimidazolium iodide, 1-ethyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium iodide, 1-butyl-2,3-dimethylimidazolium iodide, 1-hexyl-3-methylimidazolium iodide, 1-allyl-3-methylimidazolium iodide, 1-ethyl 1-ethyl-3-methylimidazolium thiocyanate, 1,3-dimethylimidazolium methyl sulfate, 1-butyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium nitrate, 1-butyl-3-methylimidazolium dibutyl phosphate, 1-ethyl-3-methylimidazolium dicyanamide, 1-butyl-3-methylimidazolium dicyanamide and 1,3-dimethylimidazolium dimethyl phosphate, 1,3-Dimethylimidazolium hexafluorophosphate, 1-methyl-3-propylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-2,3-dimethylimidazolium hexafluorophosphate, 1-hexyl-3-methylimidazolium hexafluorophosphate, 1-methyl-3-octylimidazolium hexafluorophosphate, 1-ethyl-3-octylimidazolium hexafluorophosphate, 1-butyl-3-octylimidazolium hexafluorophosphate, 1,3-dimethylimidazolium Examples of imidazolium salts include 1-methyl-3-propylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-methyl-3-octylimidazolium tetrafluoroborate, 1-ethyl-3-octylimidazolium tetrafluoroborate, and 1-butyl-3-octylimidazolium tetrafluoroborate. The above compounds having an imidazole skeleton may be used alone or in a mixture of two or more.

[0075] [Compounds Having a Pyrrolidine Skeleton] Examples of compounds having a pyrrolidine skeleton include compounds such as pyrrolidine, 2-pyrrolidone, N-methylpyrrolidone, N-vinyl-2-pyrrolidone, pyroglutamic acid, and piracetam, as well as 1-methyl-1-methylpyrrolidinium chloride, 1-ethyl-1-methylpyrrolidinium chloride, 1-butyl-1-methylpyrrolidinium chloride, 1-methyl-1-propylpyrrolidin-1-ium chloride, 1-ethyl-1-propylpyrrolidin-1-ium chloride, 1-butyl-1-propylpyrrolidin-1-ium chloride, and 1-methyl -1-octylpyrrolidin-1-ium chloride, 1-ethyl-1-octylpyrrolidin-1-ium chloride, 1-butyl-1-octylpyrrolidin-1-ium chloride, 1-methyl-1-methylpyrrolidinium bromide, 1-ethyl-1-methylpyrrolidinium bromide, 1-butyl-1-methylpyrrolidinium bromide, 1-ethyl-1-ethylpyrrolidinium bromide, 1-butyl-1-methylpyrrolidinium bromide, 1-methyl-1-propylpyrrolidin-1-ium bromide, 1-ethyl-1-propylpyrrolidin-1- 1-butyl-1-propylpyrrolidin-1-ium bromide, 1-methyl-1-octylpyrrolidin-1-ium bromide, 1-ethyl-1-octylpyrrolidin-1-ium bromide, 1-butyl-1-octylpyrrolidin-1-ium bromide, 1-ethyl-1-butylpyrrolidinium bromide, 1-ethyl-1-butylpyrrolidinium bromide, 1-ethyl-1-methylpyrrolidinium allylsulfonate, 1-ethyl-1-methylpyrrolidinium acetate, 1-methyl-1-methylpyrrolidinium hexafluorophosphate, 1-ethyl-1-methylpyrrolidinium hexafluorophosphate hexafluorophosphate, 1-butyl-1-methylpyrrolidinium hexafluorophosphate, 1-methyl-1-propylpyrrolidin-1-ium hexafluorophosphate, 1-ethyl-1-propylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-propylpyrrolidin-1-ium hexafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-ethyl-1-octylpyrrolidin-1-ium hexafluorophosphate, 1-butyl-1-octylpyrrolidin-1-ium hexafluorophosphate,Examples of such compounds include pyrrolidinium salts such as 1-ethyl-1-methylpyrrolidinium tetrafluoroborate, 1-butyl-1-methylpyrrolidinium tetrafluoroborate, 1-methyl-1-propylpyrrolidin-1-ium tetrafluoroborate, 1-ethyl-1-propylpyrrolidin-1-ium tetrafluorophosphate, 1-butyl-1-propylpyrrolidin-1-ium tetrafluorophosphate, 1-methyl-1-octylpyrrolidin-1-ium tetrafluoroborate, 1-ethyl-1-octylpyrrolidin-1-ium tetrafluorophosphate, and 1-butyl-1-octylpyrrolidin-1-ium tetrafluoroborate. The compounds having a pyrrolidine skeleton may be used alone or in a mixture of two or more.

[0076] [Compound Having a Piperidine Skeleton] Examples of compounds having a piperidine skeleton include piperidine, ethyl piperidine-4-carboxylate, piperidin-2-ylacetic acid, and piperidine-4-carboxylic acid methylamide, as well as 1,1-dimethylpiperidinium chloride, 1-methyl-1-propylpiperidinium chloride, 1-ethyl-1-propylpiperidinium chloride, 1-butyl-1-methylpiperidinium chloride, 1,1-dimethylpiperidinium bromide, 1-methyl-1-propylpiperidinium bromide, 1-ethyl-1-methylpiperidinium bromide, and 1-butyl-1-methylpiperidinium bromide, 1,1-dimethylpiperidinium hexafluorophosphate, 1-methyl-1-propylpiperidinium hexafluorophosphate, 1-ethyl Examples of the compound having a piperidine skeleton include piperidinium salts such as 1-propylpiperidinium hexafluorophosphate, 1-butyl-1-methylpiperidinium hexafluorophosphate, 1,1-dimethylpiperidinium tetrafluoroborate, 1-methyl-1-propylpiperidinium tetrafluoroborate, 1-ethyl-1-methylpiperidinium tetrafluoroborate, 1-butyl-1-methylpiperidinium tetrafluoroborate, (piperidinium-1-ylmethyl)trifluoroborate, 1-(cyanomethyl)piperidinium tetrafluoroborate, 1-butyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, and 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide. The compounds having a piperidine skeleton may be used alone or in a mixture of two or more.

[0077] [Compound Having a Morpholine Skeleton] Examples of the compound having a morpholine skeleton include compounds such as morpholine, morpholin-2-ylmethanol, morpholin-3-one, morpholine-4-carbothioic acid amide, morpholin-4-ylacetic acid, and ethyl morpholin-4-ylacetate, as well as morphonium salts such as 4-methyl-4-methylmorpholinium chloride, 4-ethyl-4-methylmorpholinium chloride, 4-methyl-4-methylmorpholinium bromide, 4-ethyl-4-methylmorpholinium bromide, 4-(chloromethyl)-4-methylmorpholinium, 4-(2-ethoxyethyl)-4-methylmorpholinium bisimide, 4-methyl-4-methylmorpholinium hexafluorophosphate, 4-ethyl-4-methylmorpholinium hexafluorophosphate, 4-methyl-4-methylmorpholinium tetrafluoroborate, and 4-ethyl-4-methylmorpholinium tetrafluoroborate. The above-mentioned compounds having a morpholine skeleton may be used alone or in a mixture of two or more kinds.

[0078] [Compound Having a Pyridine Skeleton] Examples of compounds having a pyridine skeleton include compounds such as pyridine, N,N-dimethyl-4-aminopyridine, bipyridine, 2,6-lutidine, and pyridinium p-toluenesulfonate, as well as pyridinium salts such as 1-butyl-3-methylpyridium chloride, 1-butylpyridium tetrafluoroborate, and 1-butyl-pyridium hexafluorophosphate. The above compounds having a pyridine skeleton may be used alone or in a mixture of two or more.

[0079] [Phosphonic Acid Compound] Examples of the phosphonic acid compound include compounds such as phosphonic acid, diphenyl phosphonate, butyl phosphonate, dipentyl phosphonate, and ammonium phosphate, as well as tetrabutyl phosphonium hydroxide, tetrabutyl phosphonium chloride, tributylhexyl phosphonium chloride, tributylhexadecyl phosphonium chloride, tributyl-n-octyl phosphonium chloride, tetra-n-octyl phosphonium chloride, tetraphenyl phosphonium chloride, triphenyl phosphonium chloride, (3-methoxybenzyl )triphenylphosphonium chloride, (formylmethyl)triphenylphosphonium chloride, (cyanomethyl)tributylphosphonium chloride, trihexyl(tetradecyl)phosphonium chloride, tetrabutylphosphonium bromide, tributylhexylphosphonium bromide, tributylhexadecylphosphonium bromide, tributyl-n-octylphosphonium bromide, tetra-n-octylphosphonium bromide, tetraphenylphosphonium bromide, triphenylphosphonium bromide, (3-methoxybenzene (methyl)triphenylphosphonium bromide, (formylmethyl)triphenylphosphonium bromide, (cyanomethyl)tributylphosphonium bromide, trihexyl(tetradecyl)phosphonium bromide, tributylmethylphosphonium iodide, ethyltriphenylphosphonium iodide, tributyl(methyl)phosphonium dimethylphosphate, tributyl(ethyl)phosphonium diethylphosphate, tetrakis(hydroxymethyl)phosphonium sulfate, trihexyl(tetradecyl)phosphonium dicyanamide, tetrabutylphosphonium benzotriazolate, tetramethylphosphonium hexafluorophosphate, tetraethylphosphonium hexafluorophosphate, tetrabutylphosphonium hexafluorophosphate, tributylhexylphosphonium hexafluorophosphate, tributylhexylhexadecylphosphonium hexafluorophosphate, tributyl-n-octylphosphonium hexafluorophosphate, tetra-n-octylphosphonium hexafluorophosphate, tetraphenylphosphonium hexafluorophosphate, triphenylphosphonium hexafluorophosphate,(3-Methoxybenzyl)triphenylphosphonium hexafluorophosphate, (formylmethyl)triphenylphosphonium hexafluorophosphate, (cyanomethyl)tributylphosphonium hexafluorophosphate, trihexyl(tetradecyl)phosphonium hexafluorophosphate, bromotris(dimethylamino)phosphonium hexafluorophosphate, di-tert-butyl(methyl)phosphonium hexafluorophosphate, tetramethylphosphonium tetrafluoroborate, tetraethylphosphonium tetrafluoroborate, tetrabutylphosphonium tetrafluoroborate, tributylhexylphosphonium tetrafluoroborate, tributylhexadecylphosphonium tetrafluoroborate, tributyl-n-octylphosphonium Examples of suitable phosphonium salts include phosphonium tetrafluoroborate, tetra-n-octylphosphonium tetrafluoroborate, tetraphenylphosphonium tetrafluoroborate, triphenylphosphonium tetrafluoroborate, (3-methoxybenzyl)triphenylphosphonium tetrafluoroborate, (formylmethyl)triphenylphosphonium tetrafluoroborate, (cyanomethyl)tributylphosphonium tetrafluoroborate, trihexyl(tetradecyl)phosphonium tetrafluoroborate, bromotris(dimethylamino)phosphonium tetrafluoroborate, di-tert-butyl(methyl)phosphonium tetrafluoroborate, and tributylmethylphosphonium bis(trifluoromethanesulfonyl)imide. The above phosphonic acid compounds may be used alone or in a mixture of two or more.

[0080] [Compound Having a Quaternary Ammonium Skeleton] Examples of compounds having a quaternary ammonium skeleton include tetramethylammonium chloride, tetrabutylammonium chloride, tetrapentylammonium chloride, octyltrimethylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide, tetrapentylammonium bromide, octyltrimethylammonium bromide, tetramethylammonium hydroxide, tetramethylammonium iodide, tetrapentylammonium iodide, octyltrimethylammonium iodide, tetrabutylammonium iodide, tetrabutylammonium hydrogen sulfate, and choline acetate, tetraethylammonium fluoride trifluoride water, tetraethylammonium fluoride tetrahydrofluoride, tetramethylammonium hexafluorophosphate, tetraethylammonium hexafluorophosphate, tetraethylammonium hexafluorophosphate, tetramethylammonium hexafluorophosphate, tetramethylammonium iodide, tetramethylammonium hydroxide, tetramethylammonium iodide, tetrapentylammonium iodide, octyltrimethylammonium iodide, tetrabutylammonium iodide, tetrabutylammonium hydrogen sulfate, choline acetate, tetraethylammonium fluoride trifluoride water, tetraethylammonium fluoride tetrahydrofluoride, tetramethylammonium hexafluorophosphate, tetraethylammonium hexafluorophosphate, tetramethyl ... Examples of suitable quaternary ammonium compounds include tetramethylammonium tetrafluoroborate, tetrabutylammonium hexafluorophosphate, tetramethylammonium tetrafluoroborate, triethylmethylammonium tetrafluoroborate, tetraethylammonium tetrafluoroborate, tetrabutylammonium tetrafluoroborate, hexadecyltrimethylammonium tetrafluoroborate, [(oxide)phenyl(trifluoromethyl)-λ4-sulfanylidene]dimethylammonium tetrafluoroborate, cyclohexyltrimethylammonium bis(trifluoromethanesulfonyl)imide, trimethylpropylammonium bis(trifluoromethanesulfonyl)imide, tributylmethylammonium bis(trifluoromethanesulfonyl)imide, and ethyl(3-methoxypropyl)dimethylammonium bis(trifluoromethanesulfonyl)imide. The compounds having a quaternary ammonium skeleton may be used alone or in a mixture of two or more.

[0081] [Compounds Having a Pyrimidine Skeleton] Examples of compounds having a pyrimidine skeleton include thymine, cytosine, uracil, and nucleosides, ribonucleosides, and deoxyribonucleosides of the above-mentioned compounds. The above-mentioned compounds having a pyrimidine skeleton may be used alone or in a mixture of two or more.

[0082] [Compounds Having a Purine Skeleton] Examples of compounds having a purine skeleton include purine, adenine, guanine, uric acid, caffeine, hypoxanthine, xanthine, theophylline, theobromine, isoguanine, and nucleosides, ribonucleotides, and deoxyribonucleotides of the above-mentioned compounds. The above-mentioned compounds having a purine skeleton may be used alone or in a mixture of two or more.

[0083] [Compound Having a Urea Skeleton] Examples of the compound having a urea skeleton include urea, hydroxyurea, N,N-diethylthiourea, N,N-dibutylthiourea, biurea, biuret, N-amidinothiourea, etc. The above-mentioned compounds having a urea skeleton may be used alone or in a mixture of two or more.

[0084] [Preparation of Etching Solution Composition] The etching solution composition according to the present invention is prepared by adding (a) a fluorine compound and (b) a volatilization inhibitor to a base inorganic acid, and further adding (c) an etching inhibitor and (d) a precipitation inhibitor, if necessary. Here, the above-mentioned components (a) to (d) can be added directly to the inorganic acid, or the components (a) to (d) may be added to the inorganic acid in a dissolved or suspended state in a solvent. The addition of the components (a) to (d) to the inorganic acid may be carried out at room temperature, or may be carried out while heating the solution.

[0085] An example of the etching solution composition according to the present invention will be described. In this example, an etching test was carried out simulating a part of the manufacturing process of 3D NAND in order to confirm the performance of the etching solution composition.

[0086] <Preparation of Etching Solution Compositions> Etching solution compositions were prepared using phosphoric acid as the base inorganic acid. Specifically, etching solution compositions containing a fluorine compound and a volatilization inhibitor (Examples 1 to 5), etching solution compositions containing a fluorine compound and a volatilization inhibitor as well as a first etching inhibitor and a precipitation inhibitor (Examples 6 to 8), and etching solution compositions containing a fluorine compound and a volatilization inhibitor as well as a first etching inhibitor, a second etching inhibitor, and a precipitation inhibitor (Examples 9 to 11) were prepared. For comparison, etching solution compositions containing only a fluorine compound (Comparative Examples 1 to 8), etching solution compositions containing only a volatilization inhibitor (Comparative Examples 9 to 13), etching solution compositions containing a fluorine compound, a first etching inhibitor, and a precipitation inhibitor (Comparative Examples 14 to 17), and etching solution compositions containing a fluorine compound, a first etching inhibitor, a second etching inhibitor, and a precipitation inhibitor (Comparative Examples 18 to 23) were also prepared. Furthermore, as reference examples containing neither a fluorine compound nor a volatilization inhibitor, an etching solution consisting only of phosphoric acid (Reference Example 1), an etching solution composition containing a first etching inhibitor and a precipitation inhibitor (Reference Examples 2 and 3), and an etching solution composition containing a first etching inhibitor, a second etching inhibitor, and a precipitation inhibitor (Reference Examples 4 to 6) were prepared. Hereinafter, the preparation method of each etching solution composition or etching solution will be described.

[0087] Example 1: A phosphoric acid solution (manufactured by Rasa Kogyo Co., Ltd., hereinafter referred to as "85% phosphoric acid") adjusted to a concentration of 85 wt% was used as the base inorganic acid, which was then concentrated to obtain 87% phosphoric acid. To this 87% phosphoric acid, 0.030 wt% ammonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound and 0.20 wt% imidazole (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor were added, and a predetermined amount of silicon nitride was pre-dissolved to adjust the concentration of silicon derived from silicon nitride in the solution to 200 ppm. This was used as the etching solution composition of Example 1. The etching solution composition of Example 1 was heated at approximately 165°C for 3 hours before use in the etching process (the heating conditions were the same in the subsequent examples).

[0088] Example 2 0.030 wt % of ammonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound and 0.20 wt % of tetrabutylphosphonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor were added to 87% phosphoric acid obtained by the same procedure as in Example 1, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Example 2. This etching solution composition of Example 2 was heated before use in the etching process.

[0089] Example 3 0.030 wt % of tetrafluoroboric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound and 0.20 wt % of 1-butyl-3-methylpyridinium chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor were added to 87% phosphoric acid obtained by the same procedure as in Example 1, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Example 3. This etching solution composition of Example 3 was heated before use in the etching process.

[0090] Example 4 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.100 wt % of tetrafluoroboric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound and 0.50 wt % of tetrabutylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor were added, and the resulting solution was pre-dissolved in a predetermined amount of silicon nitride, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Example 4. This etching solution composition of Example 4 was heated before use in the etching process.

[0091] Example 5 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.020 wt% of tetramethylammonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound and 0.20 wt% of tetrabutylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor were added, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Example 5. This etching solution composition of Example 5 was heated before use in the etching process.

[0092] Example 6 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.100 wt% of 1-ethyl-3-methylimidazolium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 0.50% of tetramethylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor, 3.00 wt% of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, and 0.30 wt% of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm, to prepare the etching solution composition of Example 6. This etching solution composition of Example 6 was heated before use in the etching process.

[0093] Example 7 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.100 wt% of 1-ethyl-3-methylimidazolium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 0.70 wt% of a 74.1% aqueous solution of tetrakis(hydroxymethyl)phosphonium sulfate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a volatilization inhibitor, 3.00 wt% of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, and 0.30 wt% of azelaic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Example 7. This etching solution composition of Example 7 was heated before use in the etching process.

[0094] Example 8 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.020 wt% of 1-butyl-1-methylpyrrolidinium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 0.20 wt% of 1-ethyl-1-methylpyrrolidinium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor, 2.00 wt% of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, and 0.20 wt% of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from silicon nitride in the solution was adjusted to 200 ppm, to prepare the etching solution composition of Example 8. This etching solution composition of Example 8 was heated before use in the etching process.

[0095] Example 9 To 85% phosphoric acid, 0.150 wt% of tetraethylphosphonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 1.00 wt% of imidazole (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor, 7.50 wt% of a hydrolyzate of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.60 wt% of a siloxane compound having the chemical structural formula (2) as a second etching inhibitor, and 0.40 wt% of succinic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from silicon nitride in the solution was adjusted to 1000 ppm, to prepare the etching solution composition of Example 9. This etching solution composition of Example 9 was heated before use in the etching process.

[0096]

[0097] Example 10 To 85% phosphoric acid, 0.200 wt% of hexafluorophosphoric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 0.50 wt% of imidazole (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor, 5.50 wt% of a hydrolyzate of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.20 wt% of tetramethyl orthosilicate as a second etching inhibitor, and 0.20 wt% of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 500 ppm, to prepare the etching solution composition of Example 10. This etching solution composition of Example 10 was heated before use in the etching process.

[0098] Example 11 To 85% phosphoric acid, 0.200 wt% of hexafluorophosphoric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 1.00 wt% of imidazole (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a volatilization inhibitor, 5.50 wt% of a hydrolyzate of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.25 wt% of tetraethyl orthosilicate as a second etching inhibitor, and 0.20 wt% of succinic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 300 ppm, to prepare the etching solution composition of Example 11. This etching solution composition of Example 11 was heated before use in the etching process.

[0099] Comparative Example 1 0.030 wt % of ammonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound was added to 87% phosphoric acid obtained by the same procedure as in Example 1, and the solution was dissolved in a liquid, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the liquid was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 1. The etching solution composition of Comparative Example 1 was not heated before use in the etching treatment.

[0100] Comparative Example 2 The etching solution composition of Comparative Example 1 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 2.

[0101] Comparative Example 3 0.030 wt % of tetrafluoroboric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound was added to 87% phosphoric acid obtained by the same procedure as in Example 1, and the solution was dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 3. The etching solution composition of Comparative Example 3 was not heated before use in the etching treatment.

[0102] Comparative Example 4 The etching solution composition of Comparative Example 3 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 4.

[0103] Comparative Example 5 0.100 wt % of tetrafluoroboric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound was added to 87% phosphoric acid obtained by the same procedure as in Example 1, and the solution was dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 5. The etching solution composition of Comparative Example 5 was not heated before use in the etching treatment.

[0104] Comparative Example 6 The etching solution composition of Comparative Example 5 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 6.

[0105] Comparative Example 7 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.020 wt % of tetramethylammonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound was added, and the solution was dissolved in a liquid, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the liquid was adjusted to 200 ppm, to prepare the etching solution composition of Comparative Example 7. The etching solution composition of Comparative Example 7 was not heated before use in the etching treatment.

[0106] Comparative Example 8 The etching solution composition of Comparative Example 7 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 8.

[0107] Comparative Example 9 0.20 wt % of imidazole (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a volatilization inhibitor to 87% phosphoric acid obtained by the same procedure as in Example 1, and the mixture was dissolved in a solution to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 9. The etching solution composition of Comparative Example 9 was not heated before use in the etching treatment.

[0108] Comparative Example 10 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.20 wt % of tetrabutylphosphonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a volatilization inhibitor, and the mixture was dissolved in a solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm, to prepare the etching solution composition of Comparative Example 10. The etching solution composition of Comparative Example 10 was not heated before use in the etching treatment.

[0109] Comparative Example 11 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.20 wt % of tetrabutylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a volatilization inhibitor, and the solution was dissolved in a liquid. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from the silicon nitride in the liquid was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 11. The etching solution composition of Comparative Example 11 was not heated before being used in the etching treatment.

[0110] Comparative Example 12 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.70 wt % of a 74.1% aqueous solution of tetrakis(hydroxymethyl)phosphonium sulfate (Tokyo Chemical Industry Co., Ltd.) was added as a volatilization inhibitor, and the solution was dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 12. The etching solution composition of Comparative Example 12 was not heated before use in the etching treatment.

[0111] Comparative Example 13 0.20 wt % of 1-ethyl-1-methylpyrrolidinium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added as a volatilization inhibitor to 87% phosphoric acid obtained by the same procedure as in Example 1, and the mixture was dissolved in a solution to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Comparative Example 13. The etching solution composition of Comparative Example 13 was not heated before use in the etching treatment.

[0112] Comparative Example 14 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.100 wt% of 1-ethyl-3-methylimidazolium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 3.00 wt% of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, and 0.30 wt% of azelaic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from silicon nitride in the solution was adjusted to 200 ppm, to prepare the etching solution composition of Comparative Example 14. The etching solution composition of Comparative Example 14 was not heated before use in the etching process.

[0113] Comparative Example 15 The etching solution composition of Comparative Example 14 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 15.

[0114] Comparative Example 16 To 87% phosphoric acid obtained by the same procedure as in Example 1, 0.020 wt% of 1-butyl-1-methylpyrrolidinium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 2.00 wt% of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, and 0.20 wt% of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from silicon nitride in the solution was adjusted to 200 ppm, to prepare the etching solution composition of Comparative Example 16. The etching solution composition of Comparative Example 16 was not heated before use in the etching process.

[0115] Comparative Example 17 The etching solution composition of Comparative Example 16 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 17.

[0116] Comparative Example 18 To 85% phosphoric acid, 0.150 wt% of tetraethylphosphonium hexafluorophosphate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 7.50 wt% of a hydrolyzate of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.60 wt% of a siloxane compound having chemical structural formula (2) as a second etching inhibitor, and 0.40 wt% of succinic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from silicon nitride in the solution was adjusted to 1000 ppm, to prepare the etching solution composition of Comparative Example 18. The etching solution composition of Comparative Example 18 was not heated before use in the etching treatment.

[0117]

[0118] Comparative Example 19 The etching solution composition of Comparative Example 18 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 19.

[0119] Comparative Example 20 To 85% phosphoric acid, 0.200 wt% of hexafluorophosphoric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 5.50 wt% of a hydrolyzate of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.20 wt% of tetramethyl orthosilicate as a second etching inhibitor, and 0.20 wt% of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 500 ppm, to prepare the etching solution composition of Comparative Example 20. The etching solution composition of Comparative Example 20 was not heated before use in the etching process.

[0120] Comparative Example 21 The etching solution composition of Comparative Example 20 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 21.

[0121] Comparative Example 22 To 85% phosphoric acid, 0.200 wt% of hexafluorophosphoric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a fluorine compound, 5.50 wt% of a hydrolyzate of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.25 wt% of tetraethyl orthosilicate as a second etching inhibitor, and 0.20 wt% of succinic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added, and dissolved in the solution, to which a predetermined amount of silicon nitride was pre-dissolved, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 300 ppm, to prepare the etching solution composition of Comparative Example 22. The etching solution composition of Comparative Example 22 was not heated before use in the etching treatment.

[0122] Comparative Example 23 The etching solution composition of Comparative Example 22 was heated at 165° C. for 3 hours to prepare an etching solution composition of Comparative Example 23.

[0123] Reference Example 1 An etching solution composition (etching solution) of Reference Example 1 was prepared by adjusting the concentration of Si derived from silicon nitride in 87% phosphoric acid obtained by the same procedure as in Example 1 to 200 ppm.

[0124] Reference Example 2 3.00 wt % of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor and 0.30 wt % of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added to 87% phosphoric acid obtained by the same procedure as in Example 1, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Reference Example 2. This etching solution composition of Reference Example 2 was heated at 165° C. for 3 hours before use in the etching treatment (the heating conditions in the subsequent Reference Examples were the same).

[0125] Reference Example 3 2.00 wt % of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor and 0.20 wt % of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added to 87% phosphoric acid obtained by the same procedure as in Example 1, and dissolved in the solution. A predetermined amount of silicon nitride was then dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 200 ppm to prepare the etching solution composition of Reference Example 3. This etching solution composition of Reference Example 3 was heated before use in the etching treatment.

[0126] Reference Example 4 To 85% phosphoric acid, 7.50 wt % of a hydrolyzate of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.60 wt % of a siloxane compound having the chemical structural formula (2) as a second etching inhibitor, and 0.40 wt % of succinic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added and dissolved, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 1000 ppm to prepare the etching solution composition of Reference Example 4. This etching solution composition of Reference Example 4 was heated before use in the etching treatment.

[0127]

[0128] Reference Example 5 To 85% phosphoric acid, 5.50 wt % of a hydrolyzate of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.20 wt % of tetramethyl orthosilicate as a second etching inhibitor, and 0.20 wt % of adipic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added and dissolved, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 500 ppm to prepare the etching solution composition of Reference Example 5. This etching solution composition of Reference Example 5 was heated before use in the etching treatment.

[0129] Reference Example 6 To 85% phosphoric acid, 5.50 wt % of a hydrolyzate of 3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) as a first etching inhibitor, 0.25 wt % of tetraethyl orthosilicate as a second etching inhibitor, and 0.20 wt % of succinic acid dihydrazide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a precipitation inhibitor were added and dissolved, and a predetermined amount of silicon nitride was pre-dissolved in the solution, and the concentration of Si derived from the silicon nitride in the solution was adjusted to 300 ppm to prepare the etching solution composition of Reference Example 6. This etching solution composition of Reference Example 6 was heated before use in the etching treatment.

[0130] <Etching Test> Next, test conditions, measurement methods, etc. in the etching tests (etching treatments) carried out using the etching solution compositions of Examples 1 to 11 and Comparative Examples 1 to 23, and the etching solution compositions of Reference Examples 1 to 6 will be described.

[0131] [Test Conditions] Test pieces made of silicon nitride (silicon nitride film) and test pieces made of silicon oxide (silicon oxide film) were prepared as etching targets. The size of each test piece was a square of 1.5 cm x 1.5 cm. The etching treatment time (t) was 20 minutes for the silicon nitride film and 60 minutes for the silicon oxide film. The etching treatment temperature was 158°C.

[0132] [Method for measuring silicon nitride-derived silicon concentration] The silicon concentration [Si 1a] of the etching solution composition and the silicon concentration [Si 1b] of the fatigue solution in which silicon nitride was dissolved in the etching solution composition were measured, and the silicon nitride-derived silicon concentration [Si 1] was calculated using the following formula (1): [Si 1] = [Si 1b] - [Si 1a] (1) The silicon concentration [Si 1a] of the etching solution composition is derived from the etching inhibitor contained in the etching solution composition. The Si concentration in the solution was measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES) using a high-resolution ICP atomic emission spectrometer (product name "PS3520", manufactured by Hitachi High-Tech Science Corporation).

[0133] [Method for measuring etching rate] The thickness of the silicon nitride film before etching treatment [T １ａ ], the thickness of the silicon nitride film after etching [T １ｂ ] was measured, and the etching rate of silicon nitride [R １ ] was obtained. １ ] = [T １ａ ]-[T １ｂ ] / t (20 min) ... (2) Similarly, the film thickness of the silicon oxide film before etching [T ２ａ ], the thickness of the silicon oxide film after etching [T ２ｂ ] was measured, and the etching rate of silicon oxide [R ２ ] was obtained. ２ ] = [T ２ａ ]-[T ２ｂ ] / t (60 min) ... (3) The etching rate of silicon nitride [R １ ] and the etching rate of silicon oxide [R ２ ] is taken as the selectivity ratio [R １ / R ２ The film thickness was measured using an optical interference film thickness monitor (product name "Ava Thinfilm", manufactured by Avantes).

[0134] [Evaluation of Silica Deposition on the Surface of Silicon Oxide Film] The thickness of the silicon oxide film before etching [T ２ａ ] and the thickness of the silicon oxide film after etching [T ２ｂ ] and the difference ([T ２ａ ]-[T ２ｂ If the film thickness after etching has increased (if the difference is a negative value), it can be determined that silica has precipitated on the surface of silicon oxide.

[0135] [Etching Test Method] In order to stably carry out the etching test (etching treatment), a separable quartz flask was fitted with a cap with a mouth, and a reflux tube and a thermometer for temperature control were attached to prevent changes in the concentration of the etching solution composition, and the etching treatment was carried out.

[0136] [Heating Method] The reflux tube attached to the quartz flask was removed, the liquid temperature was raised to a boiling state (about 165°C), and the liquid was heated for 3 hours while maintaining the boiling state. This heating treatment was carried out to confirm whether the fluorine compound would volatilize. Note that, since evaporation of water by the heating treatment increases the phosphoric acid concentration and the boiling point, to prevent this, pure water was added each time to adjust the concentration and liquid temperature.

[0137] The formulations of the etching solution compositions according to Examples 1 to 11 are shown in Table 1, the formulations of the etching solution compositions according to Comparative Examples 1 to 13 are shown in Table 2, the formulations of the etching solution compositions according to Comparative Examples 14 to 23 are shown in Table 3, and the formulations of the etching solutions according to Reference Examples 1 to 6 are shown in Table 4. The chemical structural formula (2) shown in the column for second etching inhibitor is the siloxane compound shown above. Tables 1 to 4 also show the results of etching tests carried out using each etching solution composition and etching solution.

[0138]

[0139]

[0140]

[0141]

[0142] From the results of the above etching test, the following new findings were obtained regarding the etching composition according to the present invention.

[0143] The etching solution compositions of Examples 1 to 11, which contained a fluorine compound and a volatilization inhibitor, showed almost no difference in the etching rate of silicon nitride compared to Comparative Examples 1, 3, 5, and 7, which were not subjected to heat treatment (volatilization of the fluorine compound). The etching rates of silicon nitride were lower in Comparative Examples 2, 4, 6, and 8, which were subjected to heat treatment (volatilization of the fluorine compound), compared to Comparative Examples 1, 3, 5, and 7, which were not subjected to heat treatment (volatilization of the fluorine compound).

[0144] The results of the above etching test showed that the etching solution compositions (the present invention) according to Examples 1 to 11, in which a fluorine compound is used in combination with a volatilization inhibitor, increase the etching rate of silicon nitride by the fluorine compound while the volatilization inhibitor suppresses the volatilization of the fluorine compound. Therefore, even if the Si concentration in the etching solution composition increases, the etching rate of silicon nitride is maintained at a high level, making it possible to carry out etching treatment stably.

[0145] The etching solution composition according to the present invention is particularly useful in the industrial production of semiconductor elements having a three-dimensional structure, but can also be used in the industrial production of conventional semiconductor elements.

Claims

1. An inorganic acid-based etching solution composition for selectively etching silicon nitride from a semiconductor containing silicon nitride and silicon oxide, comprising: (a) a fluorine compound that increases the etching rate of silicon nitride; and (b) a volatilization inhibitor that suppresses the volatilization of the fluorine compound.

2. The etching solution composition according to claim 1, wherein the fluorine compound comprises an ionic compound whose counter anion is fluorine.

3. The etching solution composition according to claim 1, wherein the fluorine compound comprises at least one selected from the group consisting of ammonium hexafluorophosphate, tetrafluoroboric acid, 1-ethyl-3-methylimidazolium hexafluorophosphate, tetramethylammonium hexafluorophosphate, tetraethylphosphonium hexafluorophosphate, and 1-butyl-1-methylpyrrolidinium hexafluorophosphate.

4. The etching solution composition according to claim 1, wherein the volatilization inhibitor is a compound or salt having at least one skeleton selected from the group consisting of an imidazolium skeleton, a pyrrolidinium skeleton, a piperidinium skeleton, a morphonium skeleton, a pyridinium skeleton, a quaternary phosphonium skeleton, and a quaternary ammonium skeleton, and the compound or salt does not contain a fluorine atom.

5. The etching solution composition according to claim 1, wherein the volatilization inhibitor is imidazole, tetrabutylphosphonium bromide, tetrakis(hydroxymethyl)phosphonium sulfate, tetrabutylammonium bromide, or 1-ethyl-1-methylpyrrolidinium bromide.

6. The etching solution composition according to any one of claims 1 to 5, further comprising: (c) an etching inhibitor that inhibits etching of silicon oxide; and (d) a deposition inhibitor that inhibits deposition of silica on the surface of silicon oxide.

7. The etching solution composition according to claim 6, wherein the etching inhibitor comprises a first etching inhibitor having, in its molecular structure, three or less alkoxy groups, hydroxyl groups, and / or functional groups that can be precursors to hydroxyl groups, and a second etching inhibitor having, in its molecular structure, four or more alkoxy groups, hydroxyl groups, and / or functional groups that can be precursors to hydroxyl groups.

8. The etching solution composition according to claim 7, wherein the first etching inhibitor is a silane compound having an amino group.

9. The etching composition according to claim 8, wherein the silane compound having an amino group includes 3-aminopropyltrimethoxysilane and / or 3-aminopropyltriethoxysilane.

10. The second etching inhibitor has the following formula (I): The etching solution composition according to claim 7, wherein R in formula (I) is a compound having the chemical structure shown below: １ ~R ６ are substituents, at least four of which are at least one specific substituent selected from the group consisting of an alkoxy group, a hydroxyl group, and a halogen group, and the substituents other than the specific substituents are at least one substituent selected from the group consisting of an alkyl group, an aryl group, a carbonyl group, a carboxyl group, an amino group, an ethylenediamine group, and derivatives or composite groups of these substituents. X in formula (I) is "O" (oxygen atom) or "-" (single bond). n in formula (I) is an integer of 0 to 6.

11. The second etching inhibitor is represented by the following formula (2): The etching solution composition according to claim 7, wherein the compound has the chemical structure shown below.

12. The etching composition according to claim 6, wherein the deposition inhibitor comprises a hydrazide.

13. The etching composition according to claim 12, wherein the hydrazides include at least one selected from the group consisting of adipic acid dihydrazide, succinic acid dihydrazide, and azelaic acid dihydrazide.

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