Composition and composition-containing container

Abstract

A composition contains octafluorocyclobutane and at least one of iodine and an iodine-containing perfluoroalkyl compound, and the content of at least one of the iodine and the iodine-containing perfluoroalkyl compound is 1,000 molar ppm or less with respect to the total molar amount of the composition.

Description

Composition and composition-containing container

[0001] The present disclosure relates to compositions and containers containing the compositions.

[0002] Etching is a method for removing unnecessary thin film portions on a semiconductor substrate in the semiconductor manufacturing process, thereby processing the surface into a desired shape. For example, Patent Document 1 discloses etching an interlayer insulating film on a semiconductor substrate using octafluorocyclobutane.

[0003] Japanese Patent Application Laid-Open No. 2001-267294

[0004] However, according to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, octafluorocyclobutane has a high global warming potential (GWP) of 9,540, and therefore poses a significant environmental burden if it leaks. On the other hand, octafluorocyclobutane is a colorless and odorless gas at 25°C and 1 atmosphere, making it difficult to detect a leak. Furthermore, gas flavorings or colorants typically used to detect leaks tend to reduce etching performance. The present disclosure has been made in light of the above, and relates to the provision of a composition and a container containing the composition that have excellent etching performance and are easy to detect a leak.

[0005] The present disclosure includes the following aspects: <1> A composition comprising octafluorocyclobutane and at least one of iodine and an iodine-containing perfluoroalkyl compound, wherein the content of the at least one of the iodine and the iodine-containing perfluoroalkyl compound is 1,000 molar ppm or less relative to the total molar amount of the composition. <2> The composition according to <1>, wherein the content of the at least one of the iodine and the iodine-containing perfluoroalkyl compound is 10 molar ppm or more relative to the total molar amount of the composition. <3> The composition according to <1> or <2>, wherein the iodine-containing perfluoroalkyl compound is at least one selected from the group consisting of 1,2-diiodoperfluoroethane, 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1-iodoperfluoroethane, 1-iodoperfluoropropane, 1-iodoperfluorobutane, 2-iodoperfluoropropane, 1-iodoperfluoropentane, 1-iodoperfluorohexane, 1-iodoperfluoroheptane, and 1-iodoperfluorooctane. <4> The composition according to any one of <1> to <3>, wherein the content of the iodine-containing perfluoroalkyl compound is 500 mole ppm or less based on the total molar amount of the composition. <5> The composition according to any one of <1> to <4>, further comprising water. <6> The composition according to <5>, wherein the water content is 1,000 molar ppm or less based on the total molar amount of the composition. <7> The composition according to any one of <1> to <6>, which is used for etching, refrigerant, heat transfer medium, foaming agent, or resin monomer. <8> A composition-containing container comprising a container and the composition according to any one of <1> to <7> filled in the container. <9> The composition-containing container according to <8>, wherein the container is made of stainless steel, chromium molybdenum steel, or carbon steel.

[0006] According to the present disclosure, a composition and a container containing the composition are provided that have excellent etching performance and are easy to detect leaks.

[0007] An embodiment of the present disclosure will be described in detail below. However, the present disclosure is not limited to the following embodiment. In the following disclosure, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present disclosure.

[0008] In the present disclosure, when a numerical range is indicated using "to", the numerical values ​​before and after "to" are included as the lower and upper limits, respectively. In the present disclosure, when a numerical range is indicated in a stepped manner, the upper or lower limit stated in one numerical range may be replaced with the upper or lower limit of another stepped numerical range. Furthermore, in the numerical ranges described in the present disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. The upper and lower limit values ​​may be arbitrarily combined to form a numerical range, as long as no contradiction occurs. In the present disclosure, when the composition contains multiple substances corresponding to each component, the content or amount of each component refers to the total content or amount of the multiple substances present in the composition, unless otherwise specified. In the present disclosure, when multiple elements are listed using "or", multiple elements may be selected in combination, unless otherwise specified, as long as no technical contradiction occurs. In the present disclosure, when an element is expressed in the singular, this does not exclude the presence of multiple elements, unless otherwise specified, as long as no technical contradiction occurs. In the present disclosure, multiple exemplary aspects described separately may be combined with each other to form a new aspect, unless they contradict each other.

[0009] <Composition> The composition of the present disclosure contains octafluorocyclobutane and at least one of iodine and an iodine-containing perfluoroalkyl compound, and the content of the at least one of iodine and the iodine-containing perfluoroalkyl compound is 1,000 mole ppm or less based on the total molar amount of the composition.

[0010] The composition of the present disclosure has excellent etching performance and is a composition in which leakage is easily detected. Since the iodine and iodine-containing perfluoroalkyl compound contained in the composition of the present disclosure are both light brown to brown, leakage of the composition can be visually confirmed. On the other hand, iodine and iodine-containing perfluoroalkyl compounds tend to reduce etching performance. Therefore, the composition of the present disclosure has an iodine content of at least one of the iodine and the iodine-containing perfluoroalkyl compound below a certain level so that the composition has excellent etching performance and leakage is easily detected. However, the present disclosure is not limited to the above mechanism.

[0011] <Octafluorocyclobutane> The composition of the present disclosure contains octafluorocyclobutane (hereinafter also referred to as "C-318"). From the viewpoint of making it easy to detect leakage, the content of C-318 is preferably less than 100.000 mol%, more preferably 99.999 mol% or less, and even more preferably 99.990 mol% or less, based on the total molar amount of the composition of the present disclosure. From the viewpoint of etching performance, the content of C-318 is preferably 98.000 mol% or more, more preferably 99.000 mol% or more, even more preferably 99.900 mol% or more, particularly preferably 99.990 mol% or more, and most preferably 99.999 mol% or more, based on the total molar amount of the composition of the present disclosure.

[0012] In the present disclosure, the content of C-318 in a composition is measured using a gas chromatograph under the following measurement conditions: Instrument body: 7890GC (manufactured by Agilent Technologies, Inc.) Detector: Flame ionization detector (FID) Column: DB-1301 (manufactured by Agilent Technologies, Inc.)

[0013] There are no particular limitations on how C-318 can be obtained, and it may be commercially available C-318 or C-318 produced by a known method.

[0014] Specifically, an example of a method for producing C-318 is the method described in International Publication No. 2023 / 282241. According to this method, a mixture of C-318 and octafluorobutene is obtained as a by-product in the process of producing hexafluoropropylene from tetrafluoroethylene. Then, after producing C-318 by hydrogenating octafluorobutene, high-purity C-318 can be obtained by distilling the composition containing C-318 and octafluorobutane.

[0015] Another method for producing C-318 is described in Japanese Patent Laid-Open No. 2004-168753. According to this method, C-318 is obtained as a by-product in the step of producing α,ω-diiodoperfluoroalkane by reacting 1,2-diiodoperfluoroethane with tetrafluoroethylene.

[0016] Other methods for producing C-318 include the following: Specifically, 1,2-diiodoperfluoroethane is heated to 230°C and reacted for 10 hours, then cooled to 40°C, and the gas phase is recovered and rectified to obtain high-purity C-318.

[0017] <At least one of iodine and iodine-containing perfluoroalkyl compound> The composition of the present disclosure contains at least one of iodine and iodine-containing perfluoroalkyl compound.

[0018] The composition of the present disclosure may contain only either iodine or an iodine-containing perfluoroalkyl compound. Preferably, the composition of the present disclosure contains C-318 and iodine, but does not contain an iodine-containing perfluoroalkyl compound. The composition of the present disclosure may contain C-318 and an iodine-containing perfluoroalkyl compound, but does not contain iodine.

[0019] The composition of the present disclosure may contain both iodine and iodine-containing perfluoroalkyl compound.When the composition of the present disclosure contains both iodine and iodine-containing perfluoroalkyl compound, the molar ratio of iodine / iodine-containing perfluoroalkyl compound is not particularly limited, and from the viewpoint of easy detection of leakage, it is preferably 3 / 1 or more, more preferably 5 / 1 or more, and even more preferably 10 / 1 or more.From the viewpoint of corrosion inhibition, the molar ratio of iodine / iodine-containing perfluoroalkyl compound is preferably 10 / 1 or less, more preferably 5 / 1 or less, and even more preferably 3 / 1 or less.

[0020] In the composition of the present disclosure, the content of at least one of iodine and iodine-containing perfluoroalkyl compound is 1,000 mol ppm or less relative to the total molar amount of the composition.From the viewpoint of excellent etching performance, in the composition of the present disclosure, the content of at least one of iodine and iodine-containing perfluoroalkyl compound is preferably 900 mol ppm or less relative to the total molar amount of the composition, more preferably 700 mol ppm or less, and even more preferably 500 mol ppm or less.When the composition of the present disclosure contains both iodine and iodine-containing perfluoroalkyl compound, the total content of iodine and iodine-containing perfluoroalkyl compound in the composition is preferably 1,000 mol ppm or less, more preferably 900 mol ppm or less, more preferably 700 mol ppm or less, and particularly preferably 500 mol ppm or less.

[0021] From the viewpoint of easily noticing leakage, in the composition of the present disclosure, the content of at least one of iodine and iodine-containing perfluoroalkyl compound is preferably 10 mol ppm or more, more preferably 100 mol ppm or more, even more preferably 300 mol ppm or more, particularly preferably 500 mol ppm or more.When the composition of the present disclosure contains both iodine and iodine-containing perfluoroalkyl compound, the total content of iodine and iodine-containing perfluoroalkyl compound in the composition is preferably 10 mol ppm or more, more preferably 100 mol ppm or more, even more preferably 300 mol ppm or more, particularly preferably 500 mol ppm or more.

[0022] In the present disclosure, the total content of iodine and iodine-containing perfluoroalkyl compounds in the composition is determined from the sum of the content of iodine in the composition and the content of iodine-containing perfluoroalkyl compounds in the composition, as described below.

[0023] (Iodine) In the composition of the present disclosure, the content of iodine is preferably 1,000 mol ppm or less, more preferably 900 mol ppm or less, even more preferably 700 mol ppm or less, and particularly preferably 500 mol ppm or less, based on the total molar amount of the composition, from the viewpoint of etching performance and corrosion inhibition of a container filled with the composition. From the viewpoint of easily detecting leakage, the content of iodine is preferably 100 mol ppm or more, more preferably 300 mol ppm or more, and even more preferably 500 mol ppm or more, based on the total molar amount of the composition.

[0024] In the present disclosure, the iodine content in a composition is measured by ion chromatographic analysis of an absorbed solution obtained by absorbing a measurement sample into an aqueous sodium thiosulfate solution under the following measurement conditions: Measurement instrument: ICS-5000 (manufactured by Thermo Fisher Scientific) Column: AS11-HC (manufactured by Thermo Fisher Scientific)

[0025] (Iodine-containing perfluoroalkyl compound) In the present disclosure, an iodine-containing perfluoroalkyl compound refers to a perfluoroalkyl compound in which one or more hydrogen atoms have been substituted with an iodine atom.

[0026] The type and number of iodine-containing perfluoroalkyl compounds are not particularly limited. The number of types of iodine-containing perfluoroalkyl compounds contained in the composition of the present disclosure may be 0 or more, 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, 7 or more, or 10 or more. The number of types may be 10 or less, 7 or less, 5 or less, 4 or less, 3 or less, 2 or less, or 1 or less.

[0027] The iodine-containing perfluoroalkyl compound may be either linear or branched.

[0028] The molecular weight of the iodine-containing perfluoroalkyl compound may be 200 or more, 300 or more, or 400 or more, and from the viewpoint of ease of handling, it is preferably 200 or more. The molecular weight of the iodine-containing perfluoroalkyl compound may be 500 or less, 450 or less, or 400 or less, and from the viewpoint of easy detection of leakage, it is preferably 400 or less. That is, if the molecular weight of the iodine-containing perfluoroalkyl compound is too high, the boiling point becomes high and it becomes difficult to vaporize, which means that it is difficult to detect leakage.

[0029] The iodine-containing perfluoroalkyl compound is preferably at least one selected from the group consisting of 1,2-diiodoperfluoroethane, 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1-iodoperfluoroethane, 1-iodoperfluoropropane, 1-iodoperfluorobutane, 2-iodoperfluoropropane, 1-iodoperfluoropentane, 1-iodoperfluorohexane, 1-iodoperfluoroheptane, and 1-iodoperfluorooctane, more preferably at least one of 1,2-diiodoperfluoroethane and 1,4-diiodoperfluorobutane, and even more preferably 1,2-diiodoperfluoroethane. The iodine-containing perfluoroalkyl compound is preferably a diiodoperfluoroalkyl compound.

[0030] In the composition of the present disclosure, the content of the iodine-containing perfluoroalkyl compound is preferably 500 mol ppm or less, more preferably 300 mol ppm or less, and even more preferably 100 mol ppm or less, based on the total molar amount of the composition, from the viewpoint of etching performance and corrosion inhibition of the container in which the composition is filled. From the viewpoint of easily noticing leakage, the content of the iodine-containing perfluoroalkyl compound is preferably 10 mol ppm or more, more preferably 50 mol ppm or more, and even more preferably 100 mol ppm or more, based on the total molar amount of the composition.

[0031] In the present disclosure, the content of iodine-containing perfluoroalkyl compounds in a composition is measured using a gas chromatograph under the following measurement conditions. When multiple types of iodine-containing perfluoroalkyl compounds are present in the composition of the present disclosure, the content of iodine-containing perfluoroalkyl compounds refers to the total content of those multiple types of iodine-containing perfluoroalkyl compounds. Instrument body: 7890GC (manufactured by Agilent Technologies, Inc.) Detector: flame ionization detector (FID) Column: DB-1301 (manufactured by Agilent Technologies, Inc.)

[0032] <Water> The composition of the present disclosure may contain water.

[0033] In the composition of the present disclosure, the water content is preferably 1,000 mol ppm or less, more preferably 500 mol ppm or less, and even more preferably 200 mol ppm or less, based on the total molar amount of the composition, from the viewpoint of etching performance. The water content is preferably 10 mol ppm or more, more preferably 50 mol ppm or more, and even more preferably 100 mol ppm or more, based on the total molar amount of the composition.

[0034] In the present disclosure, the water content in the composition is determined from the moisture content measured using a dew point meter DewStar S-2 (manufactured by Shin-ei Technology Co., Ltd.).

[0035] The composition of the present disclosure may contain additives, such as known leak detection substances other than nitrogen, oxygen, argon, carbon dioxide, fluorocarbons, tetrafluoroethylene, iodine, or iodine-containing perfluoroalkyl compounds, stabilizers, or polymerization inhibitors.

[0036] The content of nitrogen, oxygen, argon, carbon dioxide, fluorocarbon, or tetrafluoroethylene in the composition of the present disclosure is not particularly limited. The content of nitrogen, oxygen, argon, carbon dioxide, fluorocarbon, or tetrafluoroethylene may be 50 mol ppm or more, 100 mol ppm or more, or 200 mol ppm or more, respectively, relative to the total molar amount of the composition. The content of nitrogen, oxygen, argon, carbon dioxide, fluorocarbon, or tetrafluoroethylene may be 500 mol ppm or less, 250 mol ppm or less, or 100 mol ppm or less, respectively, relative to the total molar amount of the composition.

[0037] Leak detection materials include ultraviolet fluorescent dyes, odorous gases, and odor masking agents.

[0038] Examples of ultraviolet fluorescent dyes include conventionally known ultraviolet fluorescent dyes such as those described in U.S. Pat. No. 4,249,412, JP-A-10-502737, JP-A-2007-511645, JP-A-2008-500437, and JP-A-2008-531836.

[0039] Examples of odor masking agents include conventionally known fragrances such as those described in JP-A Nos. 2008-500437 and 2008-531836.

[0040] When a leak detection substance is used, a solubilizing agent may be used to improve the solubility of the leak detection substance in the composition. Examples of solubilizing agents include those described in JP-A Nos. 2007-511645, 2008-500437, and 2008-531836.

[0041] The content of the leak detection substance may be within a range that does not significantly reduce the effects of the present disclosure, and is preferably 2% by mass or less, and more preferably 0.5% by mass or less, relative to 100% by mass of the composition.

[0042] The stabilizer is a component that improves the thermal and oxidative stability of the composition. Examples of the stabilizer include conventionally known stabilizers, such as oxidation resistance improvers, heat resistance improvers, and metal deactivators.

[0043] Examples of oxidation resistance improvers and heat resistance improvers include N,N'-diphenylphenylenediamine, p-octyldiphenylamine, p,p'-dioctyldiphenylamine, N-phenyl-1-naphthylamine, N-phenyl-2-naphthylamine, N-(p-dodecyl)phenyl-2-naphthylamine, di-1-naphthylamine, di-2-naphthylamine, N-alkylphenothiazine, 6-(t-butyl)phenol, 2,6-di-(t-butyl)phenol, 4-methyl-2,6-di-(t-butyl)phenol, and 4,4'-methylenebis(2,6-di-t-butylphenol). The oxidation resistance improvers and heat resistance improvers may be used alone or in combination of two or more.

[0044] Examples of metal deactivators include imidazole, benzimidazole, 2-mercaptobenzthiazole, 2,5-dimethylcaptothiadiazole, salicylidyne-propylenediamine, pyrazole, benzotriazole, tolutriazole, 2-methylbenzamidazole, 3,5-dimethylpyrazole, methylenebis-benzotriazole, organic acids or esters thereof, primary, secondary or tertiary aliphatic amines, amine salts of organic or inorganic acids, heterocyclic nitrogen-containing compounds, amine salts of alkyl acid phosphates or derivatives thereof, and the like.

[0045] The content of the stabilizer may be within a range that does not significantly reduce the effects of the present disclosure, and is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% by mass, even more preferably 0.1 to 2% by mass, still more preferably 0.25 to 1.5% by mass, and particularly preferably 0.5 to 1% by mass, relative to 100% by mass of the composition.

[0046] The polymerization inhibitor is not particularly limited and can be appropriately selected from commonly used polymerization inhibitors. The polymerization inhibitor may be used alone or in combination of two or more kinds.

[0047] Examples of the polymerization inhibitor include 4-methoxy-1-naphthol, hydroquinone, hydroquinone methyl ether, dimethyl-tert-butylphenol, 2,6-di-tert-butyl-p-cresol, and benzotriazole.

[0048] The content of the polymerization inhibitor is not particularly limited, and is preferably 0.01 to 5 mass %, more preferably 0.05 to 3 mass %, even more preferably 0.1 to 2 mass %, still more preferably 0.25 to 1.5 mass %, and particularly preferably 0.5 to 1 mass %, relative to the total amount of the composition.

[0049] <Applications> The composition of the present disclosure can be used in a variety of applications, including etching for forming fine structures of semiconductors, liquid crystals, etc., as well as refrigerants, heat transfer media, foaming agents, resin monomers, etc. ... ２ It may also be used for etching.

[0050] <Method for preparing the composition> The method for preparing the composition of the present disclosure is not particularly limited, and the composition can be prepared by a known method. The composition of the present disclosure may be obtained by mixing C-318 with at least one of iodine and an iodine-containing perfluoroalkyl compound, etc.

[0051] Alternatively, the composition of the present disclosure can be obtained by heating 1,2-diiodoperfluoroethane to 200 to 300° C., reacting for 1 to 10 hours or more, cooling to 20 to 50° C., recovering the gas phase, and rectifying it. More specifically, the composition of the present disclosure can be obtained by heating 1,2-diiodoperfluoroethane to 230° C., reacting for 10 hours, cooling to 40° C., recovering the gas phase, and rectifying it.

[0052] (Dehydration) The composition of the present disclosure may be dehydrated. Dehydration may be performed by a known method. Examples of methods for dehydrating the composition include a method of reacting the composition with water or a method of using a dehydrating agent (water adsorbent) in the composition. Dehydration may also be performed by azeotropic dehydration, distillation, or membrane separation.

[0053] In the method of reacting with water, metallic potassium, metallic sodium, lithium aluminum hydride, calcium hydride, diphosphorus pentoxide, calcium oxide, magnesium oxide, potassium hydroxide, sodium hydroxide, concentrated sulfuric acid, calcium sulfate, magnesium sulfate, sodium sulfate, calcium chloride, zinc chloride, potassium carbonate, or the like may be used.

[0054] As a method using a dehydrating agent, zeolite, activated carbon, activated alumina, silica gel, or the like may be used. Specific dehydration methods include contacting the dehydrating agent with the composition to dehydrate. For example, the composition of the present disclosure in a gaseous or liquid state may be passed through a dehydration tower filled with the dehydrating agent. One type of dehydrating agent may be used alone, or two or more types may be used in combination.

[0055] Among the above methods, the method using zeolite is preferred as it has little effect on the composition and allows for easy dehydration. Examples of zeolite include synthetic zeolites having the chemical compositions shown in the following chemical formulas (Z1) and (Z2). ｘ Na ｙ [(AlO ２ ) １２ (SiO ２ ) １２ ]・27H ２ O (Z1) (In formula (Z1), x+y=12, and x:y=4:6 to 8:2) K ｘ Na ｙ [(AlO ２ ) ８６ (SiO ２ ) １０６ ]・276H ２ O (Z2) (In formula (Z2), x + y = 86, and x:y = 4:6 to 8:2.) There are several grades of zeolite depending on the type of raw zeolite, such as zeolite 3A, 4A, and 5A. Zeolite 3A, 4A, and 5A are synthetic zeolites with pore diameters of 0.25 to 0.45 nm. Commercially available products include molecular sieve 3A (MS-3A), molecular sieve 4A (MS-4A), and molecular sieve 5A (MS-5A) (all manufactured by Union Showa Co., Ltd.), with MS-3A or MS-4A being preferred. A commercially available X-type zeolite is molecular sieve 13X, which may be used in combination with zeolite 3A, 4A, or 5A. The pore diameter of a zeolite can be measured by a constant volume gas adsorption method. The adsorption gas used in the constant volume gas adsorption method is N ２ , CO ２ , C.H. ４ , H ２Alternatively, Ar and the like can be mentioned.

[0056] Methods for drying a composition using a molecular sieve include placing the composition and molecular sieve in a sealed container and allowing it to stand, or filling a column with molecular sieve and passing or circulating the composition through it, etc. As an example of the method of allowing it to stand, 1 to 50 g, preferably 3 to 30 g, of molecular sieve per kg of composition is placed in a container that is difficult for external air to pass through, sealed, and allowed to stand for 1 to 5 days to dehydrate.

[0057] <Composition-Containing Container> A composition-containing container of the present disclosure has a container and the composition of the present disclosure filled in the container.

[0058] The material of the container is preferably stainless steel, chromium molybdenum steel, or carbon steel, more preferably stainless steel from the viewpoint of corrosion resistance, and more preferably carbon steel from the viewpoint of cost.

[0059] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to the following examples as long as it does not deviate from the gist of the disclosure. Examples 1 to 6 are examples, and Examples 7 and 8 are comparative examples.

[0060] (Preparation of Compositions) Each of the compositions of Examples 1 to 8 was prepared by the following method using C-318 (manufactured by Resonac Corporation), 1,2-diiodotetrafluoroethane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as a 1,2-diiodotetrafluoroalkane, iodine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and water.

[0061] Iodine was charged into a 100 mL pressure-resistant glass cylinder capable of withstanding a pressure of 1.0 MPaG or more, and the cylinder was placed under reduced pressure. 1,2-diiodotetrafluoroethane and water were further charged into the pressure-resistant glass cylinder in this order, and the contents of iodine, 1,2-diiodotetrafluoroethane, and water in the composition were prepared so that their respective contents (unit: mol ppm) in the composition were as shown in Table 1 below. The pressure-resistant glass cylinder was then cooled to -40°C, and C-318 was further charged until the total molar amount of the composition reached 100%, and the mixture was then returned to 25°C and mixed.

[0062] (Etching performance) SiO2 with a thickness of about 1 μm on a Si substrate２ A semiconductor substrate having a resist pattern with a hole diameter of 0.21 μm thereon was prepared. The semiconductor substrate was etched using each of the compositions of Examples 1 to 8 listed in Table 1 as an etching gas. The etching conditions were an inductively coupled plasma (ICP) method with a discharge power of 600 W, a bias power of 200 W, a gas pressure of 3 mTorr (0.399 Pa), and an electron density of 8×10 １０ ~2 x 10 １１ cm －３ The electron temperature was set to 5 to 7 eV.

[0063] Etching performance is SiO ２ The etching rate was evaluated according to the following criteria. The results are shown in Table 1. ２ The higher the etching rate, the higher the production efficiency, and therefore the better the etching performance. ２ Etching rate is more than 5.5 and 7.0 μm / min or less. B: SiO ２ Etching rate is more than 4.0 and 5.5 μm / min or less. C: SiO ２ The etching rate is more than 2.5 and not more than 4.0 μm / min.

[0064] (Color) The color of each composition of Examples 1 to 8 was visually confirmed. The results are shown in Table 1. When the composition is colored, it becomes easier to check for leakage of the composition.

[0065] (Storage Stability) The storage stability of the metals used in the containers was confirmed assuming storage in a container of each of the compositions in Examples 1 to 8 below. The test method involved preparing a colorless pressure-resistant glass cylinder so that the contents could be seen, placing various metal pieces shown in Table 1 below in the cylinder, and then filling it with each of the compositions under reduced pressure, followed by leaving it to stand for 30 days.

[0066] - Appearance - The appearance of the metal pieces that had been left to stand was visually inspected according to the following criteria. A and B are within the range acceptable for practical use. The results are shown in Table 1. A: Almost no staining or rust was observed on the metal surface. B: The metal surface was partially stained brown or purple and rusted. C: The metal surface was almost entirely stained brown or purple and rusted.

[0067] - Degree of corrosion - The metal pieces were left to rest in the cylinder for 30 days, after which the mass of the metal pieces was measured. The change in mass of the metal pieces before and after placing them in the cylinder was converted into the annual erosion depth (mm / year) with reference to JIS Z 2383:1998 (ISO 9226:1992). The erosion depth obtained was used to evaluate the degree of erosion of the metal pieces according to the following criteria. The results are shown in Table 1. A: Erosion depth less than 0.005 mm / year. B: Erosion depth 0.005 to less than 0.02 mm / year. C: Erosion depth 0.02 mm / year or more.

[0068]

[0069] From the above, the compositions of Examples 1 to 6 were excellent in etching performance and were compositions in which leakage was easily detected. Furthermore, the compositions of Examples 1 to 6 also had excellent storage stability for metals.

[0070] The disclosure of Japanese Patent Application No. 2024-013759, filed on January 31, 2024, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

[0071] The composition of the present disclosure has excellent etching performance and is easy to detect leakage. The composition of the present disclosure can be used as an etching gas in the semiconductor manufacturing process when processing a semiconductor substrate into a desired surface shape by removing unnecessary thin film portions on the substrate.

Claims

1. A composition comprising octafluorocyclobutane and at least one of iodine and an iodine-containing perfluoroalkyl compound, wherein the content of the at least one of iodine and the iodine-containing perfluoroalkyl compound is 1,000 molar ppm or less based on the total molar amount of the composition.

2. The composition according to claim 1, wherein the content of at least one of the iodine and the iodine-containing perfluoroalkyl compound is 10 mole ppm or more based on the total molar amount of the composition.

3. The composition according to claim 1 or 2, wherein the iodine-containing perfluoroalkyl compound is at least one selected from the group consisting of 1,2-diiodoperfluoroethane, 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1-iodoperfluoroethane, 1-iodoperfluoropropane, 1-iodoperfluorobutane, 2-iodoperfluoropropane, 1-iodoperfluoropentane, 1-iodoperfluorohexane, 1-iodoperfluoroheptane, and 1-iodoperfluorooctane.

4. The composition according to claim 1 or 2, wherein the content of the iodine-containing perfluoroalkyl compound is 500 molar ppm or less based on the total molar amount of the composition.

5. The composition of claim 1 or 2, further comprising water.

6. The composition according to claim 5, wherein the water content is 1,000 molar ppm or less based on the total molar amount of the composition.

7. The composition according to claim 1 or 2, which is used for etching, refrigerant, heat transfer medium, foaming agent, or resin monomer.

8. A composition-containing container comprising a container and the composition according to claim 1 or 2 filled in the container.

9. The composition-containing container according to claim 8, wherein the container is made of stainless steel, chromium molybdenum steel, or carbon steel.

Images