KR20240027880A - Chemical solution and chemical solution container - Google Patents

Abstract

The present invention provides a chemical solution in which metal residue defects are unlikely to occur when brought into contact with a silicon substrate, and a chemical solution receptor. The chemical solution of the present invention is a chemical solution containing an organic solvent and a metal component. The metal component contains silver ions, and the content of silver ions is 0.0010 to 1.0 ppt by mass based on the total mass of the chemical solution.

Description

Chemical solution, chemical receptor {CHEMICAL SOLUTION AND CHEMICAL SOLUTION CONTAINER}

The present invention relates to a chemical solution and a chemical solution receptor.

When manufacturing a semiconductor device by a wiring formation process including photolithography, a prewet solution, a resist solution (composition for forming a resist film), a developer, a rinse solution, a stripper, a chemical mechanical polishing (CMP) slurry, And as a cleaning solution after CMP, etc., or as a dilution thereof, a chemical solution containing water and/or an organic solvent is used.

Recently, with the advancement of photolithography technology, patterns are being refined. As a technique for pattern miniaturization, pattern formation using ultraviolet rays, KrF excimer lasers, ArF excimer lasers, and EUV (extreme ultraviolet rays) as exposure light sources has been attempted.

As the patterns to be formed are refined, additional defect suppression properties are required for the chemical solutions used in this process.

As a chemical solution used in conventional pattern formation, Patent Document 1 describes “A method for producing an organic treatment liquid for patterning a chemically amplified resist film capable of reducing the generation of particles in pattern formation technology (paragraph [0010]).” It has been disclosed.

Patent Document 1: Japanese Patent Publication No. 2015-084122

Meanwhile, in recent years, there has been a demand for a chemical solution in which metal residue defects are less likely to occur on the silicon substrate when the chemical solution is brought into contact with the silicon substrate.

The object of the present invention is to provide a chemical solution in which metal residue defects are unlikely to occur when brought into contact with a silicon substrate.

Another object of the present invention is to provide a chemical receptor.

As a result of intensive studies to solve the above problem, the present inventors have found that the above problem can be solved by the following configuration.

(1) A chemical solution containing an organic solvent and a metal component,

The metal component contains silver ions,

A chemical solution with a silver ion content of 0.0010 to 1.0 mass ppt, based on the total mass of the chemical solution.

(2) The chemical solution described in (1), wherein the content of the metal component is 10.0 to 500 ppt by mass based on the total mass of the chemical solution.

(3) the metal component contains silver oxide particles,

The chemical solution according to (2), wherein the mass ratio 1 of the content of silver oxide particles to the content of silver ions is 0.00000010 to 0.1.

(4) The chemical solution according to (3), wherein the content of silver oxide particles is 0.00010 to 5.0% by mass relative to the content of the silver component in the metal component.

(5) the metal component contains titanium oxide particles and titanium ions;

The chemical solution according to (3) or (4), where the mass ratio of the content of titanium oxide particles to the content of titanium ions of 2 and the mass ratio of 1 satisfy the relationship of the following formula (A).

Equation (A) Mass ratio 2>Mass ratio 1

(6) The chemical solution described in (5), wherein the ratio of the content of titanium oxide particles to the content of silver oxide particles is 10 ² to 10 ¹⁰ .

(7) The chemical solution according to (5) or (6), where the number of titanium oxide particles is 10 ² to 10 ¹⁰ .

(8) The chemical solution according to any one of (5) to (7), wherein the content of titanium oxide particles is 5% by mass or more and less than 98% by mass with respect to the content of the titanium component in the metal component.

(9) The chemical solution according to any one of (5) to (8), wherein the proportion of particles with a particle size of 0.5 to 17 nm among titanium oxide particles is 40% by mass or more and less than 99% by mass.

(10) The metal component contains copper oxide particles and copper ions,

The chemical solution according to any one of (3) to (9), wherein the mass ratio 3 of the content of copper oxide particles to the content of copper ions and the mass ratio 1 satisfy the relationship of the following formula (B).

Equation (B) Mass ratio 3>Mass ratio 1

(11) The metal component contains iron oxide particles and iron ions,

The chemical solution according to any one of (3) to (9), wherein the mass ratio of the iron oxide particle content to the iron ion content of 4 and the mass ratio of 1 satisfy the relationship of the following formula (C).

Equation (C) Mass ratio 4>Mass ratio 1

(12) The metal component contains platinum ions,

The chemical solution according to any one of (1) to (11), wherein the platinum ion content is 0.000010 to 1.0 mass ppt based on the total mass of the chemical solution.

(13) The metal component contains gold ions,

The chemical solution according to any one of (1) to (12), wherein the gold ion content is 0.00010 to 1.0 mass ppt based on the total mass of the chemical solution.

(14) contains more organic impurities,

The chemical solution according to any one of (1) to (13), wherein the content of organic impurities is 1000 to 100000 ppt by mass based on the total mass of the chemical solution.

(15) The chemical solution according to any one of (1) to (14), wherein the water content relative to the total mass of the chemical solution is 500 ppb by mass or less.

(16) Organic solvents include propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, cyclohexanone, ethyl lactate, propylene carbonate, isopropanol, 4-methyl-2-pentanol, butyl acetate. , propylene glycol monoethyl ether, propylene glycol monopropyl ether, methyl methoxypropionate, cyclopentanone, γ-butyrolactone, diisoamyl ether, isoamyl acetate, dimethyl sulfoxide, N -Methylpyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol, ethylene carbonate, sulfolane, cycloheptanone, 2-heptanone, butyl butyrate, isobutyrate The chemical solution according to any one of (1) to (15), containing at least one member selected from the group consisting of isobutyl sorbate, isoamyl ether, and undecane.

(17) A chemical liquid receptor containing a container and the chemical liquid according to any one of (1) to (16) contained in the container.

According to the present invention, it is possible to provide a chemical solution in which metal residue defects are unlikely to occur when brought into contact with a silicon substrate.

Additionally, according to the present invention, a chemical solution receptor can be provided.

Hereinafter, the present invention will be described in detail.

The description of the structural requirements described below may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

In addition, in this specification, the numerical range indicated using "~" means a range that includes the numerical values written before and after "~" as the lower limit and upper limit.

Additionally, in the present invention, “ppm” means “parts-per-million (10 ^-6 )”, “ppb” means “parts-per-billion (10 ^-9 )”, and “ppt” means “parts-per-billion (10 -9)”. means "parts-per-trillion(10 ^-12 )", and "ppq" means "parts-per-quadrillion(10 ^-15 )".

In addition, in the notation of groups (atomic groups) in the present invention, notation that does not describe substitution or unsubstitution refers to groups that contain a substituent as well as groups that do not have a substituent, to the extent that they do not impair the effect of the present invention. Includes prayer. For example, “hydrocarbon group” includes not only a hydrocarbon group without a substituent (unsubstituted hydrocarbon group) but also a hydrocarbon group containing a substituent (substituted hydrocarbon group). This point has the same meaning for each compound.

In addition, “radiation” in the present invention means, for example, deep ultraviolet rays, extreme ultraviolet (EUV), X-rays, or electron beams. Additionally, in the present invention, “light” means actinic rays or radiation. In the present invention, “exposure”, unless otherwise specified, includes not only exposure with deep ultraviolet rays, X-rays, or EUV, but also drawing with particle beams such as electron beams or ion beams.

Although the mechanism by which the above problem is solved by the chemical solution of the present invention is not necessarily clear, the present inventor speculates about the mechanism as follows. In addition, the following mechanism is speculation, and even if the effect of the present invention is obtained through a different mechanism, it is included in the scope of the present invention.

The present inventors discovered that when the chemical solution contains silver ions, the ease of occurrence of metal residue defects (residue derived from metal components) on the silicon substrate varies depending on the content. More specifically, when the amount of silver ions exceeds a predetermined value, since many silver ions exist, silver ions are reduced on the silicon substrate, a large amount of silver particles adhere to the silicon substrate, and metal residue defects occur. I think they are doing it. On the other hand, when the amount of silver ions is less than a predetermined value, the frequency of collisions with organic substances or other ions decreases, and as a result, the possibility of reaction with the silicon substrate increases, and it is believed that metal residue defects occur as a result. On the other hand, when the amount of silver ions is within a predetermined range, the frequency of collisions with organic substances or other ions increases, resulting in various complexes, and the amount of silver ions used in the reduction reaction on the silicon substrate decreases, resulting in metal It is thought that residual defects are less likely to occur.

The chemical solution of the present invention is a chemical solution containing an organic solvent and a metal component. The metal component contains silver ions, and the content of silver ions is 0.0010 to 1.0 ppt by mass based on the total mass of the chemical solution.

Hereinafter, the components contained in the chemical solution of the present invention will be described in detail.

<Organic solvent>

The chemical solution (hereinafter also simply referred to as “chemical solution”) of the present invention contains an organic solvent.

In this specification, the organic solvent refers to a liquid organic compound contained in a content exceeding 10,000 ppm by mass per component, relative to the total mass of the chemical solution. That is, in this specification, the liquid organic compound contained in excess of 10000 ppm by mass relative to the total mass of the chemical liquid corresponds to the organic solvent.

In addition, in this specification, liquid phase means liquid at 25°C and atmospheric pressure.

The content of the organic solvent in the chemical solution is not particularly limited, but is preferably 98.0% by mass or more, more preferably more than 99.0% by mass, more preferably 99.90% by mass or more, and 99.95% by mass, relative to the total mass of the chemical solution. An excess is particularly preferred. The upper limit is less than 100% by mass.

Organic solvents may be used individually or in combination of two or more. When using two or more types of organic solvents, it is preferable that the total content is within the above range.

The type of organic solvent is not particularly limited, and known organic solvents can be used. Organic solvents include, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactic acid ester, alkoxypropionic acid, cyclic lactone (preferably having 4 to 10 carbon atoms), and a ring. monoketone compounds (preferably having 4 to 10 carbon atoms), alkylene carbonate, alkyl alkoxyacetate, alkyl pyruvate, dialkyl sulfoxide, cyclic sulfone, dialkyl ether, monohydric alcohol, glycol, alkyl acetate. , and N-alkylpyrrolidone.

Organic solvents include, for example, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone (CHN), ethyl lactate (EL), and propylene carbonate (PC). , isopropanol (IPA), 4-methyl-2-pentanol (MIBC), butyl acetate (nBA), propylene glycol monoethyl ether, propylene glycol monopropyl ether, methyl methoxypropionate, cyclopentane. Onion, γ-butyrolactone, diisoamyl ether, isoamyl acetate, dimethyl sulfoxide, N-methylpyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene glycol At least one selected from the group consisting of chol, ethylene carbonate, sulfolane, cycloheptanone, 2-heptanone, butyl butyrate, isobutyl isobutyrate, isoamyl ether, and undecane is preferred.

Examples of using two or more organic solvents include the combined use of PGMEA and PGME, and the combined use of PGMEA and PC.

Additionally, the type and content of the organic solvent in the chemical solution can be measured using a gas chromatograph mass spectrometer.

<Metal components>

The chemical solution contains a metal component.

The metal component is composed of metal-containing particles and metal ions. For example, when referring to the content of the metal component, it represents the total content of the metal-containing particles and metal ions.

The metal-containing particles just need to contain metal atoms, and examples include metal oxide particles, metal nitride particles, and metal particles. In addition, metal particles mean particles made only of metal.

The metal component contained in the chemical solution contains silver ions.

The content of silver ions is 0.0010 to 1.0 ppt by mass relative to the total mass of the chemical solution, and since metal residue defects are less likely to occur on the silicon substrate, 0.0020 to 0.90 ppt by mass is preferable, and 0.05 to 0.90 ppt by mass is more preferable. It is preferable, and 0.10 to 0.90 mass ppt is more preferable.

The metal component contained in the chemical solution may contain silver oxide particles.

When the chemical solution contains silver oxide particles, the mass ratio of the content of silver oxide particles to the content of silver ions of 1 (content of silver oxide particles/content of silver ions) is not particularly limited and is often 0.000000010 to 1.5. . Among them, the mass ratio 1 is preferably 0.00000010 to 0.1, more preferably 0.000001 to 0.01, and 0.00001 because metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate or silicon oxide film. ~0.005 is more preferred.

Additionally, the content of silver oxide particles is not particularly limited and is often 0.00001 to 10% by mass relative to the content of the silver component in the metal component. Among them, since the effect of the present invention is more excellent, the content of silver oxide particles is preferably 0.00010 to 5.0% by mass, and more preferably 0.010 to 1.0% by mass, relative to the content of the silver component in the metal component.

In addition, the silver component is a component containing a silver atom and is composed of silver-containing particles and silver ions. For example, when referring to the content of the silver component, it represents the total content of the silver-containing particles and silver ions.

Silver-containing particles just need to contain silver atoms, and examples include silver oxide particles, silver nitride particles, and silver particles. In addition, silver particles mean particles made of metallic silver.

The metal component contained in the chemical solution may contain other than the silver component.

The metal component contained in the chemical solution may contain a titanium component. The titanium component is a component containing titanium atoms and is composed of titanium-containing particles and titanium ions. For example, when referring to the content of the titanium component, it represents the total content of titanium-containing particles and titanium ions.

Titanium-containing particles just need to contain titanium atoms, and examples include titanium oxide particles, titanium nitride particles, and titanium particles. Additionally, titanium particles mean particles made of metal titanium.

The metal component contained in the chemical solution may contain titanium oxide particles and titanium ions.

The mass ratio 2 (content of titanium oxide particles/content of titanium ions) of the content of titanium oxide particles to the content of titanium ions is not particularly limited, but it is necessary to satisfy the relationship between the above-mentioned mass ratio 1 and the following equation (A). desirable.

Equation (A) Mass ratio 2>Mass ratio 1

The ratio of the content of titanium oxide particles to the content of silver oxide particles (content of titanium oxide particles/content of silver oxide particles) is not particularly limited and is often 10 ¹ to 10 ¹⁰ . Among them, the ratio is preferably 10 ² to 10 10 , and more preferably 10 ³ to ^{10 10 because} metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate or silicon oxide film. do.

The number of titanium oxide particles is not particularly limited, and in many cases is 10 ⁰ to 10 ¹¹ . Among them, the number of titanium oxide particles is preferably 10 ² to 10 10, and 10 ³ to ^{10 10} because metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate or silicon oxide film. A dog is more preferable.

The content of titanium oxide particles is not particularly limited, and is often 1 to 99% by mass relative to the content of the titanium component in the metal component. Among them, since metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate or silicon oxide film, the content of titanium oxide particles is 5% by mass or more relative to the content of the titanium component in the metal component. Less than 98 mass% is preferable, and 10 to 90 mass% is more preferable.

Among titanium oxide particles, the proportion of particles with a particle size of 0.5 to 17 nm is not particularly limited, and is often 30 to 99% by mass. Among them, since metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate or silicon oxide film, the proportion of particles with a particle size of 0.5 to 17 nm among the titanium oxide particles is 40% by mass or more and 99% by mass. Less than % is preferable, and 70 to 98 mass % is more preferable.

The metal component contained in the chemical solution may contain platinum ions.

The content of platinum ions is not particularly limited, and is often 0.000001 to 1.5 ppt by mass relative to the total mass of the chemical solution. Among them, since metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate, the content of platinum ions is preferably 0.000010 to 1.0 mass ppt, and 0.00010 to 0.50 mass ppt, relative to the total mass of the chemical solution. is more preferable, and 0.001 mass% or more and less than 0.20 mass ppt is more preferable.

The metal component contained in the chemical solution may contain gold ions.

The content of gold ions is not particularly limited, and is often 0.000001 to 1.5 ppt by mass relative to the total mass of the chemical solution. Among them, since metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate, the gold ion content is preferably 0.000010 to 1.0 mass ppt, and 0.00010 to 1.0 mass ppt, relative to the total mass of the chemical solution. is more preferable, and 0.001 mass% or more and less than 0.10 mass ppt are more preferable.

The metal component contained in the chemical solution may contain components of metal atoms other than those described above.

Other metal atoms include, for example, Na (sodium), K (potassium), Ca (calcium), Fe (iron), Cu (copper), Mg (magnesium), Mn (manganese), Li (lithium), and Al. (aluminum), Cr (chromium), Ni (nickel), and Zr (zirconium).

The metal component contained in the chemical solution may contain copper oxide particles and copper ions.

The mass ratio 3 (content of copper oxide particles/content of copper ions) of the content of copper oxide particles to the content of copper ions is not particularly limited, but it is necessary to satisfy the relationship between the above-mentioned mass ratio 1 and the following equation (B). desirable.

Equation (B) Mass ratio 3>Mass ratio 1

The metal component contained in the chemical solution may contain iron oxide particles and iron ions.

The mass ratio 4 (content of iron oxide particles/content of iron ions) of the content of iron oxide particles to the content of iron ions is not particularly limited, but it is necessary to satisfy the relationship between the above-mentioned mass ratio 1 and the following equation (C). desirable.

Equation (C) Mass ratio 4>Mass ratio 1

The metal component may be a metal component unavoidably included in each component (raw material) contained in the chemical solution, or may be a metal component unavoidably included during the manufacture, storage, and/or transport of the chemical solution, or may be added intentionally. You can do it.

The content of the metal component is not particularly limited, but since metal residue defects or composite residue defects described later are less likely to occur on the silicon substrate or silicon oxide film, it is 1 to 500,000 ppt by mass relative to the total mass of the chemical solution. It is preferable, and 5 to 1000 ppt by mass is more preferable.

Additionally, the type and content of metal ions and metal-containing particles in the chemical solution can be measured by SP-ICP-MS (Single Nano Particle Inductively Coupled Plasma Mass Spectrometry).

Here, the SP-ICP-MS method uses the same equipment as the normal ICP-MS method (inductively coupled plasma mass spectrometry), and is different only in data analysis. Data analysis of the SP-ICP-MS method can be performed using commercially available software.

With the ICP-MS method, the content of the metal component to be measured is measured regardless of its existence form. Therefore, the total mass of the metal-containing particles to be measured and the metal ions is quantified as the content of the metal component.

On the other hand, the content of metal-containing particles can be measured using the SP-ICP-MS method. Therefore, the content of metal ions in the sample can be calculated by subtracting the content of metal-containing particles from the content of metal components in the sample.

Examples of the SP-ICP-MS method include Agilent 8800 triple quadrupole ICP-MS (inductively coupled plasma mass spectrometry, for semiconductor analysis, option #200) manufactured by Agilent Technologies, Inc., as described in the examples. It can be measured by method. As other devices than the above, in addition to NexION350S manufactured by PerkinElmer, Agilent 8900 manufactured by Agilent Technologies can also be used.

In addition, since metal-containing particles of 10 nm or less cannot be measured by SP-ICP-MS, the method described in paragraphs 0015 to 0067 of Japanese Patent Application Laid-Open No. 2009-188333 (hereinafter also referred to as “specific method”) is used.

Here, the number of particles of 0.5 to 10 nm remaining on the substrate is counted using a specific method, and the converted value from SNP-ICP-MS of particles of 20 nm is used for the count. Since the conversion value is different for each metal, this conversion is performed for each metal.

The specific method of conversion is as follows.

For example, if the number of 20 nm titanium oxide particles in the chemical solution is 10 by SNP-ICP-MS, and the number of 20 nm titanium oxide particles remaining on the substrate calculated by a specific method is 1, the converted value is 10. In other words, if the number of 1 nm titanium oxide particles that can be confirmed by a specific method is 100, the converted value is calculated as 10 times the base and calculated as 1000 (100 × 10) in the chemical solution. In the present invention, the number of particles of 10 nm or less is estimated for any metal using this conversion method.

<Organic impurities>

The chemical solution may contain organic impurities.

The content of organic impurities in the chemical solution is not particularly limited, but is preferably 1,000 to 100,000 ppt by mass relative to the total mass of the chemical solution because spot-like residual defects, which will be described later, are less likely to occur on the silicon substrate.

In addition, the organic impurity means an organic compound that is different from the organic solvent and is contained in a content of 10000 mass ppm or less with respect to the total mass of the organic solvent. That is, in this specification, organic compounds contained in a content of 10000 mass ppm or less relative to the total mass of the organic solvent correspond to organic impurities and do not correspond to the organic solvent.

Organic impurities are often mixed or added to the chemical solution during the process of purifying the product to be purified to obtain the chemical solution. Examples of such organic impurities include plasticizers, antioxidants, and compounds derived from these (typically decomposition products).

<Water>

The chemical solution may contain water. Water is not included in the above organic impurities.

The water is not particularly limited, and for example, distilled water, ion-exchanged water, and pure water can be used.

Water may be added to the chemical solution or may be unintentionally mixed into the chemical solution during the manufacturing process of the chemical solution. Cases of unintentional mixing during the manufacturing process of the chemical solution include, for example, cases where water is contained in the raw materials (e.g., organic solvents) used in the manufacturing of the chemical solution, and cases where water is mixed during the manufacturing process of the chemical solution ( For example, contamination), etc. may be mentioned, but are not limited to the above.

The water content in the chemical solution is not particularly limited, but is preferably 2.0 mass% or less, and more preferably 500 mass ppb or less, relative to the total mass of the chemical solution. The lower limit is not particularly limited, but may be 0 mass%. The water content in the chemical solution refers to the water content measured using a device based on the Karl Fischer water measurement method.

<Use of chemical solution>

The chemical solution of the present invention is preferably used in the manufacture of semiconductor devices. Among them, it is preferable to manufacture a semiconductor chip using the chemical solution of the present invention.

Specifically, in the manufacturing process of a semiconductor device including a lithography process, an etching process, an ion implantation process, and a peeling process, it is used to treat organic substances after completion of each process or before moving to the next process. Specifically, it is suitably used as a prewet liquid, developer, rinse liquid, and polishing liquid.

In addition, the chemical solution may also be used as a diluent or the like (in other words, a solvent) for the resin contained in the composition for forming a resist film.

In addition, the chemical solution can be used for other purposes other than for manufacturing semiconductor devices, and can also be used as a developer and rinse solution for polyimide, sensor resist, and lens resist.

Additionally, the chemical solution can also be used as a solvent for medical purposes or cleaning purposes. For example, it can be suitably used for cleaning pipes, containers, and substrates (e.g., wafers, glass, etc.).

As for the above-mentioned cleaning use, it is also preferable to use it as a cleaning liquid (piping cleaning liquid, container cleaning liquid, etc.) for cleaning piping and containers, etc. that come into contact with liquids such as the above-mentioned prewet liquid.

Among them, the chemical solution is suitably used as a prewet solution, developer solution, rinse solution, polishing solution, and composition for forming a resist film. Among them, it exhibits more excellent effects when applied to prewet liquid, developer, and rinse liquid. In particular, when applied to prewet solution, developer solution, and rinse solution when the exposure light source is EUV, it exhibits a more excellent effect. Moreover, even when applied to the pipe cleaning liquid used in the pipe used for transporting these liquids, it exhibits a more excellent effect.

<Method for producing chemical solution>

The method for producing the chemical solution is not particularly limited, and known production methods can be used. Among them, in order to obtain a chemical solution that exhibits more excellent effects of the present invention, it is preferable that the method for producing a chemical solution include a filtration step in which a chemical solution is obtained by filtering a purified product containing an organic solvent using a filter.

The purified product used in the filtration process may be procured through purchase, etc., or may be obtained by reacting raw materials. As the product to be purified, it is preferable that the content of impurities is low. Examples of commercially available products of such purified products include commercially available products called “high purity grade products.”

The method of reacting the raw materials to obtain the product to be purified (typically, the product to be purified containing an organic solvent) is not particularly limited, and known methods can be used. For example, there is a method of obtaining an organic solvent by reacting one or more raw materials in the presence of a catalyst.

More specifically, for example, a method of reacting acetic acid and n-butanol in the presence of sulfuric acid to obtain butyl acetate; A method of reacting ethylene, oxygen, and water in the presence of Al(C ₂ H ₅ ) ₃ to obtain 1-hexanol; A method of reacting cis-4-methyl-2-pentene in the presence of Ipc2BH (Diisopinocampheylborane) to obtain 4-methyl-2-pentanol; A method of reacting propylene oxide, methanol, and acetic acid in the presence of sulfuric acid to obtain PGMEA (propylene glycol 1-monomethyl ether 2-acetate); A method of obtaining IPA (isopropyl alcohol) by reacting acetone and hydrogen in the presence of copper oxide-zinc oxide-aluminum oxide; Examples include a method of reacting lactic acid and ethanol to obtain ethyl lactate.

(filtration process)

The method for producing a chemical solution of the present invention preferably includes a filtration step of obtaining a chemical solution by filtering the product to be purified using a filter. There are no particular restrictions on the method of filtering the substance to be purified using a filter, but it is preferable to pass (pass) the substance to be purified under pressure or without pressure through a filter unit having a housing and a filter cartridge stored in the housing.

·Fine pore diameter of the filter

The fine pore diameter of the filter is not particularly limited, and a filter with a fine pore diameter commonly used for filtration of purified substances can be used. Among them, the fine pore diameter of the filter is preferably 200 nm or less, more preferably 20 nm or less, and even more preferably 10 nm or less, because it is easier to control the number of particles (metal particles, etc.) contained in the chemical solution to a desired range. And, 5 nm or less is particularly preferable. The lower limit is not particularly limited, but generally 1 nm or more is preferable from the viewpoint of productivity.

Additionally, in this specification, the fine pore diameter of the filter means the fine pore diameter determined by the bubble point of isopropanol (IPA).

It is preferable that the fine pore diameter of the filter is 5.0 nm or less because it is easier to control the number of particles contained in the chemical solution. Hereinafter, a filter with a fine pore diameter of 5.0 nm or less is also referred to as a “micro pore diameter filter.”

Additionally, the fine pore diameter filter may be used alone or may be used with filters having different fine pore diameters. Among them, from the viewpoint of superior productivity, it is preferable to use a filter having a larger fine pore diameter. That is, when two or more filters are used, it is desirable that at least one filter have a fine pore diameter of 5.0 nm or less. In this case, if the purified material previously filtered through a filter having a larger fine pore diameter is passed through the fine pore diameter filter, clogging of the fine pore diameter filter is prevented.

That is, the fine pore diameter of the filter is preferably 5.0 nm or less when using one filter, and when using two or more filters, the fine pore diameter of the filter with the minimum fine pore diameter is 5.0 nm. nm or less is preferred.

There are no particular restrictions on the form of sequentially using two or more types of filters with different fine pore diameters, but an example is the method of arranging the filter units already described in order along the conduit through which the purified material is transported. At this time, in order to keep the flow rate of the purified material per unit time constant throughout the pipe, a greater pressure may be applied to a filter with a smaller pore diameter compared to a filter with a larger pore diameter. In this case, a pressure adjustment valve, a damper, etc. are placed between the filters to keep the pressure applied to the filter with a small fine pore diameter constant, or filter units containing the same filter are arranged in parallel along the pipe. Therefore, it is desirable to increase the filtration area. In this way, the number of particles in the chemical solution can be controlled more stably.

·Filter material

The material of the filter is not particularly limited, and known materials can be used as the material of the filter. Specifically, in the case of resin, polyamides such as nylon (for example, 6-nylon and 6,6-nylon); polyolefins such as polyethylene and polypropylene; polystyrene; polyimide; polyamideimide; poly(meth)acrylate; Polytetrafluoroethylene, perfluoroalkoxyalkane, perfluoroethylenepropene copolymer, ethylene/tetrafluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer, polychlorotrifluoroethylene, poly fluoride polyfluorocarbons such as vinylidene and polyvinyl fluoride; polyvinyl alcohol; polyester; cellulose; Cellulose acetate, etc. can be mentioned.

Among them, nylon (among them, 6,6-nylon is preferable), polyolefin (among them, polyethylene is preferable), and poly(meth) because it has better solvent resistance and the obtained chemical solution has better defect suppression performance. At least one selected from the group consisting of acrylates and polyfluorocarbons (among them, polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkane (PFA) are preferred) is preferred. These polymers can be used individually or in combination of two or more types.

Moreover, in addition to resin, diatomaceous earth, glass, etc. may be used.

In addition, a polymer (nylon graft UPE, etc.) obtained by graft copolymerizing polyolefin (such as UPE (ultra-high molecular weight polyethylene), which will be described later) with polyamide (for example, nylon such as nylon-6 or nylon-6,6) can be used as a filter. You can use any material.

Additionally, the filter may be a surface-treated filter. The method of surface treatment is not particularly limited, and known methods can be used. Examples of surface treatment methods include chemical modification treatment, plasma treatment, hydrophobic treatment, coating, gas treatment, and sintering.

Plasma treatment is preferable because it makes the surface of the filter hydrophilic. The water contact angle on the surface of the filter made hydrophilic by plasma treatment is not particularly limited, but the static contact angle at 25°C measured with a contact angle meter is preferably 60° or less, and is more preferably 50° or less. It is preferable, and 30° or less is more preferable.

As a chemical modification treatment, a method of introducing an ion exchanger into the filter is preferable.

That is, as a filter, a filter having an ion exchange group is preferable.

Examples of the ion exchange group include cation exchange groups and anion exchange groups. Examples of the cation exchange group include sulfonic acid groups, carboxy groups, and phosphoric acid groups, and examples of the anion exchange groups include quaternary ammonium groups. The method of introducing the ion exchange group into the filter is not particularly limited, and typically includes a method of reacting a compound containing an ion exchange group and a polymerizable group with the filter to form a graft.

The method of introducing the ion exchanger is not particularly limited, but the filter is irradiated with ionizing radiation (α-rays, β-rays, γ-rays, X-rays, and electron beams, etc.) to generate active moieties (radicals). The filter after this irradiation is immersed in a monomer-containing solution, and the monomer is graft-polymerized onto the filter. As a result, the polymer obtained by polymerizing this monomer is grafted onto the filter. The resulting polymer can be contacted and reacted with a compound containing an anion exchange group or a cation exchange group to introduce an ion exchange group into the polymer.

In addition, the filter may be composed of a combination of a woven fabric or non-woven fabric in which an ion exchanger is formed by radiation graft polymerization and a conventional glass wool, woven fabric, or non-woven filter material.

When a filter having an ion exchanger is used, it is easier to control the content of metal-containing particles and metal ions in the chemical solution to a desired range. The material constituting the filter having an ion exchange group is not particularly limited, and includes polyfluorocarbon and a material in which an ion exchange group is introduced into polyolefin, and a material in which an ion exchange group is introduced into polyfluorocarbon is more preferable. .

The fine pore diameter of the filter having an ion exchanger is not particularly limited, but is preferably 1 to 30 nm, and more preferably 5 to 20 nm. The filter having an ion exchanger may also serve as a filter having the minimum fine pore diameter already described, or may be used separately from the filter having the minimum fine pore diameter. Among them, in order to obtain a chemical solution exhibiting better effects of the present invention, it is preferable that the filtration process uses a filter having an ion exchanger and a filter without an ion exchanger and having the minimum fine pore diameter.

The material of the filter having the minimum fine pore diameter already described is not particularly limited, but from the viewpoint of solvent resistance and the like, generally at least one selected from the group consisting of polyfluorocarbon and polyolefin is preferred, and polyolefin is more preferred. desirable.

Therefore, as the filter used in the filtration process, two or more types of filters made of different materials may be used, for example, from the group consisting of polyolefin, polyfluorocarbon, polyamide, and filters made of materials into which an ion exchange group is introduced. You may use two or more of the selected types.

·Fine pore structure of the filter

The fine pore structure of the filter is not particularly limited and may be appropriately selected depending on the components in the product to be purified. In this specification, the fine pore structure of the filter refers to the fine pore diameter distribution, the positional distribution of the fine pores in the filter, and the shape of the fine pores, and is typically controllable by the filter manufacturing method.

For example, when formed by sintering a powder such as resin, a porous membrane is obtained, and when formed by methods such as electrospinning, electroblowing, and meltblowing, a fibrous membrane is obtained. These each have different micropore structures.

“Porous membrane” refers to a membrane that retains components in the purified product such as gels, particles, colloids, cells, and poly oligomers, but allows components substantially smaller than the micropores to pass through the micropores. Retention of components in the product to be purified by the porous membrane may depend on operating conditions, such as face speed, use of surfactant, pH, and combinations thereof, and also on the pore diameter and structure of the porous membrane, and on what must be removed. It may depend on the size and structure of the particles to be processed (hard particles, gels, etc.).

When the product to be purified contains negatively charged particles, a polyamide filter functions as a non-sieve membrane to remove such particles. Typical non-body membranes include, but are not limited to, nylon membranes such as nylon-6 membrane and nylon-6,6 membrane.

In addition, the retention mechanism by "non-sieve" as used herein refers to retention that occurs by mechanisms such as obstruction, diffusion, and adsorption that are not related to the pressure drop of the filter or the fine pore diameter.

Vessel retention includes retention mechanisms such as interference, diffusion, and adsorption that remove particles to be removed in the purified product, regardless of the pressure drop of the filter or the fine pore diameter of the filter. Adsorption of particles to the filter surface may be mediated by, for example, van der Waals forces and electrostatic forces between molecules. An obstruction effect occurs when particles moving within the non-body membrane layer with a meandering path cannot change direction quickly enough to avoid contacting the non-body membrane. Particle transport by diffusion arises primarily from the random or Brownian motion of small particles, creating a constant probability of the particles colliding with the filter medium. If there is no repulsive force between the particles and the filter, the sieve retention mechanism can become active.

UPE filters are typically body membranes. A sieve membrane mainly refers to a membrane that captures particles through a sieve holding mechanism, or a membrane optimized to capture particles through a sieve holding mechanism.

Typical examples of body membranes include, but are not limited to, polytetrafluoroethylene (PTFE) membranes and UPE membranes.

Additionally, the term “sieve holding mechanism” refers to maintaining the result by ensuring that the particles to be removed are larger than the fine pore diameter of the porous membrane. Sieve retention is improved by forming a filter cake (agglomeration of particles to be removed on the surface of the membrane). The filter cake effectively functions as a secondary filter.

The material of the fibrous membrane is not particularly limited as long as it is a polymer capable of forming a fibrous membrane. Examples of polymers include polyamide. Examples of polyamide include nylon 6, nylon 6,6, etc. The polymer forming the fibrous membrane may be poly(ethersulfone). When the fibrous membrane is on the primary side of the porous membrane, the surface energy of the fibrous membrane is preferably higher than that of the polymer that is the material of the porous membrane on the secondary side. As such a combination, for example, the material of the fibrous membrane is nylon and the porous membrane is polyethylene (UPE).

The method for producing the fibrous membrane is not particularly limited, and known methods can be used. Examples of methods for producing a fibrous membrane include electrospinning, electroblowing, and meltblowing.

There are no particular restrictions on the micropore structure of the porous membrane (for example, porous membranes containing UPE, PTFE, etc.), but examples of the micropore shape include race-shaped, string-shaped, and node-shaped. there is.

The size distribution of fine pores in the porous membrane and the distribution of positions within the membrane are not particularly limited. The size distribution may be smaller, and the distribution position within the film may be symmetrical. Additionally, the size distribution may be larger and the distribution position in the film may be asymmetric (the above film is also called an “asymmetric porous film”). In an asymmetric porous membrane, the size of the pores varies within the membrane, and typically the pore diameter increases from the surface of one membrane toward the surface of the other membrane. At this time, the surface on the side with many micropores with large pore diameters is called the “open side,” and the surface on the side with many micropores with small pore diameters is also called the “tight side.”

Also, examples of the asymmetric porous membrane include membranes in which the size of micropores is the minimum at a predetermined position within the thickness of the membrane (this is also called “hourglass shape”).

Using an asymmetric porous membrane, if the primary side is made into a larger hole, in other words, if the primary side is made open, a pre-filtration effect is generated.

The porous membrane may contain thermoplastic polymers such as PESU (polyethersulfone), PFA (perfluoroalkoxyalkane, copolymer of tetrafluoroethylene and perfluoroalkoxyalkane), polyamide, and polyolefin, It may contain tetrafluoroethylene, etc.

Among them, ultra-high molecular weight polyethylene is preferable as a material for the porous membrane. Ultra-high molecular weight polyethylene refers to thermoplastic polyethylene with very long chains, preferably having a molecular weight of 1 million or more, typically 2 to 6 million.

As the filter used in the filtration process, two or more types of filters with different fine pore structures may be used, or a porous membrane and a fibrous membrane filter may be used in combination. Specific examples include a method of using a nylon fiber membrane filter and a UPE porous membrane filter.

Additionally, it is desirable to thoroughly clean the filter before use.

When an uncleaned filter (or a filter that has not been sufficiently cleaned) is used, impurities contained in the filter are likely to be carried into the chemical solution.

As described above, the filtration process according to the embodiment of the present invention is multi-stage filtration in which the purified material is passed through two or more types of filters that differ in at least one type selected from the group consisting of filter material, fine pore diameter, and fine pore structure. It can be fair.

Additionally, the substance to be purified may be passed through the same filter multiple times, or the substance to be purified may be passed through multiple filters of the same type.

In addition, when preparing the chemical solution of the present invention, it is preferable to use a filter (metal component removal filter) that can selectively remove metal components (particularly metal ions), such as "Purasol SN 200nm".

There are no particular restrictions on the material of the liquid contact portion of the purification device used in the filtration process (refers to the purified product and the inner wall surface that may come into contact with the chemical liquid, etc.), including non-metallic materials (fluorine resin, etc.) and electrolytically polished metal materials. It is preferably formed of at least one type selected from the group consisting of (stainless steel, etc.) (hereinafter, these are also collectively referred to as "corrosion-resistant materials"). For example, the fact that the liquid contact part of the production tank is made of a corrosion-resistant material means that the production tank itself is made of a corrosion-resistant material, or the inner wall of the production tank, etc. is covered with a corrosion-resistant material.

The non-metallic material is not particularly limited, and known materials can be used.

Non-metallic materials include, for example, polyethylene resin, polypropylene resin, polyethylene-polypropylene resin, and fluorine-based resin (e.g., tetrafluoroethylene resin, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene - selected from the group consisting of hexafluorinated propylene copolymer resin, tetrafluorinated ethylene-ethylene copolymer resin, trifluorinated ethylene chloride-ethylene copolymer resin, vinylidene fluoride resin, trifluorinated ethylene chlorinated copolymer resin, and vinyl fluorinated resin, etc. At least one type may be mentioned, but it is not limited to this.

The metal material is not particularly limited, and known materials can be used.

Examples of the metal material include metal materials in which the total content of chromium and nickel exceeds 25% by mass based on the total mass of the metal material, and among these, 30% by mass or more is more preferable. The upper limit of the total content of chromium and nickel in the metal material is not particularly limited, but is generally preferably 90% by mass or less.

Examples of metal materials include stainless steel and nickel-chromium alloy.

Stainless steel is not particularly limited, and known stainless steels can be used. Among them, an alloy containing 8 mass% or more of nickel is preferable, and an austenitic stainless steel containing 8 mass% or more of nickel is more preferable. Austenitic stainless steels include, for example, SUS (Steel Use Stainless)304 (Ni content 8% by mass, Cr content 18% by mass), SUS304L (Ni content 9% by mass, Cr content 18% by mass), and SUS316 (Ni content 18% by mass). 10 mass%, Cr content 16 mass%), and SUS316L (Ni content 12 mass%, Cr content 16 mass%).

The nickel-chromium alloy is not particularly limited, and a known nickel-chromium alloy can be used. Among them, a nickel-chromium alloy having a nickel content of 40 to 75 mass% and a chromium content of 1 to 30 mass% is preferable.

Examples of nickel-chromium alloys include Hastelloy (brand name, same hereinafter), Monel (brand name, same hereinafter), and Inconel (brand name, same hereinafter). More specifically, Hastelloy C-276 (Ni content 63 mass%, Cr content 16 mass%), Hastelloy C (Ni content 60 mass%, Cr content 17 mass%), and Hastelloy C-22 (Ni content 61 mass%, Cr content 22 mass%).

Additionally, the nickel-chromium alloy may further contain boron, silicon, tungsten, molybdenum, copper, and cobalt, etc., in addition to the above-mentioned alloys, if necessary.

The method of electrolytic polishing a metal material is not particularly limited, and known methods can be used. For example, the method described in paragraphs [0011] to [0014] of Japanese Patent Application Publication No. 2015-227501 and paragraphs [0036] to [0042] of Japanese Patent Application Publication No. 2008-264929 can be used.

It is presumed that the chromium content in the passivation layer on the surface of the metal material is greater than the chromium content in the mother phase due to electrolytic polishing. Therefore, it is assumed that if a purification device in which the liquid contact portion is formed of a metal material electrolytically polished is used, metal-containing particles are less likely to flow out into the object to be purified.

Additionally, the metal material may be buff polished. The method of buff polishing is not particularly limited, and known methods can be used. The size of the abrasive grains used for finishing buff polishing is not particularly limited, but #400 or less is preferable because irregularities on the surface of the metal material are likely to become smaller. Additionally, buff polishing is preferably performed before electrolytic polishing.

(Other processes)

The method for producing a chemical solution may further include steps other than the filtration step. Examples of processes other than the filtration process include distillation process, reaction process, and static elimination process.

(distillation process)

The distillation process is a process of distilling a purified substance containing an organic solvent to obtain a distilled purified substance. The method for distilling the purified product is not particularly limited, and known methods can be used. Typically, a distillation column is placed on the primary side of the purification device used in the filtration process, and the distilled purified product is introduced into the production tank.

At this time, the liquid contact part of the distillation column is not particularly limited, but is preferably formed of the corrosion-resistant material already described.

(reaction process)

The reaction process is a process of reacting raw materials to produce a product to be purified containing an organic solvent as a reactant. The method for producing the product to be purified is not particularly limited, and known methods can be used. Typically, a reaction tank is placed on the primary side of the production tank (or distillation column) of the purification device used in the filtration process, and the reactant is introduced into the production tank (or distillation column).

At this time, the liquid contact part of the production tank is not particularly limited, but is preferably formed of the corrosion-resistant material already described.

(Static elimination process)

The destaticization process is a process of destaticizing the object to be purified and reducing the charging potential of the object to be purified.

The static electricity removal method is not particularly limited, and a known static electricity removal method can be used. Examples of the static elimination method include bringing the object to be purified into contact with a conductive material.

The contact time for bringing the product to be purified into contact with the conductive material is preferably 0.001 to 60 seconds, more preferably 0.001 to 1 second, and still more preferably 0.01 to 0.1 second. Conductive materials include stainless steel, gold, platinum, diamond, and glassy carbon.

A method of bringing the substance to be purified into contact with a conductive material includes, for example, a method of placing a grounded mesh made of a conductive material inside the pipe and passing the substance to be purified through it.

Purification of the product to be purified, and all accompanying procedures such as opening of the container, cleaning of the container and equipment, storage and analysis of the solution, are preferably performed in a clean room. The clean room is preferably a clean room of class 4 or higher as defined by the international standard ISO14644-1:2015 established by the International Organization for Standardization. Specifically, it is desirable to meet any one of ISO Class 1, ISO Class 2, ISO Class 3, and ISO Class 4, more preferably ISO Class 1 or ISO Class 2, and ISO Class 1. It is more desirable.

The storage temperature of the chemical solution is not particularly limited, but the storage temperature is preferably 4°C or higher because impurities contained in trace amounts in the chemical solution are less likely to be eluted, and as a result, better effects of the present invention are obtained.

<Medicine receptor>

The chemical solution prepared by the above purification method may be placed in a container and stored until use.

Such a container and the chemical solution contained in the container are collectively called a chemical solution receptor. The chemical solution is taken out from the stored chemical solution container and used.

As a container for storing the chemical solution, for use in semiconductor device manufacturing, it is desirable to have a high level of cleanliness within the container and a low elution of impurities.

Concrete containers that can be used include, but are not limited to, the "Clean Bottle" series manufactured by Isello Chemical Co., Ltd. and the "Pure Bottle" manufactured by Kodama Juicy Industries, Ltd.

As a container, for the purpose of preventing contamination (contamination) of impurities into the chemical liquid, a multi-layer bottle with an inner wall of the container made of a 6-layer structure made of 6 types of resin, or a multi-layer bottle made of a 7-layer structure made of 6 types of resin. It is also desirable to use . Examples of these containers include those described in Japanese Patent Application Publication No. 2015-123351.

The liquid-contacting part of this container may be the corrosion-resistant material already described (preferably electropolished stainless steel or fluorine-based resin) or glass. In order to achieve more excellent effects of the present invention, it is preferable that 90% or more of the area of the liquid-contacted portion is made of the above-mentioned material, and it is more preferable that the entire liquid-contacted portion is made of the above-mentioned material.

The porosity within the container of the chemical liquid receptor is preferably 2 to 80 volume%, more preferably 2 to 50 volume%, and still more preferably 5 to 30 volume%.

Additionally, the porosity is calculated according to equation (1).

Equation (1): Porosity = {1-(volume of chemical solution in container/volume of container)}×100

The container volume has the same meaning as the internal volume (capacity) of the container.

By setting the porosity within this range, storage stability can be ensured by limiting contamination such as impurities.

Example

The present invention will be described in more detail below based on examples. Materials, usage amounts, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Accordingly, the scope of the present invention should not be construed as limited by the examples shown below.

In addition, in the preparation of the chemical solutions of Examples and Comparative Examples, handling of containers, preparation of the chemical solutions, filling, storage, and analysis measurements were all performed in a clean room at a level that satisfies ISO Class 2 or 1.

(filter)

As a filter, the following filter was used.

·"Purasol SN 200nm": UPE membrane (material), manufactured by Entegris, pore diameter 200nm

·"PP 200nm": polypropylene filter, manufactured by Entegris, hole diameter 200nm

·"Purasol SP 200nm": UPE membrane (material) manufactured by Entegris, pore diameter 200nm

·"Octolex 5nm": Nylon filter graft made by UPE, manufactured by Entegris, hole diameter 5nm

·"IEX 15nm": Ion exchange resin filter, manufactured by Entegris, pore diameter 15nm

·"IEX 50nm": Ion exchange resin filter, manufactured by Entegris, pore diameter 50nm

·"IEX 200nm": Ion exchange resin filter, manufactured by Entegris, pore diameter 200nm

・"PTFE 5nm": polytetrafluoroethylene filter, manufactured by Entegris, pore diameter 5nm

・"PTFE 7nm": polytetrafluoroethylene filter, manufactured by Entegris, pore diameter 7nm

·"PTFE 10nm": polytetrafluoroethylene filter, manufactured by Entegris, hole diameter 10nm

·"PTFE 20nm": polytetrafluoroethylene filter, manufactured by Entegris, hole diameter 20nm

·"Nylon 5nm": Nylon filter, manufactured by Pall, hole diameter 5nm

·"UPE 1nm": ultra-high molecular weight polyethylene filter, manufactured by Pall, pore diameter 1nm

·"UPE 3nm": ultra-high molecular weight polyethylene filter, manufactured by Pall, pore diameter 3nm

·"UPE 5nm": ultra-high molecular weight polyethylene filter, manufactured by Pall, pore diameter 5nm

<Purified product>

For the preparation of the chemical solutions of Examples and Comparative Examples, the following organic solvents were used as substances to be purified.

·CyHe: Cyclohexanone

·PGMEA: Propylene glycol monomethyl ether acetate

·MIBC: 4-methyl-2-pentanol

・nBA: Butyl acetate

·EL: ethyl lactate

PC: Propylene carbonate

·IPA: Isopropanol

·PGMEE: Propylene glycol monoethyl ether

·PGMPE: Propylene glycol monopropyl ether

·CPN: Cyclopentanone

In addition, “Raw Material 1” to “Raw Material 19” in the table indicate that the organic solvents used in each Example and Comparative Example were purchased from the following manufacturers.

“Raw Material 1”: Honeywell

“Raw Material 2”: Toyokosei

“Raw material 3”: BASF

“Raw Material 4”: Ube Kosan

“Raw Material 5”: KH Neochem

“Raw Material 6”: Showa Denko

“Raw Material 7”: KMG Electronic Chemical

“Raw Material 8”: WAKO

“Raw Material 9”: KH Neochem

"Raw Material 10": Sanwa Yuka High School

“Raw Material 11”: Shell Groval

“Raw Material 12”: Kanto Kagaku

“Raw Material 13”: Junyaku Hayashi

“Raw 14”: CCP

“Raw 15”: BASF

“Raw 16”: ENF

“Raw 17”: Shiny

“Raw Material 18”: KH Neochem

“Raw Material 19”: Junyaku Hayashi

<Courage>

As a container for storing the chemical solution, the following container was used.

·EP-SUS: Container whose wetted part is electropolished stainless steel

<Purification procedure>

One type selected from the above purified substances was selected and subjected to distillation purification treatment as shown in Table 1.

In addition, "U-1" in the "Distillation and Purification" column in the table indicates that atmospheric distillation was performed using a distillation column (theoretical stages: 15 stages), and "U-2" indicates decompression using a distillation tower (theoretical stages: 25 stages). Indicates that distillation was performed. "U-3" indicates that reduced pressure distillation was performed twice using a distillation tower (theoretical stages: 30 stages), and "U-4" indicates normal pressure distillation using a distillation tower (theoretical stages: 20 stages). Indicates that "U-5" indicates that atmospheric distillation was performed using a distillation tower (theoretical stages: 10 stages), and "U-6" indicates that atmospheric distillation was performed using a distillation tower (theoretical stages: 8 stages).

However, “no” in the “distillation purification” column in the table indicates that no distillation treatment was performed, and in the cases where “distillation purification” column is “no”, no distillation purification was performed.

Next, the purified substance purified by distillation was stored in a storage tank, and the purified substance stored in the storage tank was filtered by passing it through filters 1 to 5 shown in Table 1 in this order and stored in the storage tank.

Next, the purified material stored in the storage tank is filtered through filters 6 to 7 shown in Table 1, and the purified material after filtering through filter 7 is circulated upstream of filter 6 and filtered again through filters 6 to 7. Circular filtration. Processing was carried out.

After the circulation filtration treatment, the chemical solution was placed in a container.

Additionally, for Examples 113 to 116, water was added to the chemical solution so that the moisture content reached a predetermined value.

Additionally, during the above-described series of purification processes, the liquid-contact parts of various devices (e.g., distillation towers, pipes, storage tanks, etc.) that come into contact with the purified product were made of electrolytically polished stainless steel.

The contents of the organic component and metal component of the chemical solution were measured by the method shown below.

<Content of metal components>

The content of metal components (metal ions, metal-containing particles) in the chemical solution was measured by a method using ICP-MS and SP-ICP-MS.

The following device was used.

Manufacturer: PerkinElmer

·Format: NexION350S

The following analysis software was used for analysis.

·Syngistix nano application module dedicated to “SP-ICP-MS”

Syngistix for ICP-MS software

However, since metal-containing particles of 10 nm or less cannot be measured by SP-ICP-MS, the specific method described above was used.

<Content of organic impurities>

The content of organic impurities in various chemical solutions was analyzed using a gas chromatography mass spectrometry (GC/MS) device (manufactured by Agilent, GC: 7890B, MS: 5977B EI/CI MSD).

<Test>

[Prewet liquid or rinse liquid]

The method shown below was used to evaluate the defect suppression property of the prepared chemical solution when used as a prewet solution or rinse solution.

First, a chemical solution is spin-discharged onto a silicon substrate with a diameter of 300 mm or a silicon substrate with a silicon oxide film (a silicon substrate whose surface is covered with a silicon oxide film) with a diameter of 300 mm, and each chemical solution is applied to the surface of the substrate while rotating the substrate. 0.5cc was discharged. Afterwards, the substrate was spin dried. Next, using the wafer inspection device "SP-5" manufactured by KLA-Tencor, the number of defects present in the substrate after application of the chemical solution was measured (this is taken as the measured value).

Next, using energy-dispersive X-ray spectroscopy (EDAX), the types of defects were classified into metal residue defects, composite residue defects, and spot-like residue defects. A metal residue defect is a residue derived from a metal component, a composite residue defect is a residue derived from a complex of an organic substance and a metal component, and a spot residue defect is a residue derived from an organic substance.

Additionally, if the “metal residue defect on Si” is “D” or higher, it is suitably used as a prewet liquid or rinse liquid.

<Individual evaluation (metal residue defects, composite residue defects, spot residue defects)>

A: The number of corresponding defects was 20 or less per board.

B: The number of corresponding defects exceeded 20 per board and was less than 50 per board.

C: The number of corresponding defects exceeded 50/substrate and was 100/substrate or less.

D: The number of corresponding defects exceeded 100/substrate and was 150/substrate or less.

E: The number of corresponding defects exceeded 150/board.

〔developer〕

Using the method shown below, the prepared chemical solution was evaluated when it was used as a developing solution.

First, a resist pattern was formed by the operation shown below.

The actinic ray-sensitive or radiation-sensitive resin composition described later is applied to a silicon substrate with a diameter of 300 mm or a silicon substrate with a silicon oxide film with a diameter of 300 mm, and prebaked (PB) is performed at 100 ° C. for 60 seconds to form a film. A resist film with a thickness of 150 nm was formed.

(Active ray-sensitive or radiation-sensitive resin composition)

Acid-decomposable resin (resin expressed by the following formula (weight average molecular weight (Mw): 7500): Numerical values written in each repeating unit mean mol%): 100 parts by mass

[Formula 1]

Photoacid generator shown below: 8 parts by mass

[Formula 2]

Parts shown below: 5 parts by mass (mass ratio, in order from the left, is 0.1:0.3:0.3:0.2). In addition, among the compounds below, the polymer type polymer has a weight average molecular weight (Mw) of 5000. In addition, the numerical value written in each repeating unit means the molar ratio.

[Formula 3]

Hydrophobic resin shown below: 4 parts by mass (mass ratio, in order from the left, is 0.5:0.5). In addition, among the hydrophobic resins below, the hydrophobic resin on the left has a weight average molecular weight (Mw) of 7000, and the hydrophobic resin on the right has a weight average molecular weight (Mw) of 8000. In addition, in each hydrophobic resin, the numerical value written in each repeating unit means the molar ratio.

[Formula 4]

solvent:

PGMEA (propylene glycol monomethyl ether acetate): 3 parts by mass

Cyclohexanone: 600 parts by mass

γ-BL (γ-butyrolactone): 100 parts by mass

The wafer on which the resist film was formed was subjected to pattern exposure at 25 mJ/cm ² using an ArF excimer laser scanner (Numerical Aperture: 0.75). After that, it was heated at 120°C for 60 seconds. Next, it was developed by puddle for 30 seconds with each developer (chemical solution). Next, the wafer was rotated at a rotation speed of 4000 rpm for 30 seconds to form a negative resist pattern. After that, the obtained negative resist pattern was heated at 200°C for 300 seconds. Through the above process, an L/S pattern with a line/space ratio of 1:1 (average pattern width: 45 nm) was obtained.

In the space portion of the obtained sample, the presence or absence of the above-mentioned metal residue defects, composite residue defects, and spot-like residue defects was evaluated according to the above method.

Additionally, in each example, the pressure difference between each filter was 0.01 to 0.03 MPa.

In Table 1, "Use 1" in the "Use" column means that the above test was conducted using the chemical liquid described in each Example and Comparative Example as a prewet liquid and a rinse liquid. “Use 2” in the “Use” column means that the above test was conducted using the chemical solution described in each Example and Comparative Example as a developer.

In addition, in the table, "metal residue on Si" shows the evaluation results of metal residue defects on the silicon substrate, and "composite residue on Si" shows the evaluation results of composite residue defects on the silicon substrate, " In "Spot-like residue on Si", the evaluation results of spot-like residual defects on a silicon substrate are shown, and in "Metal residue on SiO ₂ ", the evaluation results of metal residue defects on a silicon substrate with a silicon oxide film are shown, “Composite residue on SiO ₂ ” shows the evaluation results of composite residue defects on a silicon substrate with a silicon oxide film.

In Table 1, the "Ag ion amount (mass ppt)" column indicates the silver ion content (mass ppt) relative to the total mass of the chemical solution. The “metal component (mass ppt)” column indicates the content (mass ppt) of the metal component relative to the total mass of the chemical solution. The “oxidized Ag particle/Ag ion” column indicates a mass ratio of 1 of the content of silver oxide particles to the content of silver ions. The “Pt ion amount (mass ppt)” column indicates the content of platinum ions (mass ppt) relative to the total mass of the chemical solution. The “Au ion amount (mass ppt)” column indicates the gold ion content (mass ppt) relative to the total mass of the chemical solution. The “Number of Ti oxide particles” column indicates the number of titanium oxide particles in the chemical solution. The “Ti oxide particle/oxidized Ag particle” column represents the ratio of the content of titanium oxide particles to the content of silver oxide particles. The “oxidized Ag particle ratio (mass %)” column indicates the content (mass %) of silver oxide particles relative to the content of the silver component in the metal component. The “Ti oxide particle ratio (mass %)” column indicates the content (mass %) of titanium oxide particles relative to the content of the titanium component in the metal component. The “oxidized Cu particles/Cu ions” column represents the mass ratio of the content of oxidized Cu particles to the content of Cu ions. The “Fe oxide particle/Fe ion” column represents the mass ratio of the content of Fe oxide particles to the content of Fe ions. The column “Ratio (% by mass) of Ti oxide particles of 0.5 to 17 nm” indicates the proportion (% by mass) of particles with a particle size of 0.5 to 17 nm among titanium oxide particles. The “moisture content” column indicates the water content (mass ppb) in the chemical solution relative to the total mass of the chemical solution.

Additionally, in Table 1, “E+number” represents “10 ^numbers ,” and for example, “3.5E+04” represents “3.5×10 ⁴ .”

In Table 1, "<1" represents less than 1.

In Table 1, "<500 ppb" indicates less than 500 ppb by mass.

[Table 1]

[Table 2]

[Table 3]

[Table 4]

[Table 5]

[Table 6]

[Table 7]

[Table 8]

[Table 9]

[Table 10]

[Table 11]

[Table 12]

[Table 13]

[Table 14]

[Table 15]

[Table 16]

[Table 17]

[Table 18]

[Table 19]

[Table 20]

[Table 21]

[Table 22]

[Table 23]

[Table 24]

[Table 25]

[Table 26]

[Table 27]

[Table 28]

[Table 29]

[Table 30]

In Table 1, data related to each Example and Comparative Example are Table 1 [Part 1] <1> to <6>, Table 1 [Part 2] <1> to <6>, Table 1 [Part 3] < 1> to <6>, Table 1 [Part 4] <1> to <6>, and Table 1 [Part 5] <1> to <6>.

For example, in Example 1, as shown in Table 1 [Part 1] <1>, CyHe was used as an organic solvent, and as shown in Table 1 [Part 1] <2>, filter 2 was " IEX 15nm", as shown in Table 1 [Part 1] <3>, the amount of Ag ions in the chemical solution is 0.8 mass ppt, and as shown in Table 1 [Part 1] <4>, the number of Ti oxide particles is 2.1. E+04, as shown in Table 1 [Part 1] <5>, the number of "Fe oxide particles/Fe ions" is 8.7E+4, and as shown in Table 1 [Part 1] <6>, " The rating of “metal residues on Si” is “A”. The same applies to other examples and comparative examples.

From the results shown in the table, it was confirmed that the desired effect was obtained with the chemical solution of the present invention.

In particular, from comparison of Examples 1 to 7 (Examples 29 to 35, Examples 57 to 63, and Examples 85 to 91), when the content of silver ions is 0.0020 to 0.90 ppt by mass based on the total mass of the chemical solution, It was confirmed that it was more effective.

In addition, from the comparison of Examples 8 to 13 (Examples 36 to 41, Examples 64 to 69, and Examples 92 to 97), when the content of the metal component is 10.0 to 500 ppt by mass based on the total mass of the chemical solution, It was confirmed that it was more effective.

Moreover, from the comparison of Examples 14 to 18 (Examples 42 to 46, Examples 70 to 74, and Examples 98 to 102), the mass ratio of the content of silver oxide particles to the content of silver ions is 1, which is 0.00000010 to 0.1. In this case, it was confirmed that the effect was more excellent.

Additionally, from comparison of Examples 4 to 7 (Examples 32 to 35, Examples 60 to 63, and Examples 88 to 91), the content of platinum ions or gold ions was 0.000010 to 1.0 mass ppt based on the total mass of the chemical solution. In this case, it was confirmed that the effect was more excellent.

In addition, from a comparison of Examples 19 to 22 (Examples 47 to 50, Examples 75 to 78, and Examples 103 to 106), it was confirmed that the effect was more excellent when the number of titanium oxide particles was 10 ² to 10 ¹⁰ . It has been done.

Moreover, from the comparison of Examples 23 to 26 (Examples 51 to 54, Examples 79 to 82, and Examples 107 to 110), the ratio of the content of titanium oxide particles to the content of silver oxide particles is 10 ² to 10 ¹⁰ In this case, it was confirmed that the effect was more excellent.

Moreover, from the comparison of Examples 14 to 18 (Examples 42 to 46, Examples 70 to 74, and Examples 98 to 102), the content of silver oxide particles is 0.00010 to 5.0 with respect to the content of the silver component in the metal component. In the case of mass%, it was confirmed that the effect was more excellent.

Additionally, from a comparison of Examples 14 to 18 (Examples 42 to 46, Examples 70 to 74, and Examples 98 to 102), the content of titanium oxide particles is 5% by mass with respect to the content of the titanium component in the metal component. It was confirmed that the effect was more excellent when it was less than 98% by mass.

Additionally, from a comparison of Examples 23 to 26 (Examples 51 to 54, Examples 79 to 82, and Examples 107 to 110), the proportion of particles with a particle size of 0.5 to 17 nm among the titanium oxide particles was 40% by mass or more. It was confirmed that the effect was more excellent when it was less than mass %.

In addition, from Examples 27 and 28 (55 and 56, 83 and 84, 111 and 112), it was confirmed that the effect was more excellent when the content of organic impurities was 1,000 to 100,000 ppt by mass relative to the total mass of the chemical solution.

Moreover, from Examples 1 and 2, it was confirmed that the effect was more excellent when the moisture content was 500 ppb by volume or less.

After cleaning the container (EP-SUS) and various devices used in <Purification Procedure> using the chemical solution (100 L) of Example 29, the chemical solution of Example 29 prepared separately was flowed through the cleaned device and cleaned. It was collected in one container, and solution A was obtained in the container.

In addition, after cleaning the container (EP-SUS) and various devices used in <Purification Procedure> using the chemical solution (100 L) of Example 40, the chemical solution of Example 29, prepared separately, was flowed through the cleaned device. , was collected into a washed container, and solution B was obtained in the container.

"Metal residue defects on Si" were evaluated using solution A and solution B, and solution A gave better results.

<Example (EUV exposure)>

First, resist composition 1 was obtained by mixing each component in the following composition.

·Resin (A-1): 0.77g

·Made generator (B-1): 0.03g

·Basic compound (E-3): 0.03g

·PGMEA (commercial product, high purity grade): 67.5g

·Ethyl lactate (commercially available, high purity grade): 75g

·Resin (A-1)

As the resin (A-1), the following resin was used.

[Formula 5]

·Mine generator (B-1)

As the photoacid generator (B-1), the following compounds were used.

[Formula 6]

·Basic compound (E-3)

As the basic compound (E-3), the following compounds were used.

[Formula 7]

(Formation and evaluation of patterns)

First, resist composition 1 was applied on a silicon wafer with a diameter of 300 mm, and baked (PB: Prebake) at 100°C for 60 seconds to form a resist film with a thickness of 30 nm.

This resist film was exposed through a reflective mask using an EUV exposure machine (manufactured by ASML; NXE3350, NA0.33, Dipole 90°, outer sigma 0.87, inner sigma 0.35). Afterwards, it was heated at 85°C for 60 seconds (PEB: Post Exposure Bake). Next, development was performed by spraying a developing solution (butyl acetate/FETW) for 30 seconds using a spray method, and rinsing was performed by discharging a rinse solution onto the silicon wafer for 20 seconds using a rotary coating method. Subsequently, the silicon wafer was rotated at a rotation speed of 2000 rpm for 40 seconds to form a line-and-space pattern with a space width of 20 nm and a pattern line width of 15 nm.

As the rinse liquid, the chemical liquid used in Example 80 described above was used. In addition, the various evaluations described above were performed, and the desired effects with the same tendency as in Table 1 were obtained.

Claims (7)

A chemical solution containing an organic solvent and a metal component,
The metal component contains silver ions,
The content of the metal component is 10.0 to 500 ppt by mass, based on the total mass of the chemical liquid,
The silver ion content is 0.0020 to 0.90 ppt by mass based on the total mass of the chemical liquid,
wherein the metal component contains silver oxide particles,
The metal component contains titanium oxide particles and titanium ions,
The mass ratio 1 of the content of the silver oxide particles to the content of the silver ions and the mass ratio 2 of the content of the titanium oxide particles to the content of the titanium ions satisfy the relationship of the following formula (A), Method of forming a resist pattern using a chemical solution.
Equation (A) mass ratio 2>mass ratio 1 In claim 1,
A method of forming a resist pattern comprising a resist film forming step of forming a resist film using an actinic ray-sensitive or radiation-sensitive resin composition. In claim 2,
A method of forming a resist pattern, wherein the radiation-sensitive resin composition includes a resin. In claim 3,
A method of forming a resist pattern, wherein the resin contains a repeating unit having a lactone structure. In claim 3,
A method of forming a resist pattern, wherein the resin contains a repeating unit having a hydroxy styrene structure. In claim 2,
The resist film forming process includes an exposure process of exposing the resist film,
A method of forming a resist pattern, wherein the actinic ray or radiation used for the exposure is extreme ultraviolet ray. A method for manufacturing a semiconductor device using the method for forming a resist pattern according to any one of claims 1 to 6.