Container-loaded chemical liquid for semiconductor production, method for producing container-loaded chemical liquid for semiconductor production, and method for preserving chemical liquid for semiconductor production

Abstract

Provided are: a chemical liquid for semiconductor production, which is held in a container, and in which the container includes, as a base material, an austenitic stainless steel that has been subjected to a passivation treatment, the inner surface of the container is the surface subjected to the passivation treatment, the chemical liquid for semiconductor production contains an organic solvent and at least one metal component selected from the group consisting of V, Sn, and Pb, and the contained amount of the metal component after 30 days have passed since being loaded in the container is 0.1 ppt by mass to 1 ppm by mass; a method for producing a container-loaded chemical liquid for semiconductor production; and a method for preserving a chemical liquid for semiconductor production.

Description

Containerized semiconductor manufacturing chemicals, manufacturing method for containerized semiconductor manufacturing chemicals, and method for storing semiconductor manufacturing chemicals

[0001] The present invention relates to a containerized liquid chemical for semiconductor manufacturing, a method for manufacturing a containerized liquid chemical for semiconductor manufacturing, and a method for storing a liquid chemical for semiconductor manufacturing.

[0002] A semiconductor device is formed by laminating a low-dielectric layer, an insulating layer, metal wiring (layer), etc. on a substrate such as a silicon wafer, and such a semiconductor device is manufactured by forming the above-mentioned layers and metal wiring by a lithography method in which etching is performed using a resist pattern as a mask.

[0003] In the manufacturing process of semiconductor devices, including the above-mentioned lithography step, various chemical liquids for semiconductor manufacturing are used, such as resist liquid, developer liquid, stripping liquid, cleaning liquid, pre-rinse liquid, rinse liquid, chemical mechanical polishing (CMP) slurry, etc.

[0004] With regard to such technology, for example, Patent Document 1 discloses a chemical solution container having a container and a chemical solution contained in the container, wherein the chemical solution contains a solvent, metal-containing particles containing metal atoms, and an organic compound having a ClogP value higher than that of the solvent, the content of the metal-containing particles being 10 ppt by mass or less relative to the total mass of the chemical solution, a gas containing an organic compound having a ClogP value higher than that of the solvent is present in a void portion of the container, and the total content of the organic compound in the gas and the organic compound in the chemical solution is 100,000 ppt by mass or less relative to the total mass of the chemical solution.

[0005] International Publication No. 2020 / 040034

[0006] However, the inclusion of fine particles in semiconductor manufacturing chemicals can cause defects in semiconductor devices. However, after extensive research, the inventors have discovered that simply reducing the particle content in semiconductor manufacturing chemicals is not enough to simultaneously suppress the increase in particles in the chemicals over time due to the passage of storage days and the occurrence of defects.

[0007] The present invention has been made in view of the above-described circumstances, and aims to provide a containerized semiconductor manufacturing chemical liquid that can suppress the increase in particles in the chemical liquid over time and also suppress the occurrence of defects, a method for manufacturing a containerized semiconductor manufacturing chemical liquid, and a method for storing a semiconductor manufacturing chemical liquid.

[0008] As a result of intensive research into achieving the above-mentioned object, the inventors have discovered the following, and have completed the present invention: a chemical liquid for semiconductor manufacturing that is contained in a container, wherein the container includes a passivated austenitic stainless steel as a base material, the passivated surface being the inner surface of the container, the chemical liquid for semiconductor manufacturing containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and wherein the content of the metal components in the chemical liquid for semiconductor manufacturing 30 days after filling the container is 0.1 ppt by mass to 1 ppm by mass.

[0009] That is, the present invention is as follows: <1> A containerized liquid chemical for semiconductor manufacturing housed in a container, the container containing a passivated austenitic stainless steel as a base material, the passivated surface being the inner surface of the container, the liquid chemical for semiconductor manufacturing containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and the content of the metal components in the liquid chemical for semiconductor manufacturing 30 days after filling the container is 0.1 ppt by mass to 1 ppm by mass. <2> The containerized semiconductor manufacturing chemical liquid according to <1>, wherein the semiconductor manufacturing chemical liquid contains two or more metal components selected from the group consisting of V, Sn, and Pb, and wherein the content of each of the two or more metal components in the semiconductor manufacturing chemical liquid 30 days after filling into the container is 1 ppm by mass or less, and the content of at least one of the two or more metal components in the semiconductor manufacturing chemical liquid 30 days after filling into the container is 1 ppt by mass or more. <3> The containerized semiconductor manufacturing chemical liquid according to <1> or <2>, wherein the ratio of the concentration of the metal component in the container 30 days after filling into the container to the concentration of the metal component in the container at the time of filling into the container (after 30 days after filling / at time of filling) is 1 or more and 1.5 or less. <4> The containerized liquid chemical for semiconductor manufacturing according to any one of <1> to <3>, wherein the semiconductor manufacturing liquid chemical contains, as the organic solvent, one or more organic solvents selected from the group consisting of alkylene glycol monoalkyl ether, alkylene glycol monoalkyl ether acetate, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, ethyl lactate, butyl acetate, and 3-methoxybutyl acetate. <5> The containerized liquid chemical for semiconductor manufacturing according to any one of <1> to <4>, wherein the semiconductor manufacturing liquid chemical contains two or more organic solvents. <6> The containerized liquid chemical for semiconductor manufacturing according to any one of <1> to <5>, wherein the passivation treatment is a GEP treatment or a GEPW treatment. <7> The containerized liquid chemical for semiconductor manufacturing according to any one of <1> to <6>, wherein the semiconductor manufacturing liquid chemical is a developer for semiconductor manufacturing or a rinse for semiconductor manufacturing.<8> A method for producing a containerized chemical solution for semiconductor manufacturing, in which the chemical solution for semiconductor manufacturing is contained in a container, the method comprising: a step of preparing, as the container, a container that includes passivated austenitic stainless steel as a base material and has a passivated surface as an inner surface; and a step of filling the container with the chemical solution for semiconductor manufacturing, wherein the chemical solution for semiconductor manufacturing contains one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and 30 days after filling the container, the content of the metal components in the chemical solution for semiconductor manufacturing is 0.1 ppt by mass to 1 ppm by mass. <9> A method for storing a chemical solution for semiconductor manufacturing, the method comprising: preparing a container that contains passivated austenitic stainless steel as a base material and has a passivated surface as an inner surface; and filling the container with a chemical solution for semiconductor manufacturing, the chemical solution for semiconductor manufacturing containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and wherein 30 days after filling the container, the content of the metal components in the chemical solution for semiconductor manufacturing is 0.1 ppt by mass to 1 ppm by mass.

[0010] According to the present invention, it is possible to provide a containerized semiconductor manufacturing chemical liquid, a method for manufacturing a containerized semiconductor manufacturing chemical liquid, and a method for storing a semiconductor manufacturing chemical liquid, which can suppress the increase in particles in the chemical liquid over time and also suppress the occurrence of defects.

[0011] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The following present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be implemented by appropriately modifying it within the scope of its gist. Furthermore, unless otherwise specified, the configurations and parameters disclosed in this specification can be arbitrarily combined. Furthermore, unless otherwise specified, the upper and lower limits of the values ​​disclosed in this specification can be arbitrarily combined.

[0012] <Chemicals for semiconductor manufacturing>

[0013] The semiconductor manufacturing chemical according to this embodiment (hereinafter sometimes simply referred to as "chemical") is a containerized semiconductor manufacturing chemical housed in a container, the container including a base material made of passivated austenitic stainless steel, the passivated surface being the inner surface of the container, the semiconductor manufacturing chemical containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and the content of the metal components in the semiconductor manufacturing chemical 30 days after filling the container is 0.1 ppt by mass to 1 ppm by mass. By using such a chemical, it is possible to suppress the increase in particles in the chemical over time and also the occurrence of defects.

[0014] In the past, studies were based on the simple idea that fine particles that could become particles should be removed, based on the knowledge that in order to suppress the occurrence of defects in chemicals used in semiconductor manufacturing, it is better to have fewer particles in the chemicals. However, the present inventors did not stop at such a simple idea and focused on the fact that there are cases in which defects cannot be sufficiently suppressed by simply reducing the concentration of fine particles.

[0015] As a result of intensive research, the present inventors have unexpectedly found that controlling the content of specific metal components (metal components) such as V, Sn, and Pb in semiconductor manufacturing chemical solutions used for applications such as resist solutions, developing solutions, stripping solutions, cleaning solutions, pre-rinse solutions, rinse solutions, chemical mechanical polishing (CMP) slurries, etc. is effective in suppressing defects in semiconductor devices, etc. Furthermore, the present inventors have also found that one of the reasons why defects cannot be sufficiently suppressed is that, while the above chemical solutions containing specific amounts of metal components such as V, Sn, and Pb are stored in conventional, commonly used SUS containers, etc., the content of various metals increases over time as the storage period progresses until the time of use.

[0016] The chemical solution according to this embodiment has been made based on the above-mentioned findings and is a containerized chemical solution for semiconductor manufacturing housed in a container, the container including a base material made of passivated austenitic stainless steel, the passivated surface being the inner surface of the container, the chemical solution for semiconductor manufacturing containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and the content of metal components in the chemical solution for semiconductor manufacturing 30 days after filling the container is 0.1 ppt by mass to 1 ppm by mass. By providing the containerized chemical solution for semiconductor manufacturing, it is unexpectedly possible to suppress the increase in particles in the chemical solution over time and the occurrence of defects, and to suppress the occurrence of defects that occur during use of the chemical solution to an extent that has not been possible in the past (however, the actions and effects of this embodiment are not limited to those described above).

[0017] (container)

[0018] The container includes a base material made of a passivated austenitic stainless steel, and the passivated surface is the inner surface of the container. Examples of the austenitic stainless steel include, but are not limited to, SUS (Steel Use Stainless Steel) 304 (Ni content: 8% by mass, Cr content: 18% by mass), SUS304L (Ni content: 9% by mass, Cr content: 18% by mass), SUS316 (Ni content: 10% by mass, Cr content: 16% by mass), and SUS316L (Ni content: 12% by mass, Cr content: 16% by mass).

[0019] The container of this embodiment forms and / or grows a passive layer (sometimes called a passive film or passivation film) by passivation treatment, thereby preventing the elution of metal components into the chemical solution for a long period of time. Note that the passive layer referred to here does not include oxide films, etc., that are inevitably formed by oxidation reactions with oxygen in the air, but is an example of a passive layer, etc., that is intentionally formed by passivation treatment. From this perspective, it is preferable that the passive layer be formed uniformly on the surface.

[0020] The passivation treatment method is not particularly limited, but is preferably a thermal oxidation treatment and / or an electropolishing (EP) treatment, more preferably both a thermal oxidation treatment and an electropolishing treatment, and even more preferably an electropolishing treatment followed by a thermal oxidation treatment. By adopting these treatment methods, the passivation layer can be formed more uniformly on the inner surface of the container, and pinholes in the barrier of the passivation layer can be more effectively suppressed.

[0021] Furthermore, the passivation treatment is preferably a GEP (Gold Electro Polishing) treatment or a GEPW (Gold Electro Polishing White) treatment.

[0022] In the case of GEP treatment, a thermal oxidation treatment is performed after an electrolytic polishing treatment (EP treatment). This allows the growth of an iron oxide layer on the surface and a chromium oxide layer underneath. As a result, the unintended elution of particles such as metal components into the chemical solution contained in the container can be more effectively suppressed.

[0023] In the case of GEPW treatment, electrolytic polishing (EP treatment) is followed by thermal oxidation treatment, which removes the surface iron oxide layer and leaves the grown chromium oxide layer, thereby more effectively suppressing the unintended elution of particles such as metal components into the chemical solution contained in the container.

[0024] In this way, the GEP and GEPW processes can be performed as additional processes to electropolishing (EP), allowing a passivation layer to grow on the stainless steel base material. Furthermore, the GEP and GEPW processes can be used selectively depending on the composition of the chemical solution. For example, the GEP process is suitable when the chemical solution contains a large amount of alcohols, etc., while the GEPW process is suitable when the chemical solution contains a large amount of amines, etc. Furthermore, the GEP and GEPW processes can be used selectively depending on the level of dissolved oxygen content in the chemical solution (however, the functions and effects of this embodiment are not limited to these).

[0025] (Ingredients of the drug solution)

[0026] The chemical solution for semiconductor manufacturing contains one or more metal components selected from the group consisting of V, Sn, and Pb. V, Sn, and Pb may be present in the chemical solution as particles of simple metals, or may be dissolved in the chemical solution as metal ions.

[0027] The content of metal components in the semiconductor manufacturing chemicals 30 days after filling the container (sometimes abbreviated as "post-existing content") is 0.1 mass ppt to 1 mass ppm (1,000,000 mass ppt). The lower limit of the metal component content is preferably 0.5 mass ppt or more, more preferably 2 mass ppt or more, even more preferably 5 mass ppt or more, and even more preferably 50 mass ppt or more. The upper limit of the metal component content is preferably 500,000 mass ppt or less, more preferably 50,000 mass ppt or less, even more preferably 5,000 mass ppt or less, even more preferably 650 mass ppt or less, and even more preferably 500 mass ppt or less. By having the post-existing metal component content within the above numerical range, the occurrence of defects can be more effectively suppressed. In addition, when two or more of V, Sn, and Pb are contained as metal components, it is more preferable that the total content of the metal components is within the above range.

[0028] Furthermore, the content of metal components in the semiconductor manufacturing chemical immediately after filling the container (sometimes abbreviated as "post-filling content") is preferably 0.1 mass ppt to 1 mass ppm (1,000,000 mass ppt). The lower limit of the metal component content is preferably 0.5 mass ppt or more, more preferably 5 mass ppt or more, and even more preferably 50 mass ppt or more. The upper limit of the metal component content is more preferably 500,000 mass ppt or less, even more preferably 50,000 mass ppt or less, even more preferably 5,000 mass ppt or less, even more preferably 600 mass ppt or less, and even more preferably 500 mass ppt or less. By having the post-filling content of the metal component be within the above numerical range, the post-filling content of the metal component can be controlled with greater precision so as to be within the above numerical range, and the occurrence of defects can be more effectively suppressed. In addition, when two or more of V, Sn, and Pb are contained as metal components, it is more preferable that the total content of the metal components is within the above range.

[0029] When the semiconductor manufacturing liquid chemical contains two or more metal components selected from the group consisting of V, Sn, and Pb, it is preferable that the content of each of the two or more metal components in the semiconductor manufacturing liquid chemical 30 days after filling the container is 1 ppm by mass or less, and that the content of at least one of the two or more metal components in the semiconductor manufacturing liquid chemical 30 days after filling the container is 1 ppt by mass or more. Note that the upper limit of the content of each of the two or more metal components in the semiconductor manufacturing liquid chemical 30 days after filling the container is more preferably 900,000 ppt by mass or less, even more preferably 100,000 ppt by mass or less, even more preferably 500 ppt by mass or less, and even more preferably 450 ppt by mass or less. The lower limit of this content is preferably greater than 0 ppt by mass, more preferably 0.01 ppt by mass or more, and even more preferably 0.1 ppt by mass or more. Furthermore, the upper limit of the content of at least one of the two or more metal components in the semiconductor manufacturing chemical 30 days after filling the container is preferably 900,000 mass ppt or less, more preferably 100,000 mass ppt or less, even more preferably 500 mass ppt or less, and even more preferably 450 mass ppt or less. The lower limit of this content is preferably greater than 0 mass ppt, more preferably 0.01 mass ppt or more, even more preferably 0.1 mass ppt or more, and even more preferably 1 mass ppt or more.

[0030] According to this embodiment, as described above, the increase in particles in the chemical solution over time can be suppressed, and therefore the increase in the concentration of the metal components in the container can be suppressed over a long period of time. A preferred example of such a configuration is one in which the ratio of the concentration of the metal components in the container 30 days after filling to the concentration of the metal components in the container at the time of filling (after 30 days after filling / at the time of filling) is 1 or more and 1.5 or less. The lower limit of this ratio of the concentrations in the container is preferably 1.00 or more, and more preferably 1.05 or more. Furthermore, the upper limit of this ratio is not particularly limited, but is preferably 10 or less, more preferably 5 or less, even more preferably 3 or less, even more preferably 2.5 or less, and even more preferably 1.5 or less. By having the ratio within the above numerical range, it is possible to achieve both the suppression of the increase in particles in the chemical solution over time due to the passage of storage days and the suppression of the occurrence of defects at an even higher level.

[0031] The chemical liquid for semiconductor manufacturing contains an organic solvent. The organic solvent is not particularly limited, but is preferably at least one selected from the group consisting of alcohol-based solvents, glycol ether-based solvents, glycol ester-based solvents, ketone-based solvents, lactone-based solvents, ester-based solvents, sulfonic acid-based solvents, amide-based solvents, and pyrrolidone-based solvents.

[0032] Specific examples of alcohol-based solvents include aliphatic alcohols such as methanol, ethanol, denatured ethanol, isopropanol, n-propanol, n-butanol, and 3-methoxy-3-methyl-1-butanol; and glycols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, furfuryl alcohol, and hexylene glycol.

[0033] Specific examples of glycol ether solvents include alkylene glycol monoalkyl ethers, alkylene glycol dialkyl ethers, and polymer-type polyalkylene glycol ether solvents.

[0034] Examples of alkylene glycol monoalkyl ethers include ethylene-based glycol monoalkyl ethers such as ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, ethylene glycol monohexyl ether, and diethylene glycol monohexyl ether; and propylene-based glycol monoalkyl ethers such as propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether (DPM), dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, and tripropylene glycol monobutyl ether.

[0035] Examples of alkylene glycol dialkyl ethers include ethylene-based glycol dialkyl ethers such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dibutyl ether, triethylene glycol dibutyl ether, ethylene glycol dihexyl ether, and diethylene glycol dihexyl ether; and propylene-based glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol dipropyl ether, dipropylene glycol dibutyl ether, tripropylene glycol dimethyl ether, tripropylene glycol diethyl ether, and tripropylene glycol dibutyl ether.

[0036] Examples of polyalkylene glycol ethers include polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene butyl ether, polyoxyethylene oleyl ether, and polyoxyethylene polyoxypropylene-2-ethylhexyl ether.

[0037] Among these, ethylene-based glycol monoalkyl ethers, propylene-based glycol monoalkyl ethers, ethylene-based glycol dialkyl ethers, propylene-based glycol dialkyl ethers, etc. are preferred, and propylene glycol monomethyl ether (PGME) and the like are more preferred.

[0038] Specific examples of glycol ester solvents include alkylene glycol monoalkyl ether acetates.

[0039] Examples of the alkylene glycol monoalkyl ether acetate include ethylene-based glycol ether acetates such as ethylene glycol monobutyl ether acetate and diethylene glycol monobutyl ether acetate; and propylene-based glycol ether acetates such as propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol monomethyl ether acetate and propylene glycol diacetate.

[0040] Among these, ethylene glycol ether acetates and propylene glycol ether acetates are preferred, with propylene glycol monomethyl ether acetate (PGMEA) being more preferred.

[0041] Specific examples of ketone solvents include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone, cyclohexanone, cyclopentanone, diacetone alcohol, 1-hexanone, 2-hexanone, 4-heptanone, 2-heptanone, 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetylacetone, acetonylacetone, phenylacetone, acetophenone, methyl naphthyl ketone, methylcyclohexanone, ionone, isophorone, propylene carbonate (propylene carbonate), diacetonyl alcohol, and acetylcarbinol.

[0042] Among these, cyclohexanone, cyclopentanone, 2-heptanone, etc. are preferred.

[0043] Specific examples of lactone solvents include γ-butyrolactone, α-methyl-γ-butyrolactone, β-propiolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, γ-laurolactone, and hexanolactone.

[0044] Among these, γ-butyrolactone and the like are preferred.

[0045] Specific examples of ester solvents include methyl acetate, ethyl acetate, butyl acetate, amyl acetate, propyl acetate, isopropyl acetate, methyl lactate, ethyl lactate, butyl lactate, ethyl methoxyacetate, ethyl ethoxyacetate, 2-methoxybutyl acetate (2-methoxybutyl acetate), 3-methoxybutyl acetate (3-methoxybutyl acetate), 4-methoxybutyl acetate (4-methoxybutyl acetate), 3-methoxy-3-methylbutyl acetate (3-methoxy-3-methylbutyl acetate), 3-ethyl-3-methoxybutyl acetate (3-ethyl-3-methoxybutyl acetate), and 4-methyl-4-methoxypentyl acetate. methyl formate, ethyl formate, propyl formate, butyl formate, ethyl lactate, propyl lactate, butyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, and propyl-3-methoxypropionate.

[0046] Of these, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 3-methoxybutyl acetate, etc. are preferred.

[0047] Specific examples of sulfonic acid solvents include dimethyl sulfone, diethyl sulfone, tetramethylene sulfone, dipropyl sulfone, sulfolane (also known as tetramethylene sulfone), 3-methyl sulfolane, 2,4-dimethyl sulfolane, 3,4-dimethyl sulfolane, diphenyl sulfolane, 3,4-diphenylmethyl sulfolane, sulfolene, 3-methyl sulfolene, and 3-ethyl sulfolene.

[0048] Specific examples of amide solvents include N,N-dimethylformamide (DMF), diethylformamide (DEF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidine (MPD), and hexamethylphosphoric triamide (HMPA).

[0049] Specific examples of pyrrolidone solvents include N-methylpyrrolidone (NMP), 2-pyrrolidone, and N-vinyl-2-pyrrolidone.

[0050] Among the above, it is preferable to contain one or more solvents selected from the group consisting of alcohol-based solvents, glycol ether-based solvents, glycol ester-based solvents, ketone-based solvents, lactone-based solvents, and ester-based solvents; and it is more preferable to contain one or more solvents selected from the group consisting of alkylene glycol monoalkyl ethers, alkylene glycol monoalkyl ether acetates, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, ethyl lactate, butyl acetate, and 3-methoxybutyl acetate.

[0051] The semiconductor manufacturing chemical liquid may contain one organic solvent or two or more organic solvents, but preferably contains two or more organic solvents. When two or more organic solvents are contained, two or more of the above-mentioned organic solvents can be selected as suitable examples. Furthermore, when two or more organic solvents are contained, a preferred combination is preferably two or more selected from the group consisting of alcohol-based solvents, glycol ether-based solvents, glycol ester-based solvents, ketone-based solvents, lactone-based solvents, ester-based solvents, sulfonic acid-based solvents, amide-based solvents, and pyrrolidone-based solvents. As suitable examples thereof, the preferred examples described above can be selected.

[0052] An example of a suitable combination of two or more organic solvents is, for example, preferably containing (i) at least one of glycol ether-based solvents or glycol ester-based solvents, and (ii) one or more selected from the group consisting of alcohol-based solvents, glycol ether-based solvents, glycol ester-based solvents, ketone-based solvents, lactone-based solvents, and ester-based solvents; more preferably containing at least (i) a glycol ether-based solvent and (ii) a glycol ester-based solvent.

[0053] The preferred content ratio of the above-mentioned (i) and (ii) is, in volume ratio, (i):(ii)=1:9 to 9:1, more preferably 3:7 to 9:1, and even more preferably 5:5 to 9:1. For example, in the case of a mixed solvent containing two organic solvents, where (i) is propylene glycol monomethyl ether (PGME) and (ii) is propylene glycol monomethyl ether acetate (PGMEA), the content ratio of PGME to PGMEA (PGME:PGMEA) is, in volume ratio, preferably 1:9 to 9:1, more preferably 3:7 to 9:1, and even more preferably 5:5 to 9:1.

[0054] Alternatively, in another embodiment, it is preferable that the composition contains two or more selected from the group consisting of alkylene glycol monoalkyl ether, alkylene glycol monoalkyl ether acetate, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, ethyl lactate, butyl acetate, and 3-methoxybutyl acetate, and it is more preferable that the composition contains (a) at least one of alkylene glycol monoalkyl ether or alkylene glycol monoalkyl ether acetate, and (b) one or more selected from the group consisting of alkylene glycol monoalkyl ether, alkylene glycol monoalkyl ether acetate, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, ethyl lactate, butyl acetate, and 3-methoxybutyl acetate.

[0055] The preferred content ratio of the above-mentioned (a) and (b) is, in volume ratio, (a):(b)=1:9 to 9:1, more preferably 3:7 to 9:1, and even more preferably 5:5 to 9:1. For example, in the case of a mixed solvent containing two organic solvents, where (a) is propylene glycol monomethyl ether (PGME) and (b) is alkylene glycol monoalkyl ether propylene glycol monomethyl ether acetate (PGMEA), the content ratio of PGME to PGMEA (PGME:PGMEA) is, in volume ratio, preferably 1:9 to 9:1, more preferably 3:7 to 9:1, and even more preferably 5:5 to 9:1.

[0056] By using the above-mentioned combination of organic solvents, it is possible to suppress the increase in particles in the chemical solution over time and to suppress the occurrence of defects at an even higher level.

[0057] The content of the organic solvent is preferably 90 to 100% by mass relative to the total amount of the chemical solution. The lower limit is more preferably 95% by mass or more, and even more preferably 99% by mass or more. The upper limit is preferably less than 100% by mass.

[0058] The chemical solution according to this embodiment may contain water. 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. For example, when a water-soluble organic solvent is contained as the organic solvent, its use in combination with water is expected to sufficiently suppress the increase in particles and the occurrence of defects over time in the chemical solution. The water content may be contained as the balance of components other than water. The water content may be, for example, 0.001% to 2.0% by mass relative to the total amount of the chemical solution. The lower limit may be 0.005% by mass or more, or 0.01% by mass or more. The upper limit may be 1.5% by mass or less, or 1.0% by mass or less. The water content in the chemical solution can be measured by Karl Fischer measurement.

[0059] The chemical solution according to this embodiment may further contain other components depending on the application, as long as the effects of this embodiment can be obtained. Examples of such components include antioxidants (e.g., dibutylhydroxytoluene, etc.), acid generators, basic compounds, acid diffusion controllers, stabilizers, hydrophobic resins, surfactants, etc. Known components may be used as appropriate depending on the application.

[0060] The chemical solution according to this embodiment can be used for various chemical solutions used in the manufacturing process of semiconductor devices, including, for example, resist solutions, developers, strippers, cleaning solutions, pre-rinse solutions, rinse solutions, and chemical mechanical polishing (CMP) slurries. In particular, it is more suitable for use as a developer solution or rinse solution for semiconductor manufacturing (including the pre-rinse solution described above). Because these applications do not require the addition of fine components other than the metal components V, Sn, and Pb, the present embodiment can effectively utilize its advantages of suppressing the increase in particles in the chemical solution over time and suppressing the occurrence of defects. Additionally, the suppression of changes over time also has the advantage of extending the product life.

[0061] The chemical solution according to this embodiment can be used as a container for the chemical solution for semiconductor manufacturing stored in the container described above. That is, the container for the chemical solution for semiconductor manufacturing can be a container for the chemical solution for semiconductor manufacturing that includes the chemical solution for semiconductor manufacturing according to this embodiment and a container for storing the chemical solution for semiconductor manufacturing.

[0062] <Method of manufacturing containerized chemicals for semiconductor manufacturing>

[0063] A preferred embodiment of the method for producing a containerized semiconductor manufacturing chemical liquid of this embodiment is a method for producing a containerized semiconductor manufacturing chemical liquid in which the semiconductor manufacturing chemical liquid is contained in a container, the method including the steps of preparing a container containing a passivated austenitic stainless steel as a base material and having a passivated surface as an inner surface, and filling the container with the semiconductor manufacturing chemical liquid, the semiconductor manufacturing chemical liquid containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and the content of the metal components in the semiconductor manufacturing chemical liquid 30 days after filling the container is 0.1 ppt by mass to 1 ppm by mass. The components to be blended into the semiconductor manufacturing chemical liquid can be selected from those described above as appropriate. The numerical values ​​of the contents and other parameters of the semiconductor manufacturing chemical liquid can also be selected from the above-described conditions as appropriate. The method for mixing the components is not particularly limited, and known methods can be used as appropriate. If necessary, purification treatments such as distillation, filtration using a filter, degassing, etc. may be carried out.

[0064] <Storage method for semiconductor manufacturing chemicals>

[0065] As described above, this embodiment has at least the advantage of being able to suppress an increase in particles in the chemical solution over time, so that a sufficient defect suppression effect can be exerted so that defects do not occur when the chemical solution is used for film formation, etc. From this perspective, this embodiment is suitable as a method for storing chemical solutions for semiconductor manufacturing.

[0066] A preferred embodiment of the method for storing semiconductor manufacturing chemicals according to this embodiment includes the steps of preparing a container containing passivated austenitic stainless steel as a base material and having a passivated surface as an inner surface, and filling the container with the semiconductor manufacturing chemicals, the semiconductor manufacturing chemicals containing one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and the content of the metal components in the semiconductor manufacturing chemicals is 0.1 ppt by mass to 1 ppm by mass 30 days after filling the container. During storage, if necessary, known treatments may be performed, such as filling the container with an inert gas such as nitrogen gas. The components of the semiconductor manufacturing chemicals may be as described above. The numerical values ​​of the contents and other parameters of the semiconductor manufacturing chemicals may also be determined as appropriate using the conditions described above.

[0067] As described above, according to the present embodiment, by controlling the contents of trace amounts of metal components such as V, Sn, and Pb that cause defects, it is possible to suppress the increase in particles in the chemical solution over time and also suppress the occurrence of defects, thereby realizing a containerized semiconductor manufacturing chemical solution, a method for manufacturing a containerized semiconductor manufacturing chemical solution, and a method for storing a semiconductor manufacturing chemical solution.

[0068] The present invention will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples. Unless otherwise specified, the quantities are based on mass, and the experiments were carried out at 25°C and atmospheric pressure.

[0069] In preparing the chemical solutions, unless otherwise specified, handling of the containers, preparation of the chemical solutions, placing them in the containers, storage, and analytical measurements were all carried out in a clean room. Sampling of samples from the containers was carried out in an ISO Class 1000 clean room, and other operations were carried out in an ISO Class 5 clean room. In order to improve measurement accuracy, when measuring the content of metal components below the detection limit in normal measurements, the chemical solutions were concentrated before measurement, and the content was calculated by converting it into the concentration of the solution before concentration.

[0070] <Organic solvent>

[0071] The organic solvents used in the chemical solutions were those listed in Table 1. The abbreviations are as follows: PGMEA: propylene glycol monomethyl ether acetate PGME: propylene glycol monomethyl ether PGME / PGMEA (7:3): a mixed solution of PGME and PGMEA in a volume ratio of 7:3

[0072] <Refining>

[0073] The organic solvents were purified by a distillation process described below followed by a filtration process using the filters shown in Table 1. The number of times the solution was passed through the filter in the filtration process was changed as appropriate. In the case of a mixed solution (PGME / PGMEA (7:3, volume ratio)), the organic solvents (each solution) before mixing were distilled separately, and then mixed in a predetermined ratio to form a mixed solution, which was then filtered using a filter.

[0074] (Distillation process)

[0075] Commercially available organic solvents were subjected to distillation treatment including dehydration at least once to prepare organic solvents with reduced impurities. The water content in each of the organic solvents after distillation was 100 ppm or less.

[0076] (Filtration process)

[0077] After the distillation step, filtration was carried out using the following filters. Before use in filtration, 8 L of each organic solvent was passed through the filter under a pressurized condition of 0.1 MPa to prewet the filter. The filters used in each example and comparative example are shown in Table 1. In comparative example 2, the first stage of filtration was carried out using filter 1, and then the second stage of filtration was carried out using filter 2. Filter 1: "Microgard™ UPE" (filter name), manufactured by Entegris, 1 nm (pore size) Filter 2: "Purasol™ SP" (filter name), manufactured by Entegris, 200 nm (pore size) Filter 3: "Microgard UPE" (filter name), manufactured by Entegris, 10 nm (pore size)

[0078]

[0079] <Containers> Containers used for storing chemical solutions had liquid-contacting parts made of the following materials: - "GEP": Passivated austenitic stainless steel (passivation was achieved by electrolytic polishing (EP) followed by thermal oxidation (GEP) treatment. In other words, this is a container that includes, as its base material, austenitic stainless steel that has been subjected to thermal oxidation treatment as passivation, with the passivated surface (thermally oxidized surface) forming the inner surface of the container. - "SUS": Unpassivated austenitic stainless steel (no passivation treatment, no thermal oxidation treatment, electrolytic polishing). In other words, this is a container that includes, as its base material, austenitic stainless steel that has not been subjected to passivation treatment, with this surface forming the inner surface of the container.

[0080] <Measurement Conditions> (Content of Metal Component) The content of metal components in the chemical solution immediately after the chemical solution was placed in the container (meaning immediately after the chemical solution was placed in the container and sealed), and after 30 days (storage for 30 days after filling) was measured using plasma mass spectrometry (ICP-MS, apparatus name "Agilent 8900 ICP-QQQ", manufactured by Agilent).

[0081] (Evaluation of the rate of increase of particles in liquid)

[0082] The measurement values ​​of particles in the liquid of the examples and comparative examples (LPC values) were measured using a liquid particle counter ("KS-19F", manufactured by RION) at 25°C, measuring the number of particles with a diameter of 30 nm or more (number per mL (particles / mL)). The LPC value (X) immediately after the liquid was placed in the container and the LPC value (Y) after a predetermined number of days had elapsed were measured, and the rate of increase (rate of increase in liquid-borne particles) of the LPC value (Y / X) after a predetermined number of days had elapsed relative to the LPC value immediately after filling with the liquid was calculated. Note that when the shape of the particles is not circular, for example, when they have an irregular shape, the above diameter was taken as the maximum major axis of the irregular shape.

[0083] The increase rate of particles in the liquid was evaluated based on the following criteria: A: The increase rate of the number of particles was 500% or less; B: The increase rate of the number of particles was more than 500% and less than 1000%; C: The increase rate of the number of particles was 1000% or more.

[0084] (Evaluation of defect suppression)

[0085] A dark-field defect inspection system ("Surfscan™ SP5," manufactured by KLA-Tencor) was used to inspect the defects of 12-inch (300 mm diameter) silicon wafers. First, the number of defects (defect count) with a diameter of 17 nm or larger present on the surface of the silicon wafer was measured using the dark-field defect inspection system (this was designated the "initial value"). Next, the substrate was set in a spin-discharge system, and while rotating the substrate at a rotation speed of 1000 rpm, 5 mL of the chemical solution contained in the container was discharged onto the surface of the substrate at a flow rate of 1 mL / s. After discharge, the substrate was spin-dried. Next, using the dark-field defect inspection system, the number of defects with a diameter of 17 nm or larger present on the substrate after application of the chemical solution was counted (this was designated the "measured value"). Note that if the shape of the defects was not circular, for example, if they were irregular, the diameter was designated the maximum long diameter of the irregular shape.

[0086] The difference between the "initial value" and the "measured value" (measured value - initial value) was calculated to determine the number of defects. The defect suppression ability was evaluated based on the following evaluation criteria. The measurement area was the total surface area of ​​the 12-inch (300 mm diameter) silicon wafer used for the inspection, approximately 70650 mm2. ２ The number of defects observed in an area (= 150 mm x 150 mm x 3.14) was counted. A: The number of defects in the measurement area was 100 or less. B: The number of defects in the measurement area was 101 or more and 500 or less. C: The number of defects in the measurement area was 501 or more and 1000 or less. D: The number of defects in the measurement area was 1001 or more.

[0087] The conditions and evaluation results for each example and comparative example are shown in Table 2. Note that 1 ppm by mass = 1,000,000 ppt by mass.

[0088]

[0089] From the above, it was at least confirmed that the chemical solution of this example has a low rate of increase in particles in the solution and is also excellent in defect suppression.

[0090] This application is based on a Japanese patent application (Patent Application No. 2023-221881) filed with the Japan Patent Office on December 27, 2023, the contents of which are incorporated herein by reference.

Claims

1. A chemical solution for semiconductor manufacturing contained in a container, wherein the container contains, as a base material, a passivated austenitic stainless steel, the passivated surface is the inner surface of the container, the chemical solution for semiconductor manufacturing contains one or more metal components selected from the group consisting of V, Sn, and Pb, and an organic solvent, and the content of the metal component in the chemical solution for semiconductor manufacturing 30 days after filling the container is 0.1 mass ppt to 1 mass ppm. A chemical solution for semiconductor manufacturing contained in a container.

2. The chemical solution for semiconductor manufacturing according to claim 1, wherein the chemical solution for semiconductor manufacturing contains two or more metal components selected from the group consisting of V, Sn, and Pb, and the content of each of the two or more metal components in the chemical solution for semiconductor manufacturing 30 days after filling the container is 1 mass ppm or less, and the content of at least one of the two or more metal components in the chemical solution for semiconductor manufacturing 30 days after filling the container is 1 mass ppt or more.

3. The chemical solution for semiconductor manufacturing contained in a container according to claim 1 or 2, wherein the ratio (30 days after filling / at filling) of the concentration of the metal component in the container 30 days after filling the container to the concentration of the metal component in the container at the time of filling the container is 1 or more and 1.5 or less.

4. The chemical solution for semiconductor manufacturing contained in a container according to any one of claims 1 to 3, wherein the chemical solution for semiconductor manufacturing contains one or more selected from the group consisting of alkylene glycol monoalkyl ether, alkylene glycol monoalkyl ether acetate, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolactone, ethyl lactate, butyl acetate, and 3-methoxybutyl acetate as the organic solvent.

5. The chemical solution for semiconductor manufacturing contained in a container according to any one of claims 1 to 4, wherein the chemical solution for semiconductor manufacturing contains two or more of the organic solvents.

6. The chemical solution for semiconductor manufacturing contained in a container according to any one of claims 1 to 5, wherein the passivation treatment is a GEP treatment or a GEPW treatment.

7. The chemical solution for semiconductor manufacturing contained in a container according to any one of claims 1 to 6, wherein the chemical solution for semiconductor manufacturing is a developer for semiconductor manufacturing or a rinse solution for semiconductor manufacturing.

8. A method for manufacturing a chemical solution for semiconductor manufacturing contained in a container, comprising: preparing a container containing an anodized austenitic stainless steel as a base material and having an anodized surface as an inner surface; and filling the container with the chemical solution for semiconductor manufacturing, wherein the chemical solution for semiconductor manufacturing contains at least one metal component selected from the group consisting of V, Sn, and Pb and an organic solvent, and the content of the metal component in the chemical solution for semiconductor manufacturing 30 days after filling the container is 0.1 mass ppt to 1 mass ppm. A method for manufacturing a chemical solution for semiconductor manufacturing contained in a container.

9. A method for storing a chemical solution for semiconductor manufacturing, comprising: preparing a container containing an anodized austenitic stainless steel as a base material and having an anodized surface as an inner surface; and filling the container with the chemical solution for semiconductor manufacturing, wherein the chemical solution for semiconductor manufacturing contains at least one metal component selected from the group consisting of V, Sn, and Pb and an organic solvent, and the content of the metal component in the chemical solution for semiconductor manufacturing 30 days after filling the container is 0.1 mass ppt to 1 mass ppm.

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