Substrate cleaning solution, method for manufacturing a cleaned substrate using the same, and method for manufacturing a device

Abstract

To obtain a substrate cleaning liquid capable of cleaning a substrate and removing particles. [Solution] A substrate cleaning liquid is provided, which comprises an insoluble or slightly soluble solute (A), a soluble solute (B), and a solvent (C), wherein the solvent (C) comprises water (C-1); the content of the soluble solute (B) is 0.1 to 500 mass% based on the water (C-1).

Description

[Technical Field]

[0001] The present invention relates to a substrate cleaning liquid for cleaning a substrate and a method for cleaning a substrate using the same.

[0002] Conventionally, substrate manufacturing processes have sometimes generated foreign matter, for example, during lithography processes. Therefore, substrate manufacturing processes sometimes include a cleaning process to remove particles from the substrate. Cleaning processes include a method of physically removing particles by supplying a cleaning liquid such as deionized water (DIW) to the substrate, and a method of chemically removing particles using a chemical solution. However, as patterns become finer and more complex, the patterns become more susceptible to physical or chemical damage.

[0003] As a substrate cleaning process, a method has been considered in which a film is formed on the substrate, particles are retained in the film, and the film is then removed with a remover. If the formed film is completely dissolved with a remover, the particles retained in the film may re-adhere. Therefore, a method has been considered in which the formed film is partially dissolved and the undissolved portions are removed in a solid state (for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-212889 [Patent Document 2] Japanese Patent Application Publication No. 2019-212890 Summary of the Invention [Problem to be solved by the invention]

[0005] The inventors have found that there are one or more problems that require improvement in the technology for forming a film on a substrate and removing particles, such as the following: particle removal is inefficient; the formed film is not completely removed with the remover and remains on the substrate; the film remains even after cleaning after removal with the remover; the solute is not completely dissolved in the solvent or precipitates. The present invention has been made based on the above-mentioned technical background, and provides a substrate cleaning liquid. [Means for solving the problem]

[0006] The substrate cleaning solution according to the present invention comprises an insoluble or slightly soluble solute (A), a soluble solute (B), and a solvent (C), wherein the solvent (C) comprises water (C-1); The content of the soluble solute (B) is 0.1 to 500 mass% based on the water (C-1), Preferably, the substrate cleaning liquid is dropped onto the substrate and dried to remove at least a part of the solvent (C) and form a film, and then the film is removed from the substrate with a removal liquid; Preferably, the insoluble or poorly soluble solute (A) is insoluble or poorly soluble in the removal solution; and / or Preferably, the soluble solute (B) is soluble in the removal liquid.

[0007] A method for producing a cleaned substrate according to the present invention comprises the following steps: (1) Drop the substrate cleaning solution onto the substrate; (2) removing at least a portion of the solvent (C) in the substrate cleaning solution to form a film; (3) retaining particles on a substrate with the film; (4) A remover is supplied onto the substrate to remove the film on which the particles are held.

[0008] A method for manufacturing a device according to the present invention comprises the method for manufacturing the above-described cleaned substrate. [Effects of the Invention]

[0009] By using the substrate cleaning solution according to the present invention, one or more of the following effects can be expected. Efficient particle removal is possible; the formed film can be sufficiently peeled off and removed from the substrate; the film can be sufficiently removed because there is a part in the film that triggers peeling; it is not necessary to dissolve most of the film to remove it, so it is possible to prevent the detachment of retained particles; the film can be efficiently removed by washing after removing the removal solution; the solute dissolves well in the solvent. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view for explaining the state of a substrate surface during cleaning of the substrate according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] The embodiments of the present invention will be described in detail below.

[0012] definition In this specification, unless otherwise specified, the definitions and examples set forth in this paragraph shall be followed. The singular includes the plural, and "one" and "the" mean "at least one." An element of a concept can be expressed by a plurality of species, and when an amount thereof (e.g., mass % or mole %) is stated, the amount refers to the sum of the plurality of species. "And / or" includes all combinations of elements as well as any single element. When a numerical range is indicated using "~" or "-", it includes both endpoints and the units are the same. For example, 5 to 25 mol % means 5 mol % or more and 25 mol % or less. "C x-y Designations such as "," "Cx-Cy" and "Cx" refer to the number of carbons in a molecule or substituent. 1-6Alkyl refers to alkyl chains having from 1 to 6 carbons (methyl, ethyl, propyl, butyl, pentyl, hexyl, etc.). When a polymer has multiple types of repeating units, these repeating units are copolymerized. This copolymerization may be alternating copolymerization, random copolymerization, block copolymerization, graft copolymerization, or a mixture of these. When polymers or resins are represented by structural formulas, the n or m in parentheses indicates the repeating number. The temperature unit is Celsius. For example, 20 degrees means 20 degrees Celsius. The additive refers to the compound itself that has that function (for example, in the case of a base generator, it refers to the compound itself that generates a base). The compound may be dissolved or dispersed in a solvent and added to the composition. In one embodiment of the present invention, such a solvent is preferably contained in the composition of the present invention as the solvent (C) or another component.

[0013] <Substrate cleaning solution> The substrate cleaning solution according to the present invention comprises an insoluble or slightly soluble solute (A) (hereinafter sometimes referred to as component (A), the same applies to (B) and subsequent components), a soluble solute (B), and a solvent (C), where (C) comprises water (C-1); the content of the soluble solute (B) is 0.1 to 50 mass% based on the water (C-1). Preferably, the insoluble or slightly soluble solute (A) is insoluble or slightly soluble in the remover. Preferably, the soluble solute (B) is soluble in the remover. In the present invention, the "solute" is not limited to a state in which it is dissolved in the solvent (C), and a suspended state is also acceptable. In a preferred embodiment of the present invention, the solute, components, and additives contained in the substrate cleaning solution are dissolved in the solvent (C). A substrate cleaning solution in this form is considered to have good filling performance or film uniformity.

[0014] The substrate cleaning liquid according to the present invention is preferably dropped onto a substrate and dried to remove at least a portion of the solvent (C) and form a film, and then the film is removed from the substrate with a removal liquid. "Forming a film" means that a single film is formed and the solutes coexist in one film. One form of film formation is "solidification" of the solute. Note that the film obtained from the substrate cleaning liquid only needs to be solid enough to hold particles, and the solvent (C) is not completely removed (e.g., by evaporation). The substrate cleaning liquid gradually shrinks to form a film as the solvent (C) evaporates. It is acceptable for a very small amount of the insoluble or slightly soluble solute (A) and the soluble solute (B) to be removed (e.g., evaporated or volatilized). For example, it is acceptable for 0 to 10% by mass (preferably 0 to 5% by mass, more preferably 0 to 3% by mass, even more preferably 0 to 1% by mass, and even more preferably 0 to 0.5% by mass) to be removed relative to the original amount. Without intending to limit the scope of the invention and without being bound by theory, it is believed that the film holds particles on the substrate and is removed by the removal solution described below. It is also believed that the soluble solute (B) in the film creates areas that trigger the film to peel off. It is believed that the inclusion of water (C-1) in the film facilitates the peeling of the soluble solute (B) from the substrate, achieving efficient peeling.

[0015] <Insoluble or slightly soluble solute (A)> The substrate cleaning solution according to the present invention comprises an insoluble or slightly soluble solute (A). The insoluble or slightly soluble solute (A) comprises at least one of a novolak derivative, a phenol derivative, a polystyrene derivative, a polyacrylic acid derivative, a polymaleic acid derivative, a polycarbonate derivative, a polyvinyl alcohol derivative, a polymethacrylic acid derivative, and a copolymer of a combination thereof.

[0016] The novolak derivative preferably contains the following repeating unit: [ka] During the ceremony, X is independently C 1ー27 X is preferably methyl or t-butyl; more preferably methyl. a1 is 1 to 2; preferably 1. a2 is 0 to 3; preferably 0 or 1; more preferably 1. More specifically, the repeating unit of the novolak derivative may have the following structure: [ka]

[0017] The phenol derivative is not particularly limited, but is preferably one that has a molecular weight of 150 or more and is solid at room temperature (20°C). More specific embodiments of the phenol derivative include compounds represented by the following formula and polymers thereof. [ka] In the formula, R1 to R5 each independently represent hydrogen, C 1-6 It is alkyl (preferably methyl, ethyl, isopropyl or normal propyl), hydroxy, phenyl, benzyl, aldehyde, amino, nitro, or sulfo. More specifically, the phenol derivative has the following structure: [ka]

[0018] The polystyrene derivative may be a polyhydroxystyrene derivative, and is more preferably a polyhydroxystyrene derivative. Examples of the polystyrene derivative include those having the following structure: [ka] In the formula, R is hydrogen, C 1-6 It is alkyl (preferably methyl, ethyl, isopropyl or normal propyl), phenyl, benzyl, aldehyde, amino, or nitro.

[0019] Examples of polyacrylic acid derivatives include those having the following structure: [ka] In the formula, R is C 1-6 It is alkyl (preferably methyl, ethyl, isopropyl or normal propyl), phenyl, benzyl, aldehyde, amino, or nitro.

[0020] Examples of polymaleic acid derivatives include those having the following structure: [ka] In the formula, R1 and R2 each independently represent C 1-6 It is alkyl (preferably methyl, ethyl, isopropyl or normal propyl), phenyl, benzyl, aldehyde, amino, or nitro.

[0021] Examples of polycarbonate derivatives include the following: [ka]

[0022] Examples of polyvinyl alcohol derivatives include the following: [ka]

[0023] Examples of polymethacrylic acid derivatives include the following, with polymethyl methacrylate being more preferred. [ka] In the formula, R is C 1-6 It is alkyl (preferably methyl, ethyl, isopropyl or normal propyl), phenyl, benzyl, aldehyde, amino, or nitro.

[0024] The insoluble or slightly soluble solute (A) preferably comprises at least one of a novolak derivative, a phenol derivative, a polyhydroxystyrene derivative, a polyacrylic acid derivative, a polycarbonate derivative, a polymethacrylic acid derivative, and a copolymer of a combination thereof; more preferably comprises at least one of a novolak derivative, a phenol derivative, a polyhydroxystyrene derivative, and a copolymer of a combination thereof; even more preferably comprises at least one of a novolak derivative, a phenol derivative, and a polyhydroxystyrene derivative; and even more preferably comprises a novolak derivative.

[0025] The substrate cleaning solution according to the present invention may contain one or a combination of two or more of the above-mentioned preferred examples as the insoluble or slightly soluble solute (A). For example, the insoluble or slightly soluble solute (A) may contain both a novolak derivative and a polyhydroxystyrene derivative. Preferably, the insoluble or slightly soluble solute (A) does not contain fluorine and / or silicon, more preferably does not contain both. Here, the phrase "the insoluble or slightly soluble solute (A) does not contain fluorine and / or silicon" means that, when (A) is not a polymer, the fluorine and silicon content is preferably 5% by mass or less (more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and still more preferably 0.00% by mass) based on (A); and when (A) is a polymer, it means that the number of repeating units containing fluorine or silicon is preferably 5% or less (more preferably 1% or less, even more preferably 0.1% or less, and still more preferably 0.00%) of the total number of repeating units in (A). The copolymer is preferably a random copolymer or a block copolymer.

[0026] The molecular weight of the insoluble or slightly soluble solute (A) (when it is a polymer, the mass average molecular weight Mw) is preferably 150 to 500,000, more preferably 300 to 300,000, even more preferably 500 to 100,000, and even more preferably 1,000 to 50,000. Here, the mass average molecular weight is the mass average molecular weight in terms of polystyrene, and can be measured by gel permeation chromatography using polystyrene as the standard. The same applies hereinafter.

[0027] The insoluble or slightly soluble solute (A) can be obtained by synthesis. Alternatively, it can be purchased. For example, if purchased, the following suppliers can be mentioned. It is also possible for the supplier to synthesize the insoluble or slightly soluble solute (A) so as to achieve the effects of the present invention. Novolac: Showa Kasei, Asahi Organic Materials, Gunei Chemical Industry, Sumitomo Bakelite Polyhydroxystyrene: Nippon Soda, Maruzen Petrochemical, Toho Chemical Industry Polyacrylic acid derivative: Nippon Shokubai Polycarbonate: Sigma-Aldrich Polymethacrylic acid derivatives: Sigma-Aldrich

[0028] The content of the insoluble or slightly soluble solute (A) is 0.1 to 50 mass %, preferably 0.5 to 30 mass %, more preferably 1 to 20 mass %, even more preferably 1 to 10 mass %, and still more preferably 2 to 7 mass %, based on the substrate cleaning liquid.

[0029] Solubility can be evaluated by known methods. For example, 100 ppm of component (A) or (B) is added to 5.0 mass % aqueous ammonia in a flask at 20 to 35°C (more preferably 25±2°C), the flask is capped, and the mixture is shaken in a shaker for 3 hours. The dissolution of component (A) or (B) can be determined by observing whether the component is dissolved. Shaking may be by stirring. Dissolution can also be determined visually. If the component is not dissolved, the solubility is less than 100 ppm, and if the component is dissolved, the solubility is 100 ppm or more. In this specification, a solubility of less than 100 ppm is considered insoluble or slightly soluble, and a solubility of 100 ppm or more is considered soluble. In this specification, soluble includes slightly soluble in a broad sense. In this specification, solubility increases in the order of insoluble, slightly soluble, and soluble. In this specification, slightly soluble is considered less soluble than soluble, and more soluble than slightly soluble. Preferably, the solubility of component (A) in 5.0 mass % ammonia water is less than 100 ppm, and the solubility of component (B) in 5.0 mass % ammonia water is 100 ppm or more. The 5.0 mass% ammonia water may be replaced with the remover (described below) used in a subsequent process. The liquid used in the solubility evaluation and the remover do not need to be the same; the presence of components with different solubilities is considered to be one key to achieving the effects of the present invention. A preferred embodiment of the present invention is one in which component (B) present in the film formed from the substrate cleaning liquid is dissolved by the remover, triggering the film to peel off. Therefore, the effects of the present invention can be expected if a portion of component (B) can be dissolved by the remover. Therefore, for example, the effects of the present invention are considered to be achieved even if the remover is weaker in alkalinity than the liquid used in the solubility evaluation.

[0030] <Soluble solute (B)> The substrate cleaning solution according to the present invention comprises a soluble solute (B). The soluble solute (B) is preferably a substance comprising a carboxyl, sulfo, or phospho group; more preferably a substance comprising a carboxyl or phospho group; and even more preferably a substance comprising a carboxyl group.

[0031] The acid dissociation constant pKA(H2O) of the soluble solute (B) is preferably -5 to 11; more preferably -1 to 8; even more preferably 1 to 7; and even more preferably 2 to 6.

[0032] The soluble solute (B) is preferably (B') a crack promoting component, which preferably comprises a carboxyl-containing hydrocarbon.

[0033] Without intending to limit the scope of the invention and without being bound by theory, it is believed that when the substrate cleaning solution dries to form a film on the substrate, and when the remover solution peels off the film, the soluble solute (B) creates a portion that triggers the film to peel off. For this reason, it is preferable that the soluble solute (B) has a higher solubility in the remover solution than the insoluble or poorly soluble solute (A).

[0034] The soluble solute (B) preferably comprises a constitutional unit represented by formula (B-1). [ka] where: L1 is a single bond, C 1-4 It is a linker selected from at least one of alkylene, phenylene, ether, carbonyl, amide, and imide; preferably a linker selected from at least one of a single bond, methylene, ethylene, phenylene, and amide; more preferably a linker selected from a single bond and phenylene; and even more preferably a single bond. When L1 is a linker selected from amide and imide, H present at a position other than the connection between R1 and the main chain may or may not be substituted with methyl; more preferably, it is not substituted. R1 is carboxyl, sulfo, or phospho; preferably, carboxyl or sulfo; more preferably, carboxyl. R2 is hydrogen, methyl, or carboxyl; preferably hydrogen or carboxyl; more preferably hydrogen. R3 is hydrogen or methyl; preferably hydrogen.

[0035] The soluble solute (B) is preferably a polymer comprising a structural unit represented by formula (B-1). Suitable examples of the polymer comprising a structural unit represented by formula (B-1) include polyacrylic acid, polymaleic acid, polystyrene sulfonic acid, or a polymer of a combination thereof. More suitable examples include polyacrylic acid and a maleic-acrylic acid copolymer. In the case of copolymerization, random copolymerization or block copolymerization is preferred, and random copolymerization is more preferred. As an example, the following maleic acid acrylic acid copolymer will be described: This copolymer is included in (B-1) and has two types of (B-1) structural units. [ka]

[0036] The molecular weight of the soluble solute (B) (when it is a polymer, the mass average molecular weight Mw) is preferably 500 to 500,000; preferably 1,000 to 100,000; more preferably 2,000 to 50,000, even more preferably 5,000 to 50,000; and still more preferably 5,000 to 40,000.

[0037] Soluble solutes (B) can be obtained synthetically or commercially from suppliers such as Sigma-Aldrich, Tokyo Chemical Industry Co., Ltd., and Nippon Shokubai.

[0038] The content of the soluble solute (B) is preferably 1 to 100% by mass, more preferably 1 to 50% by mass, even more preferably 1 to 30% by mass, and still more preferably 1 to 10% by mass, based on the insoluble or slightly soluble solute (A).

[0039] <Solvent (C)> The substrate cleaning solution according to the present invention comprises a solvent (C). The solvent (C) comprises water (C-1). Based on the water (C-1), the content of the soluble solute (B) is 0.1 to 500 mass%, preferably 0.1 to 100 mass%, more preferably 0.5 to 50 mass%, and even more preferably 0.5 to 10 mass%. The water (C-1) is preferably deionized water (DIW). Although some of the water (C-1) contained in the substrate cleaning solution may be removed during film formation, at least some of it remains in the film after it is formed. Without being bound by theory, it is believed that the presence of water (C-1) in the film promotes penetration of the removal solution into the film, enabling more efficient film removal. When component (B) has an acidic group (e.g., carboxyl), component (B) in the film interacts with water (C-1) to form a film, which is thought to serve as a starting point for facilitating penetration of the removal solution into the film. This is thought to reduce the amount of film residue. The content of water (C-1) is preferably 0.01 to 50 mass %, more preferably 0.01 to 20 mass %, and even more preferably 0.05 to 20 mass %, based on the solvent (C).

[0040] The solvent (C) preferably further comprises an organic solvent (C-2). The organic solvent (C-2) is preferably volatile. In the present invention, "volatile" means that the volatility is higher than that of water. For example, the boiling point of the solvent (C-2) at 1 atmosphere is preferably 50 to 250°C, more preferably 50 to 200°C, even more preferably 60 to 170°C, and even more preferably 70 to 150°C.

[0041] Examples of the organic solvent (C-2) include alcohols such as isopropanol (IPA), ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether (PGME) and propylene glycol monoethyl ether (PGEE), propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monoethyl ether acetate, lactic acid esters such as methyl lactate and ethyl lactate (EL), aromatic hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone, 2-heptanone, and cyclohexanone, amides such as N,N-dimethylacetamide and N-methylpyrrolidone, and lactones such as γ-butyrolactone. These organic solvents can be used alone or in combination. In a preferred embodiment, the organic solvent (C-2) is selected from IPA, PGME, PGEE, EL, PGMEA, and any combination thereof. When two organic solvents are used in combination, the volume ratio is preferably 20:80 to 80:20, and more preferably 30:70 to 70:30. The organic solvent (C-2) preferably has a water solubility of 10 g / 100 g HO or more, more preferably 20 g / 100 g HO or more, even more preferably 25 to 1,000 g / 100 g HO, and even more preferably 50 to 200 g / 100 g HO. The water solubility is preferably measured at room temperature and pressure; room temperature is 20 to 30°C, preferably 22 to 28°C; and normal pressure is preferably standard atmospheric pressure or a range of ±15% around standard atmospheric pressure. In one preferred embodiment of the present invention, by using one type of organic solvent (C-2) that has high solubility in water, it is considered possible to dissolve all of the organic solvents (C-2) in water (C-1) even if the other types of organic solvents (C-2) have low solubility in water.

[0042] In one embodiment of the present invention, the solvent (C) is present in an amount of 0.1 to 99.9 mass % based on the substrate cleaning liquid; preferably 50 to 99.9 mass %; more preferably 75 to 99.5 mass %; even more preferably 80 to 99 mass %; and still more preferably 90 to 99 mass %.

[0043] <Other additives (D)> The substrate cleaning solution of the present invention may further contain other additives (D) in addition to the components (A) to (C). Here, the other additives (D) may include surfactants, acids, bases, antibacterial agents, bactericides, preservatives, or antifungal agents, and may include any combination thereof. The other additives (D) preferably include surfactants. In one embodiment of the present invention, the content of the other additives (D) (when there are multiple additives, the sum of the content) is 0 to 100 mass %, preferably 0 to 10 mass %, more preferably 0 to 5 mass %, even more preferably 0 to 3 mass %, and still more preferably 0 to 1 mass %, based on the insoluble or slightly soluble solute (A). In another embodiment of the present invention, the substrate cleaning solution does not contain other additives (D) (0 mass %).

[0044] <Removal liquid> As described above, the substrate cleaning solution of the present invention is dropped onto a substrate and dried to remove at least a portion of the solvent (C) and form a film. The film is then removed from the substrate with a remover. The film can retain particles present on the substrate, and in one preferred embodiment of the present invention, the film is removed with the remover while retaining the particles. The removal liquid may be alkaline, neutral, or acidic, but is preferably neutral. In one embodiment of the present invention, the pH of the removal liquid is 6 to 8, preferably 6.5 to 7.5, more preferably 6.8 to 7.2, and even more preferably 6.9 to 7.1. A specific embodiment of the neutral removal liquid is DIW. In another embodiment of the present invention, the removal solution may be alkaline. The pH of the alkaline removal solution is 7 to 13, preferably 8 to 13, and more preferably 11 to 12.5. The pH is preferably measured after degassing to avoid the influence of dissolved carbon dioxide gas in the air.

[0045] Without intending to limit the present invention and without being bound by theory, one embodiment of a method for producing a cleaned substrate using a substrate cleaning solution according to the present invention will be described using a schematic diagram to facilitate understanding of the present invention. The substrate cleaning solution used in the embodiment shown in FIG. 1 contains an insoluble or slightly soluble solute (A), a soluble solute (B), and a solvent (C). (a) shows a state in which particles 2 are attached to a substrate 1. (b) shows a state in which the substrate cleaning solution according to the present invention is dropped onto this substrate, and a portion of the solvent (C) dries, resulting in a film of components (A) and (B). In (b), the film becomes a particle retention layer 3. Component (B) is present within the particle retention layer 3. (c) shows a state in which component (B) is dissolved into the removal liquid 5 after removal, resulting in traces 6 in the particle retention layer 3. (d) shows a state in which cracks 7 extend from the traces 6. (e) shows a state in which the film is separated by the extension of the cracks 7 and removed from the substrate, still retaining the particles. (f) shows the state of the resulting cleaned substrate.

[0046] <Cleaning the substrate> The substrate cleaning solution of the present invention can be used to clean a substrate. For cleaning the substrate, known methods and apparatuses (for example, those described in JP 2018-110220 A) can be used. The present invention provides, as one aspect, a method for producing a cleaned substrate. The substrate cleaning method will be explained in more detail below. Hereinafter, the numbers in parentheses indicate the order of the steps. For example, when steps (0-1), (0-2), and (1) are described, the order of the steps is as described above. The method for producing a cleaned substrate according to the present invention comprises the following steps. (1) Dropping the substrate cleaning solution of the present invention onto a substrate; (2) removing at least a portion of the solvent (C) in the substrate cleaning solution to form a film; (3) retaining particles on a substrate with the film; (4) A remover is supplied onto the substrate to remove the film on which the particles are held.

[0047] The method (1) is carried out by dropping the substrate cleaning liquid onto the approximate center of a horizontally positioned substrate using a nozzle or the like in an apparatus suitable for substrate cleaning. The dropping may be in the form of a liquid column or a drop. During the dropping, the substrate may be rotated at, for example, 10 to several tens of rpm, thereby preventing the occurrence of drop marks. The amount of the dropped solution is preferably 0.5 to 10 cc. These conditions can be adjusted so that the substrate cleaning solution is applied and spread evenly. The removal of the (C) solvent in (2) above is carried out by drying, preferably by spin drying. Spin drying is preferably carried out at 500 to 3,000 rpm (more preferably 500 to 1,500 rpm, even more preferably 500 to 1,000 rpm) for preferably 0.5 to 90 seconds (more preferably 5 to 80 seconds, even more preferably 15 to 70 seconds, and even more preferably 30 to 60 seconds). This allows the (C) solvent to dry while the substrate cleaning solution is spread over the entire surface of the substrate. Preferably, the substrate is a disk-shaped substrate with a diameter of 200 to 600 mm (more preferably 200 to 400 mm). The above-mentioned (3) "retaining the particles" is achieved by removing the (C) solvent in the above-mentioned (2), so that the insoluble or slightly soluble (A) solute forms a film and retains the particles. In other words, the above-mentioned (2) and (3) steps can be said to occur continuously in a single operation. Here, the above-mentioned (2) removal of the (C) solvent means that a small amount of the (C) solvent remains in the film. In one embodiment of the present invention, at the end of the above-mentioned (2) and (3) steps, 95% or more (preferably 98% or more, more preferably 99% or more) of the (C) solvent is volatilized and does not remain in the film. The temperature inside the apparatus may be increased in the steps (2) and / or (3). The increase in temperature is expected to promote (C) the evaporation of the solvent and (A) the film formation of solid components such as insoluble or slightly soluble solutes. When the temperature is increased, it is preferably 40 to 150°C.

[0048] In the step (4), a remover is supplied onto the substrate to remove the film (particle retention layer) on which particles are retained. The supply can be performed by dripping, spraying, or immersion. The dripping may be performed so as to form a puddle on the substrate, or may be performed continuously. In one embodiment of the present invention, the remover is dripped onto the center of the substrate while the substrate is rotating at 500 to 800 rpm. When the remover removes (e.g., peels) the particle retention layer, the (B) soluble solute remaining in the film is thought to create areas that trigger the film to peel off. Therefore, it is preferable that the (B) soluble solute has a higher solubility in the remover than the (A) insoluble or poorly soluble solute. In a preferred embodiment of the present invention, the particle retention layer is not completely dissolved by the remover, but is removed from the substrate while retaining the particles. It is believed that the particle retention layer is removed in a state of being cut into small pieces by the "parts that trigger peeling."

[0049] The substrate cleaning method according to the present invention also preferably includes at least one other step than those described above. Such a step includes any step known in the art for cleaning substrates. For example, the following steps may be included: (0-1) A process of etching a substrate to form a pattern and then removing the etching mask. The substrate to be cleaned may be a substrate to be processed, and the processing may be performed by lithography techniques. (0-2) A step of cleaning the substrate. To reduce the number of particles on the substrate, the substrate may be cleaned with a known cleaning liquid (such as a rinse liquid). One of the objects of the present invention is to remove the small amount of particles that remain even after cleaning. (0-3) A step of pre-wetting the substrate. In order to improve the applicability of the substrate cleaning solution of the present invention and spread it evenly over the substrate, it is also suitable to prewet the substrate. Preferred liquids used for prewetting (prewet solutions) include IPA, PGME, PGMEA, PGEE, n-butanol (nBA), pure water, and any combination thereof. (0-4) A step of cleaning the substrate. The step (0-3) of cleaning the substrate to replace the pre-wet liquid is also a suitable embodiment. By adding the step (0-2), the step (0-4) can be eliminated, which is also an embodiment of the present invention.

[0050] (3-1) A step of supplying a liquid onto the particle holding layer. To enhance the hydrophilicity or hydrophobicity (preferably hydrophilicity) of the particle retention layer, a step of supplying a liquid other than the removal liquid may be included after step (3). The liquid preferably has a weaker ability to dissolve the solid components constituting the particle retention layer than the removal liquid. Step (3-1) may be omitted. (5) A step of further cleaning the substrate by dropping water or an organic solvent onto the substrate from which the film carrying the particles has been removed, and removing the pure water or organic solvent. In order to remove localized film residues and particle residues, it is also a preferred embodiment to further wash the substrate with water or an organic solvent (preferably an organic solvent). Examples of the organic solvent include IPA, PGME, PGMEA, PGEE, nBA, and combinations of at least two of these. A specific embodiment is washing with IPA in (5). Without intending to limit the present invention and not being bound by theory, it is believed that when removing localized membrane residues with (5), if component (B) has an acidic group (e.g., carboxyl), component (B) in the membrane forms membrane residues while interacting with water (C-1), thereby increasing affinity with organic solvents and making removal of membrane residues more efficient. (6) A step of drying the substrate. The means for drying the substrate include spin drying, supplying (spraying, etc.) a dry gas, reducing pressure, heating, and any combination thereof.

[0051] <Substrate> Substrates to be cleaned in the present invention include semiconductor wafers, glass substrates for liquid crystal displays, glass substrates for organic electroluminescent displays, glass substrates for plasma displays, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, glass substrates for photomasks, and substrates for solar cells. The substrate may be an unprocessed substrate (e.g., a bare wafer) or a processed substrate (e.g., a patterned substrate). The substrate may be composed of multiple layers stacked together. Preferably, the surface of the substrate is a semiconductor. The semiconductor may be composed of an oxide, a nitride, a metal, or a combination of these. Preferably, the surface of the substrate is selected from the group consisting of Si, Ge, SiGe, Si3N4, TaN, SiO2, TiO2, Al2O3, SiON, HfO2, T2O5, HfSiO4, YO3, GaN, TiN, SiCN, NbN, Cu, Ta, W, Hf, Ru, Co, amorphous carbon, and Al.

[0052] <device> The substrate produced by the cleaning method of the present invention can be further processed to produce a device. Examples of such devices include semiconductors, liquid crystal display elements, organic EL display elements, plasma display elements, and solar cell elements. These can be processed using known methods. After the device is formed, the substrate can be cut into chips, connected to lead frames, and packaged with resin, as needed. An example of such a packaged product is a semiconductor.

[0053] The present invention will be described below with reference to various examples. However, the present invention is not limited to these examples.

[0054] <Comparative Preparation Example 1 of Comparative Cleaning Solution 1> Isopropanol (IPA) is used as the solvent (C-2). Novolak (Mw approximately 5,000) was used as the insoluble or slightly soluble solute (A), and polyacrylic acid (Mw approximately 15,000) was used as the soluble solute (B). (A) and (B) were added to solvent (C-2) so that the solid content (sum of (A) and (B)) of the cleaning solution was 5.0 mass%. The mass ratio of (A) to (B) is as shown in Table 1. That is, in comparative cleaning solution 1, the above addition was performed at a ratio of 100 mass% novolak and 5 mass% polyacrylic acid. This was stirred for 1 hour with a stirrer to obtain a solution with a solid content of 5 mass%. This solution was filtered through Optimizer UPE (Japan Entegris Co., Ltd., UPE, pore size 10 nm). This yielded comparative cleaning solution 1. [ka] [Table 1] In the above table, the lower row of the solute indicates the mass ratio of (A) to (B).

[0055] <Comparative Preparation Examples 2 to 8 of Comparative Cleaning Solutions 2 to 8> Comparative cleaning solutions 2 to 8 are prepared in the same manner as in Comparative Preparation Example 1, except that the solute, solvent, and ratio are changed as shown in Table 1, respectively.

[0056] <Evaluation of solubility> Place 4 mg of each component (e.g., novolac (MW approximately 5,000)) in a 50 mL sample bottle and add 5.0% by mass ammonia water to bring the total volume to 40 g. Cover the bottle and shake for 3 hours. This will yield a solution with a component concentration of 100 ppm. The same procedure was carried out as above, except that the amount of each component added was changed to 40 mg, to obtain a 1,000 ppm solution. The solubility of these substances is visually confirmed and the evaluation criteria are as follows: X: Residual dissolution was observed at 100 ppm and 1,000 ppm. It was judged to be insoluble or hardly soluble. Y: No residual substance was found at 100 ppm, but residual substance was found at 1,000 ppm. It is judged to be slightly soluble. Z: No residue was found at 100 ppm and 1,000 ppm. It is judged to be soluble. The evaluation results are shown in Table 1.

[0057] <Preparing the evaluation board for removal evaluation> Particles were attached to a 12-inch bare Si substrate. Ultra-high purity colloidal silica (PL-10H, Fuso Chemical Co., Ltd., average primary particle size 90 nm) was used as the particles for the experiment. 50 mL of the silica microparticle composition was dropped onto the substrate and applied by rotating at 500 rpm for 5 seconds. The solvent in the silica microparticle composition was then spin-dried by rotating at 1,000 rpm for 30 seconds. This yielded an evaluation substrate.

[0058] <Removal evaluation> The evaluation board prepared above is used. Coater Developer RF 3Using a SOKUDO cleaning solution dispenser, 10cc of the cleaning solution was dropped onto the evaluation substrate and rotated at 1,500 rpm for 60 seconds to coat and dry. While rotating the substrate at 100 rpm, 5.0% by mass ammonia water was dropped for 10 seconds, covering the entire substrate with 5.0% by mass ammonia water and maintaining this state for 20 seconds. The substrate was then rotated at 1,500 rpm to peel and remove the film, and the substrate was then dried. The amount of remaining particles on these substrates is compared using a dark field defect inspection system (LS-9110, Hitachi High-Technologies Corporation). The coating condition and film removal condition are checked, the number of remaining particles is counted, and the evaluation is performed according to the following criteria. The evaluation results are shown in Table 1. AA:≦10 pieces A:>10 pieces, ≦100 pieces B:>100 pieces, ≦1,000 pieces C:>1000 pieces D: Film is not evenly applied or removed

[0059] <Evaluation of remaining film amount> 12-inch bare Si substrate, coater / developer RF 3 Using a cleaning solution (SOKUDO Co., Ltd.), 10cc of cleaning solution is dropped onto the substrate, which is then rotated at 1,500 rpm for 60 seconds to allow it to coat and dry. While rotating the substrate at 100 rpm, isopropanol is dropped onto the substrate for 10 seconds, covering the substrate. The rotation of the substrate is stopped, and this state is maintained for 60 seconds. The substrate is then rotated at 1,500 rpm to shake off the cleaning solution and dry the substrate. A film formed by the application and drying of the cleaning solution may not be removed with isopropanol, and the amount of film remaining is evaluated as the amount of remaining film. The remaining film amount on these substrates was measured using an Ellipsometer M-2000 (J.A. Woollam Japan). The evaluation conditions were as follows: AA: No residual film detected. A: A residual film of 0.05 to 0.1 nm is detected. B: A residual film thicker than 0.1 nm is detected. C: Poor coating or inability to remove the film was observed.

[0060] <Preparation Example 1 of Cleaning Solution 1 of the Example> DIW as solvent (C-1) and isopropanol (IPA) as solvent (C-2) are mixed in a volume ratio of 10:90. This mixture is used as solvent (C). Novolak (Mw approximately 5,000) is used as the insoluble or slightly soluble solute (A), and polyacrylic acid (Mw approximately 15,000) is used as the soluble solute (B). (A) and (B) are added to solvent (C) so that the solid content (sum of (A) and (B)) of the cleaning solution is 5.0 mass%. The mass ratio of (A) to (B) is as shown in Table 2-1. This is stirred with a stirrer for 1 hour to obtain a solution with a solid content of 5 mass%. This solution is filtered through Optimizer UPE (Japan Entegris Co., Ltd., UPE, pore size 10 nm). This gives Example Cleaning Solution 1.

[0061] <Preparation Examples 2 to 39 of Cleaning Solutions 2 to 39 of Examples> Example cleaning solutions 2 to 39 are prepared in the same manner as in Preparation Example 1, except that the solute, solvent, and ratio are changed as shown in Tables 2-1 and 2-2, respectively. [Table 2-1] [Table 2-2] In the above table, the lower row for solute means the mass ratio of (A) to (B). In the above table, the lower row for solvent means the volume ratio of (C-1) to (C-2).

[0062] <Evaluation of Example Cleaning Solutions 1 to 39> The solubility, removal evaluation, and residual film amount evaluation were performed using the same procedures as described above. The results are shown in Tables 2-1 and 2-2. It can be confirmed that the cleaning solutions of the examples were favorable in both removal evaluation and residual film amount. Some aspects of the present invention are set out below. [Aspect 1] A substrate cleaning solution comprising an insoluble or poorly soluble solute (A), a soluble solute (B), and a solvent (C): wherein the solvent (C) comprises water (C-1); The content of the soluble solute (B) is 0.1 to 500 mass% based on the water (C-1), Preferably, the substrate cleaning liquid is dropped onto the substrate and dried to remove at least a part of the solvent (C) and form a film, and then the film is removed from the substrate with a removal liquid; Preferably, the insoluble or poorly soluble solute (A) is insoluble or poorly soluble in the removal solution; and / or Preferably, the soluble solute (B) is soluble in the removal liquid. [Aspect 2] The substrate cleaning solution according to embodiment 1, wherein the soluble solute (B) is a substance comprising a carboxyl, sulfo, or phospho group; Preferably, the acid dissociation constant pKA (H 2 O) is -5 to 11. [Aspect 3] The substrate cleaning solution according to embodiment 1 or 2, wherein the solvent (C) further comprises an organic solvent (C-2); Preferably, the organic solvent (C-2) is volatile; and / or Preferably, the organic solvent (C-2) has a boiling point of 50 to 250°C at 1 atmospheric pressure. [Aspect 4] The substrate cleaning solution according to at least any one of Aspects 1 to 3, wherein the insoluble or slightly soluble solute (A) comprises at least one of a novolak derivative, a phenol derivative, a polystyrene derivative, a polyacrylic acid derivative, a polymaleic acid derivative, a polycarbonate derivative, a polyvinyl alcohol derivative, a polymethacrylic acid derivative, and a copolymer of a combination thereof; Preferably, the insoluble or sparingly soluble solute (A) does not contain fluorine and / or silicon. [Aspect 5] 5. The substrate cleaning liquid according to at least one of Aspects 1 to 4, wherein the soluble solute (B) is a crack-accelerating component (B'), and the crack-accelerating component (B') comprises a hydrocarbon containing a carboxyl group. [Aspect 6] The substrate cleaning solution according to at least any one of Aspects 1 to 5, wherein the soluble solute (B) comprises a structural unit represented by formula (B-1):

change

[0063] 1. Substrate 2. Particles 3. Particle retention layer 4. Soluble Solute (B) 5.Removal liquid 6. Traces of soluble solute (B) dissolved 7. Crack

Claims

1. A substrate cleaning solution comprising an insoluble or slightly soluble solute (A), a soluble solute (B), and a solvent (C): wherein the solvent (C) comprises water (C-1) and an organic solvent (C-2); The content of the soluble solute (B) is 0.1 to 50 mass% based on the water (C-1), The content of water (C-1) is 0.01 to 50 mass% based on the solvent (C), The substrate cleaning liquid is dropped onto a substrate and dried to remove at least a part of the solvent (C) and form a film, and then the film is removed from the substrate with a removal liquid; The insoluble or poorly soluble solute (A) is insoluble or poorly soluble in the removal solution; and The soluble solute (B) is soluble in the removal solution.

2. 2. The substrate cleaning solution according to claim 1, wherein the soluble solute (B) is a substance containing carboxyl, sulfo, or phospho.

3. The substrate cleaning solution according to claim 2, wherein the soluble solute (B) has an acid dissociation constant pKA(H 2 O) of −5 to 11.

4. The substrate cleaning solution according to any one of claims 1 to 3, wherein the organic solvent (C-2) is volatile.

5. The substrate cleaning solution according to claim 4, wherein the organic solvent (C-2) has a boiling point of 50 to 250° C. at 1 atmosphere.

6. 6. The substrate cleaning solution according to claim 1, wherein the insoluble or slightly soluble solute (A) comprises at least one of a novolak derivative, a phenol derivative, a polystyrene derivative, a polyacrylic acid derivative, a polymaleic acid derivative, a polycarbonate derivative, a polyvinyl alcohol derivative, a polymethacrylic acid derivative, and a copolymer of a combination thereof.

7. A substrate cleaning solution as described in claim 6, wherein the insoluble or slightly soluble solute (A) does not contain fluorine and / or silicon.

8. 8. The substrate cleaning solution according to claim 1, wherein the soluble solute (B) is a crack-accelerating component (B'), and the crack-accelerating component (B') comprises a hydrocarbon containing a carboxyl group.

9. The substrate cleaning solution according to any one of claims 1 to 8, wherein the soluble solute (B) comprises a structural unit represented by formula (B-1): 【Chemical 1】 where: L １ is a single bond, C １－４ a linker selected from at least one of alkylene, phenylene, ether, carbonyl, amide, and imide; R １ is carboxyl, sulfo, or phospho; R ２ is hydrogen, methyl, or carboxyl; R ３ is hydrogen or methyl.

10. 10. The substrate cleaning solution according to claim 1, wherein the insoluble or slightly soluble solute (A) has a solubility in 5.0 mass % ammonia water of less than 100 ppm, and the soluble solute (B) has a solubility in 5.0 mass % ammonia water of 100 ppm or more; Here, the solubility is determined by determining whether (A) or (B) dissolves when 100 ppm of (A) or (B) is added to 5.0 mass % aqueous ammonia in a flask at 20 to 35°C, the flask is covered with a lid, and the mixture is shaken in a shaker for 3 hours.

11. 11. The substrate cleaning liquid according to claim 1, wherein the content of the insoluble or slightly soluble solute (A) is 0.1 to 50 mass % based on the substrate cleaning liquid.

12. The substrate cleaning solution according to claim 11, wherein the content of the soluble solute (B) is 1 to 100 mass % based on the insoluble or slightly soluble solute (A).

13. The substrate cleaning solution according to claim 11 or 12, wherein the content of the solvent (C) is 0.1 to 99.9 mass % based on the substrate cleaning solution.

14. 14. The substrate cleaning solution according to claim 1, wherein the insoluble or slightly soluble solute (A) has a molecular weight (Mw) of 150 to 500,000.

15. The substrate cleaning solution according to claim 14, wherein the soluble solute (B) has a molecular weight (Mw) of 500 to 500,000.

16. The substrate cleaning solution according to any one of claims 1 to 15, further comprising other additives (D); Here, the other additives (D) include surfactants, acids, bases, antibacterial agents, disinfectants, preservatives, or antifungal agents.

17. A method for producing a cleaned substrate, comprising the steps of: (1) Dropping the substrate cleaning solution according to any one of claims 1 to 16 onto a substrate; (2) removing at least a portion of the solvent (C) in the substrate cleaning solution to form a film; (3) retaining particles on the substrate with the film; (4) A remover is supplied onto the substrate to remove the film on which the particles are held.

18. 18. The method for producing a cleaned substrate according to claim 17, wherein the substrate according to (1) is a non-processed substrate or a processed substrate; the surface of the substrate is a semiconductor, and / or The surface of the substrate is Si, Ge, SiGe, Si ３ N ４ , TaN, SiO ２ , TiO ２ , Al ２ O ３ , SiON, HfO ２ , T ２ O ５ , HfSiO ４ , Y ２ O ３ , GaN, TiN, SiCN, NbN, Cu, Ta, W, Hf, Al, Ru, Co, and amorphous carbon.

19. 19. The method for producing a cleaned substrate according to claim 17 or 18, further comprising at least one of the following steps: (0-1) Etching a substrate to form a pattern, and then removing the etching mask; (0-2) Clean the substrate; (0-3) Pre-wet the substrate; (0-4) Clean the substrate; (5) Water or an organic solvent is dropped onto the substrate from which the film carrying the particles has been removed, and the water or organic solvent is removed, thereby further cleaning the substrate.

20. The method for producing a cleaned substrate according to any one of claims 17 to 19, wherein the step (2) is carried out by spin-drying the substrate; Spin drying is performed at 500 to 3,000 rpm for 0.5 to 90 seconds; and / or The substrate is a disk-shaped substrate having a diameter of 200 to 600 mm.

21. A method for manufacturing a device, comprising the method for manufacturing a cleaned substrate according to any one of claims 17 to 20.

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