Circuit board processing method

Abstract

In one embodiment, a substrate processing method with excellent resin mask removal (peelability) is provided, which includes a step of calculating a new index for preparing a reuse processing liquid. [Solution] This disclosure relates in one embodiment to a method for processing a substrate, comprising the following steps 1, 2, and 3. Step 1: A process of treating a substrate having a resin mask using a treatment solution obtained using an aqueous solution (Solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine. Step 2: A step to determine the concentration of carbonate ions (carbonate concentration) in the processing solution (Solution C) used in Step 1. Step 3: A step to calculate the amount of alkanolamine contained in Solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in Solution C, based on the carbon dioxide concentration in Solution C determined in Step 2.

Description

[Technical Field]

[0001] This disclosure relates to a method for processing substrates. [Background technology]

[0002] In recent years, personal computers and various electronic devices have seen advancements in power consumption, processing speed, and miniaturization, leading to increasingly finer wiring on package substrates and other components. While metal mask methods have traditionally been used for forming such fine wiring and connection terminals like pillars and bumps, their limited versatility and increasing difficulty in adapting to the miniaturization of wiring have led to a shift towards other, newer methods.

[0003] One new method involves using a dry film resist as a thick-film resin mask instead of a metal mask. This resin mask is eventually peeled off and removed, using an alkaline release agent composition (peel-off cleaning agent).

[0004] Alkaline stripping agent compositions typically use mixed solutions of alkalis and organic solvents. Such stripping agent compositions have been reported to degrade due to factors such as the dissolution of resists and reactions with carbon dioxide in the air, leading to a decrease in stripping performance (resin mask removal ability). Therefore, various methods are being investigated to suppress the degradation of stripping agent compositions and extend their lifespan. For example, Patent Document 1 identifies carbon dioxide absorbed into the resist stripping solution as the main factor reducing the resist stripping performance, and proposes a method for managing the resist stripping solution to maintain the carbon dioxide concentration in the resist stripping solution at 3% by weight or less. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2003-122029 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] When forming fine wiring on printed circuit boards and the like, high stripping performance (resin mask removal ability, cleaning ability) is required for the stripping agent composition (processing solution) in order to reduce not only the residue of the resin mask but also the residue of auxiliary agents contained in the solder and plating solution used for forming the fine wiring and bumps. Furthermore, when the release agent composition is reused, the alkaline components and carbon dioxide concentration in the release agent composition change, so it is necessary to replenish or replace the release agent composition according to the concentration analysis results. The amount and mixing ratio of the replenished components must be managed in a way that maintains the composition of the release agent composition appropriately and does not reduce the resin mask removal performance (release ability). For example, when an aliphatic quaternary ammonium hydroxide such as TMAH is used as one of the components of the treatment solution, the aliphatic quaternary ammonium hydroxide is consumed to neutralize the carbonate ions dissolved in the stripping agent composition. In addition, the supply liquid for aliphatic quaternary ammonium hydroxide may sometimes contain some of the other stripping agent components, such as alkanolamines. When preparing a reused treatment solution by adding the above-mentioned supply raw material solution to a post-use treatment solution containing carbon dioxide, it is considered necessary to use a new indicator in the preparation process to suppress the deterioration of the functionality of the reused treatment solution.

[0007] Therefore, this disclosure provides a substrate processing method and a resin mask peeling method that have excellent resin mask removal (peeling) properties, including a step of calculating a new index for preparing a reuse processing liquid. [Means for solving the problem]

[0008] This disclosure relates, in one embodiment, to a method for processing a substrate, including steps 1, 2, and 3 described below. Step 1: A process of treating a substrate having a resin mask using a treatment solution obtained using an aqueous solution (Solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine. Step 2: A step to determine the concentration of carbonate ions (carbonate concentration) in the processing solution (Solution C) used in Step 1. Step 3: A step to calculate the amount of alkanolamine contained in Solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in Solution C, based on the carbon dioxide concentration in Solution C determined in Step 2.

[0009] This disclosure relates, in one embodiment, to a method for processing a substrate, including steps 1, 2, and 3 described below. Step 1: A process of processing a substrate having a resin mask using a processing solution obtained by mixing an aqueous solution containing an aliphatic quaternary ammonium hydroxide and an alkanolamine (Solution A) with an aqueous solution containing an organic solvent and an alkanolamine (Solution B). Step 2: A step to determine the concentration of carbonate ions (carbonate concentration) in the processing solution (Solution C) used in Step 1. Step 3: A step to calculate the amount of alkanolamine contained in Solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in Solution C, based on the carbon dioxide concentration in Solution C determined in Step 2.

[0010] This disclosure relates, in one embodiment, to a method for peeling off a resin mask, which includes peeling off a resin mask from a substrate having a resin mask using the substrate processing method of this disclosure. [Effects of the Invention]

[0011] According to this disclosure, a substrate processing method with excellent resin mask removal (peelability) can be provided, which includes a step of calculating a new index for preparing a reuse processing solution. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic diagram showing an example of the appearance of the substrate surface of a substrate to be cleaned. [Modes for carrying out the invention]

[0013] When the release agent composition is recycled, as described above, since the alkaline components in the release agent composition and the carbonic acid concentration present in the release agent composition change, it is necessary to replenish or replace the release agent composition according to the concentration analysis results. The carbonic acid in the release agent composition can be neutralized using an aliphatic quaternary ammonium hydroxide which is a strong alkali. Therefore, when replenishing an aqueous solution of an aliphatic quaternary ammonium hydroxide to a release agent composition containing carbonic acid, the amount of the aqueous solution of the aliphatic quaternary ammonium hydroxide to be replenished includes not only the amount necessary for the resin mask peeling treatment but also the amount necessary for neutralizing the carbonic acid. The aqueous solution of the aliphatic quaternary ammonium hydroxide to be replenished may contain an alkanolamine. As a result of intensive studies by the present inventors, it has been found that if replenishment is not carried out in consideration of the amount of the alkanolamine contained in the aqueous solution of the aliphatic quaternary ammonium hydroxide to be replenished, the composition of the release agent composition cannot be appropriately maintained and the resin mask removability (peelability) may decrease. Therefore, in one or more embodiments, the present disclosure is based on the finding that when replenishing an aqueous solution (solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine to an alkaline release agent composition (post-treatment liquid) (solution C) containing carbonate ions, the amount of the aliphatic quaternary ammonium hydroxide consumed for neutralizing the carbonic acid is calculated from the carbonic acid concentration in the post-treatment liquid after use in substrate treatment, and the resin mask peelability (removability) can be improved by preparing a recycled treatment liquid in consideration of a new index of the amount of the alkanolamine contained in solution A corresponding to the amount of the aliphatic quaternary ammonium hydroxide.

[0014] That is, in one aspect, the present disclosure relates to a method for treating a substrate (hereinafter, also referred to as "the method for treating a substrate of the present disclosure") including the following steps 1, 2, and 3. Step 1: A step of treating a substrate having a resin mask using a treatment liquid obtained using an aqueous solution (solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine Step 2: A step of determining the concentration of carbonate ions (carbonic acid concentration) in the treatment liquid (solution C) after use in Step 1 Step 3: Calculating the amount of alkanolamine contained in Solution A containing the same amount of aliphatic quaternary ammonium hydroxide as that consumed for neutralizing the carbonic acid in Solution C from the carbonic acid concentration in the treatment liquid (Solution C) determined in Step 2 In other aspects, the present disclosure relates to a method for treating a substrate (hereinafter, also referred to as "the substrate treatment method of the present disclosure") including the following Step 1, Step 2, and Step 3. Step 1: Treating a substrate having a resin mask with a treatment liquid obtained by mixing an aqueous solution (Solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine and an aqueous solution (Solution B) containing an organic solvent and an alkanolamine Step 2: Determining the concentration of carbonate ions (carbonic acid concentration) in the treatment liquid (Solution C) after use in Step 1 Step 3: Calculating the amount of alkanolamine contained in Solution A containing the same amount of aliphatic quaternary ammonium hydroxide as that consumed for neutralizing the carbonic acid in Solution C from the carbonic acid concentration in the treatment liquid (Solution C) determined in Step 2

[0015] According to the present disclosure, it is possible to provide a substrate treatment method excellent in resin mask peelability (removability) including a step of calculating a new index for preparing a recycled treatment liquid. By using the substrate treatment method of the present disclosure, high-quality electronic components can be obtained with a high yield.

[0016] In the present disclosure, the resin mask is a mask for protecting the surface of a substance from processes such as etching, plating, and heating, that is, a mask functioning as a protective film. Examples of the resin mask include, in one or more embodiments, a resist layer after exposure and development processes, a resist layer subjected to at least one of exposure and development processes (hereinafter, also referred to as "exposed and / or developed"), or a cured resist layer. In addition, in one or more embodiments, the resin mask is formed using a resist whose physical properties such as solubility in a developer change by light, an electron beam, or the like. Resists are broadly classified into negative resists and positive resists according to the reaction method with light or an electron beam. A negative resist has the property that its solubility in a developer decreases when exposed, and in a layer containing a negative resist (hereinafter, also referred to as a "negative resist layer"), the exposed portion is used as a resin mask after exposure and development processing. A positive resist has the property that its solubility in a developer increases when exposed, and in a layer containing a positive resist (hereinafter, also referred to as a "positive resist layer"), the exposed portion is removed after exposure and development processing, and the unexposed portion is used as a resin mask. By using a resin mask having such characteristics, fine connection portions of a circuit board such as metal wiring, metal pillars, and solder bumps can be formed. Examples of the resin material for forming the resin mask include a film-shaped photosensitive resin, a resist film, or a photoresist in one or more embodiments. General-purpose resist films can be used.

[0017] [Step 1] In one or more embodiments, Step 1 in the substrate processing method of the present disclosure is a step of processing a substrate having a resin mask using a treatment liquid obtained by using an aqueous solution (liquid A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine. In other one or more embodiments, Step 1 is a step of processing a substrate having a resin mask using a treatment liquid obtained by mixing an aqueous solution (liquid A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine with an aqueous solution (liquid B) containing an organic solvent and an alkanolamine.

[0018] <Liquid A> Liquid A is an aqueous solution containing an aliphatic quaternary ammonium hydroxide and an alkanolamine, and in one or more embodiments, optionally contains optional components (other components described later). Solution A can be obtained in one or more embodiments by combining an aliphatic quaternary ammonium hydroxide, an alkanolamine, water, and optionally other components (other components described later) in a known manner. Here, "combining" includes mixing the aliphatic quaternary ammonium hydroxide, alkanolamine, water, and optionally other components (other components described later) simultaneously or in any order. As for how to prepare solution A, one may obtain an aqueous solution containing an aliphatic quaternary ammonium hydroxide and an alkanolamine, or one may prepare an aqueous solution containing an aliphatic quaternary ammonium hydroxide and an alkanolamine oneself. Solution A is a replenishment solution used in one or more embodiments to replenish the stripping agent composition components of the processing solution (Solution C) that have been depleted by use.

[0019] (Aliphatic quaternary ammonium hydroxide in solution A) Examples of aliphatic quaternary ammonium hydroxides contained in solution A include quaternary ammonium hydroxides represented by the following formula (II). The aliphatic quaternary ammonium hydroxide may be one type or a combination of two or more types. [ka] In the above equation (II), R 4 , R 5 , R 6 and R 7 Each of these groups is independently at least one selected from a methyl group, an ethyl group, a propyl group, a hydroxymethyl group, a hydroxyethyl group, and a hydroxypropyl group. Quaternary ammonium hydroxides represented by formula (II) are salts consisting of a quaternary ammonium cation and a hydroxide, and include, for example, at least one selected from tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide (choline), 2-hydroxyethyltriethylammonium hydroxide, 2-hydroxyethyltripropylammonium hydroxide, 2-hydroxypropyltrimethylammonium hydroxide, 2-hydroxypropyltriethylammonium hydroxide, 2-hydroxypropyltripropylammonium hydroxide, dimethylbis(2-hydroxyethyl)ammonium hydroxide, diethylbis(2-hydroxyethyl)ammonium hydroxide, dipropylbis(2-hydroxyethyl)ammonium hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide, tris(2-hydroxyethyl)ethylammonium hydroxide, tris(2-hydroxyethyl)propylammonium hydroxide, tetrakis(2-hydroxyethyl)ammonium hydroxide, and tetrakis(2-hydroxypropyl)ammonium hydroxide. Among these, tetramethylammonium hydroxide (TMAH) is preferred from the viewpoint of improving the peelability (removability) of the resin mask. From the viewpoint of improving the peelability (removability) of the resin mask, the content of aliphatic quaternary ammonium hydroxide in solution A is preferably 2% by mass or more, more preferably 10% by mass or more, and even more preferably 20% by mass or more. Similarly, from the same viewpoint, it is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less. More specifically, the content of aliphatic quaternary ammonium hydroxide in solution A is preferably 2% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 40% by mass or less, and even more preferably 20% by mass or more and 30% by mass or less. If there is a combination of two or more aliphatic quaternary ammonium hydroxides, the content of aliphatic quaternary ammonium hydroxide in solution A is the total content of those two or more.

[0020] (Alkanolamine in solution A) Examples of alkanolamines (amino alcohols) contained in solution A include compounds represented by the following formula (I). The alkanolamine may be one type or a combination of two or more types. [ka] In the above equation (I), R 1 R represents a hydrogen atom, a methyl group, an ethyl group, or an aminoethyl group. 2 R represents a hydrogen atom, a hydroxyethyl group, a hydroxypropyl group, a methyl group, or an ethyl group. 3 This represents a hydroxyethyl group or a hydroxypropyl group. Component A can be, for example, at least one selected from monoethanolamine (MEA), monoisopropanolamine, N-methylmonoethanolamine, N-methylisopropanolamine, N-ethylmonoethanolamine, N-ethylisopropanolamine, diethanolamine, diisopropanolamine, N-dimethylmonoethanolamine, N-dimethylmonoisopropanolamine, N-methyldiethanolamine, N-methyldiisopropanolamine, N-diethylmonoethanolamine, N-diethylmonoisopropanolamine, N-ethyldiethanolamine, N-ethyldiisopropanolamine, N-(β-aminoethyl)ethanolamine, N-(β-aminoethyl)isopropanolamine, N-(β-aminoethyl)diethanolamine, and N-(β-aminoethyl)diisopropanolamine. Among these, monoethanolamine (MEA) is preferred from the viewpoint of improving the peelability (removability) of the resin mask. When the liquid A contains an alkanolamine, the content of the alkanolamine in the liquid A is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more from the viewpoint of improving the resin mask peelability (removability). And from the viewpoints of improving the resin mask peelability (removability) and substrate damage, it is preferably 80% by mass or less, more preferably 75% by mass or less, still more preferably 50% by mass or less. More specifically, the content of the alkanolamine in the liquid A is preferably 1% by mass or more and 80% by mass or less, more preferably 3% by mass or more and 75% by mass or less, still more preferably 5% by mass or more and 50% by mass or less. When the alkanolamine is a combination of two or more kinds, the content of the alkanolamine in the liquid A is the total content thereof.

[0021] (Water in liquid A) The content of water in the liquid A is preferably 10% by mass or more, more preferably 30% by mass or more, still more preferably 50% by mass or more from the viewpoint of improving the resin mask peelability (removability). And from the same viewpoint, it is preferably 95% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less. More specifically, the content of water in the liquid A is preferably 10% by mass or more and 95% by mass or less, more preferably 30% by mass or more and 85% by mass or less, still more preferably 50% by mass or more and 80% by mass or less.

[0022] (Other components in liquid A) In one or more embodiments, the liquid A may further contain other components. Examples of the other components include components that can be used in ordinary detergents, for example, alkali agents other than the above-mentioned alkanolamines and aliphatic quaternary ammonium hydroxides, amines other than the above-mentioned alkanolamines, organic solvents, surfactants, chelating agents, thickeners, dispersants, rust inhibitors, polymer compounds, solubilizers, antioxidants, preservatives, antifoaming agents, antibacterial agents, etc. In one or more embodiments, the liquid A does not contain an inhibitor.

[0023] <Liquid B> In one or more embodiments, solution B is an aqueous solution containing an organic solvent and an alkanolamine, and may further contain optional components (inhibitors, alkali metal hydroxides, and other components) as described later. Solution B can be obtained in one or more embodiments by combining an organic solvent, an alkanolamine, water, and optionally other components (inhibitors, alkali metal hydroxides, and other components) as described below, in a known manner. Here, "combining" includes mixing the organic solvent, alkanolamine, water, and optionally other components (inhibitors, alkali metal hydroxides, and other components) as described below, either simultaneously or in any order. As for how to prepare solution B, one may obtain an aqueous solution containing an organic solvent and an alkanolamine, or one may prepare an aqueous solution containing an organic solvent and an alkanolamine oneself. Solution B is a replenishment solution used in one or more embodiments to replenish the stripping agent composition components of the processing solution (Solution C) that have been depleted by use.

[0024] (Organic solvent in solution B) The organic solvent contained in solution B is preferably a ketone or alcohol compound, more preferably a glycol ether, and even more preferably butyl diglycol (BDG), from the viewpoint of improving the peelability (removability) of the resin mask. The organic solvent may be one type or a combination of two or more types. If solution B contains an organic solvent, the content of the organic solvent in solution B is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, and from the viewpoint of stability and miscibility, preferably 60% by mass or less, more preferably 55% by mass or less, and even more preferably 50% by mass or less. More specifically, the content of the organic solvent in solution B is preferably 10% by mass or more and 60% by mass or less, more preferably 15% by mass or more and 55% by mass or less, and even more preferably 20% by mass or more and 50% by mass or less. If the organic solvent is a combination of two or more types, the content of the organic solvent in solution B refers to the total content of those organic solvents.

[0025] (Alkanolamine in solution B) Examples of alkanolamines contained in solution B include the alkanolamines contained in solution A as described above. From the viewpoint of stability and miscibility, the content of alkanolamine in solution B is preferably 15% by mass or more, more preferably 25% by mass or more, and even more preferably 35% by mass or more. Similarly, from the viewpoint of stability and miscibility, it is preferably 60% by mass or less, more preferably 55% by mass or less, and even more preferably 50% by mass or less. More specifically, the content of alkanolamine in solution B is preferably 15% by mass or more and 60% by mass or less, more preferably 25% by mass or more and 55% by mass or less, and even more preferably 35% by mass or more and 50% by mass or less. If there is a combination of two or more alkanolamines, the content of alkanolamine in solution B is the total content of those alkanolamines.

[0026] (Water in solution B) Examples of the water contained in solution B include ion-exchanged water, RO water, distilled water, pure water, and ultrapure water. From the viewpoint of stability and miscibility, the water content in liquid B is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more. Similarly, from the viewpoint of stability and miscibility, it is preferably 70% by mass or less, more preferably 40% by mass or less, and even more preferably 20% by mass or less. More specifically, the water content in liquid B is preferably 5% by mass or more and 70% by mass or less, more preferably 10% by mass or more and 40% by mass or less, and even more preferably 15% by mass or more and 20% by mass or less.

[0027] (Inhibitor in solution B) In one or more embodiments, solution B may further contain an inhibitor. Examples of inhibitors contained in solution B include compounds containing heteroatoms, specifically nitrogen, sulfur, and oxygen atom compounds. More specifically, examples include azoles, and even more specifically, at least one selected from pyrazole, methylpyrazole, thiazole, oxazole, triazole, benzotriazole, tolyltriazole, dimethylbenzotriazole, tetrazole, triazine, tetrazine, pentazole, imidazole, methylimidazole, phenylimidazole, and dimethylbenzimidazole. Among these, from the viewpoint of improving resin mask peelability (removability), at least one inhibitor selected from triazole, benzotriazole, tolyltriazole, dimethylbenzimidazole is preferred, and at least one selected from benzotriazole, imidazole, and dimethylbenzimidazole is more preferred. The inhibitor may be one type or a combination of two or more types. From the viewpoint of etching suppression, the inhibitor content in solution B is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.5% by mass or more. Similarly, from the same viewpoint, it is preferably 6% by mass or less, more preferably 3% by mass or less, and even more preferably 1.5% by mass or less. More specifically, the inhibitor content in solution B is preferably 0.05% by mass or more and 6% by mass or less, more preferably 0.1% by mass or more and 3% by mass or less, and even more preferably 0.5% by mass or more and 1.5% by mass or less. If there is a combination of two or more inhibitors, the inhibitor content in solution B is the total content of those inhibitors.

[0028] (Alkali metal hydroxide in solution B) In one or more embodiments, solution B may further contain an alkali metal hydroxide. From the viewpoint of improving the peelability (removability) of the resin mask, the alkali metal hydroxide contained in solution B is preferably at least one selected from lithium hydroxide, sodium hydroxide, and potassium hydroxide, more preferably at least one of sodium hydroxide and potassium hydroxide, and even more preferably potassium hydroxide. The alkali metal hydroxide may be one type or a combination of two or more types. If solution B contains alkali metal hydroxides, the alkali metal hydroxide content in solution B is preferably 0.3% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, and from the viewpoint of stability and miscibility, preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less. More specifically, the alkali metal hydroxide content in solution B is preferably 0.3% by mass or more and 10% by mass or less, more preferably 1% by mass or more and 8% by mass or less, and even more preferably 2% by mass or more and 5% by mass or less. If the alkali metal hydroxides are a combination of two or more types, the alkali metal hydroxide content in solution B refers to their total content.

[0029] (Other components in Solution B) In one or more embodiments, solution B may further contain other components. Examples of other components include those commonly used in cleaning agents, such as alkaline agents other than the alkanolamines and alkali metal hydroxides mentioned above, amines other than the alkanolamines mentioned above, organic solvents other than the organic solvents mentioned above, surfactants, chelating agents, thickeners, dispersants, rust inhibitors, polymer compounds, solubilizers, antioxidants, preservatives, defoaming agents, and antibacterial agents.

[0030] <Processing solution> The treatment solution can be obtained using solution A in one or more embodiments and may include, for example, an aliphatic quaternary ammonium, an alkanolamine, water, and optionally other components (inhibitors, alkali metal hydroxides, organic solvents, and other components) as described below. In one or more other embodiments, the treatment solution is a mixture obtained by mixing solution A and solution B, and includes, for example, an aliphatic quaternary ammonium, an alkanolamine, an organic solvent, water, and optionally other components (inhibitors, alkali metal hydroxides, and other components) as described later. The treatment solution can be obtained in one or more embodiments by combining an aliphatic quaternary ammonium, an alkanolamine, water, and optionally other components (inhibitors, alkali metal hydroxides, organic solvents, and other components) as described below, in a known manner. Here, "combining" includes mixing the alkanolamine, water, and optionally other components (inhibitors, alkali metal hydroxides, organic solvents, and other components) simultaneously or in any order. A known mixing method can be used, and the mixing conditions can be set as appropriate.

[0031] In one or more embodiments, the processing liquid is a processing liquid for use in processing a substrate having a resin mask, a resin mask removal cleaning agent composition for cleaning a substrate having a resin mask, or a removal agent composition for removing a resin mask from a substrate having a resin mask.

[0032] (Aliphatic quaternary ammonium hydroxide in the treatment solution) The aliphatic quaternary ammonium hydroxide contained in the aforementioned treatment solution is an example of the aliphatic quaternary ammonium hydroxide contained in solution A described above. From the viewpoint of improving the peelability (removability) of the resin mask, the content of aliphatic quaternary ammonium hydroxide in the treatment solution is preferably 0.5% by mass or more, more preferably 1.5% by mass or more, and even more preferably 3% by mass or more. From the same viewpoint, it is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 7% by mass or less. More specifically, the content of aliphatic quaternary ammonium hydroxide in the treatment solution is preferably 0.5% by mass or more and 15% by mass or less, more preferably 1.5% by mass or more and 10% by mass or less, and even more preferably 3% by mass or more and 7% by mass or less. When there is a combination of two or more aliphatic quaternary ammonium hydroxides, the content of aliphatic quaternary ammonium hydroxide in the treatment solution refers to the total content of those aliphatic quaternary ammonium hydroxides.

[0033] (Alkanolamines in the treatment solution) Examples of alkanolamines contained in the aforementioned processing solution include the aliphatic alkanolamines contained in solution A described above. From the viewpoint of improving the peelability (removability) of the resin mask, the content of alkanolamine in the treatment solution is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more. From the same viewpoint, it is preferably 18% by mass or less, more preferably 15% by mass or less, and even more preferably 12% by mass or less. More specifically, the content of alkanolamine in the treatment solution is preferably 3% by mass or more and 18% by mass or less, preferably 5% by mass or more and 15% by mass or less, and even more preferably 8% by mass or more and 12% by mass or less. If there is a combination of two or more alkanolamines, the content of alkanolamine in the treatment solution is the total content of those alkanolamines.

[0034] (Water in the processing solution) The water content in the processing solution can be the remainder after removing the above-mentioned components (aliphatic quaternary ammonium salts, alkanolamines, organic solvents, inhibitors, alkali metal hydroxides, and other components) from the entire processing solution. Specifically, from the viewpoint of improving the peelability (removability) of the resin mask, the water content in the processing solution is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, and from the same viewpoint, preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less.

[0035] (Organic solvent in the processing solution) The organic solvent contained in the processing solution is the organic solvent contained in solution B described above. If the processing solution contains an organic solvent, the content of the organic solvent in the processing solution is preferably 2% by mass or more, more preferably 4% by mass or more, even more preferably 10% by mass or more, and from the viewpoint of improving the peelability (removability) of the resin mask, preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less. More specifically, the content of the organic solvent in the processing solution is preferably 2% by mass or more and 25% by mass or less, more preferably 4% by mass or more and 20% by mass or less, and even more preferably 10% by mass or more and 15% by mass or less. If the organic solvent is a combination of two or more types, the content of the organic solvent in the processing solution refers to the total content of those organic solvents.

[0036] (Inhibitors in the treatment solution) Examples of inhibitors contained in the aforementioned processing solution include the inhibitors contained in the above-mentioned solution B. If the processing solution contains an inhibitor, the inhibitor content in the processing solution is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, even more preferably 0.05% by mass or more, and from the same viewpoint, preferably 3% by mass or less, more preferably 1% by mass or less, and even more preferably 0.5% by mass or less. More specifically, the inhibitor content in the processing solution is preferably 0.01% by mass or more and 3% by mass or less, more preferably 0.02% by mass or more and 1% by mass or less, and even more preferably 0.05% by mass or more and 0.5% by mass or less. If the inhibitor is a combination of two or more types, the inhibitor content in the processing solution is the total content of those types.

[0037] (Alkali metal hydroxides in the treatment solution) Examples of alkali metal hydroxides contained in the aforementioned processing solution include the alkali metal hydroxides contained in solution B described above. If the processing solution contains alkali metal hydroxides, the alkali metal hydroxide content in the processing solution is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, even more preferably 0.5% by mass or more, and from the viewpoint of improving the peelability (removability) of the resin mask, preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1.5% by mass or less. More specifically, the alkali metal hydroxide content in the processing solution is preferably 0.1% by mass or more and 3% by mass or less, more preferably 0.2% by mass or more and 2% by mass or less, and even more preferably 0.5% by mass or more and 1.5% by mass or less. If the alkali metal hydroxides are a combination of two or more types, the alkali metal hydroxide content in the processing solution refers to their total content.

[0038] (Other components in the processing solution) The processing solution may further contain other components in one or more embodiments. Examples of other components include those that can be used in ordinary cleaning agents (stripping agents), such as alkaline agents other than the alkanolamines and alkali metal hydroxides mentioned above, amines other than the alkanolamines mentioned above, organic solvents other than the organic solvents mentioned above, surfactants, chelating agents, thickeners, dispersants, rust inhibitors, polymer compounds, solubilizers, antioxidants, preservatives, defoaming agents, antibacterial agents, and the like.

[0039] In this disclosure, "content of each component in the processing solution" means the content of each component at the time of use, that is, at the time when the processing solution is first used for substrate processing (resin mask peeling treatment). In this disclosure, the content of each component in the processing solution can be considered as the amount of each component blended in the processing solution in one or more embodiments.

[0040] (pH of the treatment solution) The pH of the processing solution is preferably 10 or higher, more preferably 11 or higher, and even more preferably 12 or higher, from the viewpoint of improving the peelability (removability) of the resin mask, and preferably 15 or lower, more preferably 14.7 or lower, and even more preferably 14.5 or lower, from the viewpoint of suppressing damage to the substrate resin. In this disclosure, the pH of the processing solution is the value at 25°C and can be measured using a pH meter, and specifically can be measured by the method described in the examples.

[0041] <Object to be processed> In one or more embodiments, the object to be processed is a substrate having a resin mask. Examples of the substrate include printed circuit boards, wafers, copper plates, aluminum plates, and the like. The resin mask may be, for example, a negative-type resin mask or a positive-type resin mask, and a negative-type resin mask is preferred because it is easier to achieve the effects of this disclosure. An example of a negative-type resin mask is an exposed and / or developed negative-type dry film resist. In the present disclosure, the negative-type resin mask is formed using a negative-type resist, and examples thereof include a negative-type resist layer that has been subjected to exposure and / or development processing. In the present disclosure, the positive-type resin mask is formed using a positive-type resist, and examples thereof include a positive-type resist layer that has been subjected to exposure and / or development processing. Examples of the thickness of the resin mask include 5 μm to 35 μm or less.

[0042] Examples of the substrate (object to be cleaned) having the resin mask include, in one or more embodiments, a substrate having a metal layer and a resin mask on its surface. In one or more embodiments, the metal layer is a copper plating layer. The copper plating layer can be formed, for example, by an electrolytic copper plating method. Examples of the thickness of the metal layer include 3 μm or more and 30 μm or less. In one or more embodiments, the metal layer is used as a metal wiring or a wiring connection portion. In one or more embodiments, examples of the resin mask include a resin mask (resin mask layer) that exists in a perforated shape on the metal layer (see FIG. Ⅰ). In one or more embodiments, the side surface of the resin mask is surrounded by the metal layer. In one or more embodiments, examples of the shape of the resin mask layer include polygonal (square, hexagonal, octagonal, etc.) columnar, cylindrical, substantially cylindrical, etc. Examples of the diameter of the resin mask layer (the diameter of the circumscribed circle in the case of a polygon) include 20 μm or more and 200 μm or less. Examples of the thickness of the resin mask layer include 5 μm or more and 50 μm or less. The interface ratio (μm - )(= the interface line length (μm) between the resin mask and the metal layer / the area (μm 2 )) of the resin mask existing in a perforated shape is 0.01 or more and 0.5 or less, or 0.02 or more and 0.2 or less. Here, the interface line length between the resin mask and the metal layer is, for example, the circumference length when the resin mask is circular when viewed from above. A new problem has been discovered with objects to be cleaned that have a resin mask of this structure: the peelability of conventional peeling agents is reduced. The processing liquid used in step 1 and the reuse processing liquid described later can suitably peel off resin masks of this structure in one or more embodiments. In one or more embodiments, the object to be cleaned in which at least one resin mask, which is present in a perforated manner on a metal layer as described above, is attached is an object to be cleaned.

[0043] In one or more embodiments, the substrate (workpiece) having the resin mask includes a substrate having a metal layer and a resin mask on its surface. In one or more embodiments, the metal layer is a copper plating layer. The copper plating layer can be formed, for example, by an electrolytic copper plating method. Examples of the thickness of the metal layer include 3 μm to 30 μm. In one or more embodiments, the metal layer is used as metal wiring or wiring connection.

[0044] In one or more other embodiments, the substrate (workpiece) having the resin mask may include, for example, an electronic component having a metal layer and a resin mask on its surface and an intermediate product of the same. Examples of electronic components include at least one component selected from printed circuit boards, wafers, copper plates, and aluminum plates. The intermediate product is an intermediate product in the manufacturing process of an electronic component, and includes an intermediate product after resin mask processing. Specific examples of objects to be processed include, for example, electronic components on which wiring, connection terminals, etc., are formed on the substrate surface by undergoing a process of at least one of the following: soldering using a resin mask and plating (copper plating, aluminum plating, nickel plating, tin plating, etc.). In this disclosure, soldering means creating solder in areas on the substrate where a resin mask is not present and forming solder bumps by heating. In this disclosure, plating means performing at least one plating process selected from copper plating, aluminum plating, nickel plating, and tin plating on areas on the substrate where a resin mask is not present. Areas where a resin mask is not present refer to the parts of a resist pattern (a resin mask in the shape of a pattern) formed by phenotyping a resin mask laminated to a substrate, where the resin mask has been removed by phenotyping.

[0045] In one or more other embodiments, the substrate (workpiece) having the resin mask includes a substrate having a resin mask in a fine gap. An example of a substrate having a resin mask in a fine gap is a substrate in which a non-cured resin mask is subjected to curing treatment of at least one of exposure and development on the substrate surface, the non-cured resin mask is removed, and then a circuit pattern is formed by plating. The hardened resin mask is present in the non-plated portion of the formed circuit pattern. In this disclosure, a gap refers to the distance between circuit patterns (fine wire sections) (the distance between adjacent fine wire sections) in one or more embodiments, and is also called space (S). The thickness (plating thickness) of the fine wire section is, for example, 3 μm or more and 30 μm or less. The width of the fine wire section is also called line (L). A resin mask in a fine gap refers to a resin mask that exists in a space with a space width (S) of 10 μm or less in one or more embodiments. The thickness of the resin mask is, for example, 5 μm or more and 35 μm or less. An example of a resin mask in a fine gap is a resin mask that exists in a space with a space width (S) of 4 to 7 μm.

[0046] <Processing> In one or more embodiments, step 1 includes a step (processing step) of processing a substrate (object to be processed) having a resin mask using a processing liquid. In one or more embodiments, the process includes cleaning the substrate having the resin mask, peeling the resin mask off the substrate having the resin mask, and removing the resin mask from the substrate having the resin mask. In one or more embodiments, the processing step includes bringing the processing liquid into contact with the object to be processed.

[0047] In this disclosure, examples of methods for peeling a resin mask from an object to be treated using a processing liquid, or for bringing the processing liquid into contact with an object to be treated, include immersing the object in a washing bath containing the processing liquid, spraying the processing liquid into contact with the object (shower method), and ultrasonic cleaning methods that involve ultrasonic irradiation while the object is immersed in the processing liquid. The processing solution in this disclosure can be used directly for cleaning without dilution. Examples of materials to be processed include those mentioned above. For example, in one or more embodiments, the processing step includes spraying the processing solution obtained in the mixing step onto a substrate (workpiece) having a resin mask. Examples of the time during which the processing liquid is in contact with or immersed in the object to be processed (contact time or immersion time) include 1 minute or more and 10 minutes or more, and 2 minutes or more and 6 minutes or less. When the processing liquid is sprayed and brought into contact with the surface, the spray time can be, for example, between 1 minute and 10 minutes, or between 2 minutes and 6 minutes.

[0048] In the aforementioned processing step, it is preferable to irradiate the object to be processed with ultrasound when the processing liquid comes into contact with the object, in order to easily exhibit the peeling and cleaning power of the processing liquid (resin mask peeling ability, resin mask removal ability), and it is more preferable that the ultrasound is of a relatively high frequency. From the same viewpoint, the irradiation conditions for the ultrasound are preferably, for example, 26 to 72 kHz and 80 to 1500 W, and more preferably 36 to 72 kHz and 80 to 1500 W.

[0049] In the aforementioned processing step, the temperature at which the processing solution is used (processing temperature) is preferably 40°C or higher, more preferably 50°C or higher, and more preferably 70°C or lower, and more preferably 60°C or lower, from the viewpoint of reducing the impact on the substrate.

[0050] In one or more embodiments, the processing step may further include bringing the object to be processed into contact with the processing liquid obtained in the mixing step, rinsing with water, and drying. Examples of rinsing methods include running water rinsing. Examples of drying methods include air blow drying. In one or more embodiments, the processing step may further include bringing the object to be processed into contact with the processing liquid obtained in the mixing step, and then rinsing it with water.

[0051] [Step 2: Carbonation Concentration] Step 2 in the substrate processing method of this disclosure is a step of determining the concentration of carbonate ions (carbonate concentration) in the processing solution (Solution C) used in Step 1. Methods for determining the carbon dioxide concentration include, in one or more embodiments, measuring the carbon dioxide concentration in the processing solution after use, and calculating it from the number of substrates processed. Calculating from the number of substrates processed can be done, for example, by considering the number of substrates processed, the time required to process one substrate, and the increase in carbon dioxide concentration per unit time.

[0052] (Carbon dioxide in solution C) In this disclosure, liquid C is a processing liquid (stripping agent composition) in which carbon dioxide is dissolved in the processing liquid during the processing step or circulation, and which contains carbon dioxide (carbonate ions). In one or more embodiments, the carbon dioxide (carbonate ions) contained in the processing solution (Solution C) after use in Step 1 originates from carbon dioxide gas in the air. The carbon dioxide concentration (content) in solution C is generally preferable to be as low as possible from the viewpoint of improving the peelability (removability) of the resin mask. For example, the carbon dioxide concentration (content) in the treatment solution is preferably 10 ml / L or less, more preferably 5 ml / L or less, even more preferably 1 ml / L or less, and 0.1 ml / L or more from the viewpoint of improving the peelability (removability) of the resin mask. In this disclosure, the carbon dioxide concentration in the treatment solution can be measured using potentiometric titration.

[0053] The molar ratio of aliphatic quaternary ammonium hydroxide to carbonate ions in the aforementioned solution C (aliphatic quaternary ammonium hydroxide / carbonate ions) is preferably 0.01 or higher, more preferably 0.1 or higher, and even more preferably 1 or higher, and from the viewpoint of improving the peelability (removability) of the resin mask, it is preferably 100 or lower, more preferably 30 or lower, and even more preferably 10 or lower. More specifically, the molar ratio (aliphatic quaternary ammonium hydroxide / carbonate ions) in the aforementioned solution C is preferably 0.01 or higher and 100 or lower, more preferably 0.1 or higher and 30 or lower, and even more preferably 1 or higher and 10 or lower.

[0054] [Step 3: Calculation of the amount of alkanolamine] Step 3 in the substrate processing method of this disclosure is a step of calculating the amount of alkanolamine contained in solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in solution C, based on the carbon dioxide concentration in the processing solution (solution C) determined in step 2. In one or more embodiments, this amount of alkanolamine can also be the amount of alkanolamine brought in from solution A to neutralize the carbon dioxide in solution C. The unit of this amount of alkanolamine may be concentration or mass. As will be described later, this amount of alkanolamine can be used when preparing a reused processing solution from used solution C.

[0055] Step 3 includes, in one or more embodiments, calculating the amount of the alkanolamine using the following formula (I). Amount of alkanolamine (mass%) = [Carbonate concentration in solution C (mol / L) × C × Molar mass of aliphatic quaternary ammonium hydroxide (g / mol)] ÷ Amount of aliphatic quaternary ammonium hydroxide in solution A (mass%) × Amount of alkanolamine in solution A (mass%) (I) However, in formula (I) above, the coefficient C is a coefficient determined based on the degree of neutralization, the number of neutralization additions, and the unit conversion coefficient, and is a value in the range of 0.01 to 1. The coefficient C is defined in one or more embodiments as the degree of neutralization × the number of additions × the unit conversion factor. The coefficient C is, in one or more embodiments, the number of aliphatic quaternary ammonium ions added to the carbonate ion, and can be determined by the valencies of the carbonate and aliphatic quaternary ammonium hydroxide. The degree of neutralization is 0 to 1 in one or more embodiments, and is usually 1. The neutralization addition number is the valency of the acid divided by the valency of the alkali of the aliphatic quaternary ammonium hydroxide, and in one or more embodiments, it is between 0 and 5, and is usually 2. The unit conversion factor is, for example, 0.1 when converting from g / L to mass%. For example, if the aliphatic quaternary ammonium hydroxide is TMAH, the degree of neutralization is 1, the number of additions is 2, and the unit conversion factor (when converting g / L to mass%) is 0.1, so the coefficient C = 0.2 can be used in equation (I).

[0056] [Step 4: Preparation of recycled treatment liquid] In one or more embodiments, the substrate processing method of the present disclosure includes a step 4: mixing solution A with solution C based on the amount of alkanolamine calculated in step 3 to prepare a reuse processing solution. In one or more embodiments, step 4 further includes a step of mixing solution B with solution C based on the amount of alkanolamine calculated in step 3. In one or more embodiments, step 4 includes processing a substrate having a resin mask using the reuse processing solution.

[0057] <Recycled treatment liquid> The recycled treatment liquid is, in one or more embodiments, a mixture obtained by mixing liquid A and liquid C, and in one or more other embodiments, a mixture obtained by mixing liquid A, liquid B, and liquid C. The components contained in the recycled treatment liquid are the same as those in the treatment liquid described above. The preferred content of each component in the recycled treatment liquid is the same as the preferred content of each component in the treatment liquid described above. In one or more embodiments, the carbonate ions (carbonic acid) contained in the recycled treatment liquid originate from carbon dioxide gas in the air, etc. Generally, a lower carbon dioxide concentration (content) in the recycled treatment liquid is preferable from the viewpoint of improving the peelability (removability) of the resin mask. For example, from the viewpoint of improving the peelability (removability) of the resin mask, the carbon dioxide concentration (content) in the recycled treatment liquid is preferably 10 mol / L or less, more preferably 5 mol / L or less, even more preferably 1.1 mol / L or less, even more preferably 1 mol / L or less, and 0.1 mol / L or more.

[0058] <Mixing conditions> In step 4, known methods can be used for mixing solution A with solution C, mixing solution B with solution C, and mixing solution A, solution B, and solution C. The mixing conditions (the mixing ratio of solution C to solution A, the mixing ratio of solution C to solution B, and the mixing ratio of solution A, solution B, and solution C) can be set in one or more embodiments based on the amount of alkanolamine calculated in step 3. In this disclosure, mixing in one or more embodiments includes adding one to the other. For example, the settings are configured such that the sum of the differences between the concentrations of the amine, aliphatic quaternary ammonium hydroxide, and organic solvent in the mixed alkanolamine and the target values ​​is minimized. In step 4, in one or more embodiments, the mixing ratio of solution C to solution A, the mixing ratio of solution C to solution B, or the mixing ratio of solution A, solution B, and solution C can be determined based on the amount of alkanolamine calculated in step 3, and the amount of solution A to be replenished or the amount of solution B to be replenished can be controlled. Here, "mixing solution A with solution C based on the amount of alkanolamine calculated in step 3" means, in one or more embodiments, a method of mixing solution A with solution C at a ratio determined by the difference, ratio, and correction coefficient between the amount of alkanolamine in the processing solution (solution C) used in step 1 and the amount of alkanolamine calculated in step 3. Furthermore, "mixing solution B with solution C based on the amount of alkanolamine calculated in step 3" refers to a method in which, in one or more embodiments, solution B contains an amount of monoethanolamine obtained by subtracting the amount of alkanolamine calculated in step 3 from the difference between the target concentration of alkanolamine and the concentration of the processing solution (solution C) used in step 1, and mixing that amount with solution C.

[0059] Step 4 may further include, in one or more embodiments, changing at least one of the following based on the amount of alkanolamine calculated in Step 3: the time the treatment solution is in contact with or immersed in the object to be treated, and the temperature of the treatment solution during use.

[0060] [Step 5: Recovery] The substrate processing method of the present disclosure may further include step 5 (recovery step) in one or more embodiments. Step 5 in the substrate processing method of the present disclosure is a step of recovering the processing liquid used in step 1. In one or more embodiments, at least a portion of the processing liquid recovered in the process can be reused as a processing liquid after going through steps 2 to 4. Therefore, in the substrate treatment method of this disclosure, in one or more embodiments, the processing liquid recovered in step 5 can be recycled and reused.

[0061] [Removal Method] This disclosure relates, in one embodiment, to a method for peeling off a resin mask (hereinafter also referred to as "the peeling method of this disclosure"), which includes peeling off a resin mask from a substrate (workpiece to be processed) having a resin mask using the substrate processing method of this disclosure. Examples of workpieces to be processed in the peeling method of this disclosure include the cleaning workpieces mentioned above. The peeling method of this disclosure provides a resin mask peeling method with excellent resin mask removal (peeling ability), which includes a step of calculating a new index for preparing a reuse processing liquid.

[0062] [Management method for processing solution (strip agent composition)] This disclosure relates, in one embodiment, to a method for managing a processing solution (release agent composition) used in a process of processing a substrate having a resin mask (workpiece to be processed) using a processing solution obtained using an aqueous solution (Solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine (Solution A). In one or more embodiments, the control method of the present disclosure includes: step a (step 2 in the substrate processing method of the present disclosure described above) determining the carbon dioxide concentration in the processing solution (solution C) used to process the workpiece; and step b (step 3 in the substrate processing method described above) calculating the amount of alkanolamine contained in solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in solution C, from the carbon dioxide concentration in the processing solution (solution C) determined in step a. In one or more embodiments, the management method of the present disclosure includes step c (step 4 in the substrate processing method described above), which is a step of mixing solution A with solution C based on the amount of alkanolamine calculated in step b to prepare a reuse processing solution. In one or more embodiments, step c further includes a step of mixing an aqueous solution (solution B) containing an organic solvent and alkanolamine with solution C based on the amount of alkanolamine calculated in step b. According to the management method disclosed herein, when replenishing an alkaline stripping agent composition containing carbonate ions (processing solution after use) (solution C) with an aqueous solution containing aliphatic quaternary ammonium hydroxide and an alkanolamine (solution A), the amount of aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbonate can be calculated from the carbon dioxide concentration in the processing solution after use in substrate processing. The preparation of the reused processing solution can then be managed by considering a new indicator: the amount of alkanolamine contained in solution A that corresponds to the amount of aliphatic quaternary ammonium hydroxide. This makes it possible to obtain a reused processing solution with excellent resin mask stripping (removal) properties.

[0063] [Manufacturing methods for electronic components] This disclosure relates, in one embodiment, to a method for manufacturing an electronic component substrate, including the substrate processing method of this disclosure. The method for manufacturing electronic components described herein allows for the effective removal of resin masks adhering to substrates, thereby enabling the manufacture of highly reliable electronic components. Furthermore, by using the substrate processing method described herein, the resin masks adhering to substrates can be easily peeled off, shortening the peeling time (processing time) and improving the manufacturing efficiency of electronic components. [Examples]

[0064] The present disclosure will be specifically described below with reference to examples, but the present disclosure is not limited in any way by these examples.

[0065] Test 1 (Example 1, Reference Example 1) 1-1. Preparation of the used treatment solution (Solution C) Alkanolamine (MEA), a carbon dioxide source (ammonium carbonate), and water were mixed to obtain solution D shown in Table 1. The ammonium carbonate, which is the carbon dioxide source in solution D, produces carbonate ions in aqueous solution. The carbon dioxide in solution D shown in Table 1 represents the carbonate ions produced from ammonium carbonate. Aliphatic quaternary ammonium hydroxide (TMAH), alkanolamine (MEA), and water were mixed to obtain solution A shown in Table 1. Solution D and Solution A were mixed over 1 hour in the mixing ratios shown in Table 1 to obtain Solution C (used treatment solution) (pH: 11.9) shown in Table 1. In Solution C, a portion of TMAH reacts with carbonate (ions) to form a neutralizing salt. Solution C, which contains this neutralizing salt, is intended to represent the treatment solution used in Step 1. The concentrations (amounts) (mass% or mol / L, effective content) of each component in Solution D and Solution A before mixing are shown in Table 1. The concentrations listed in Table 1 are the active ingredient concentrations (mass% or mol / L) calculated from the amounts used.

[0066] The following materials were used to prepare solutions D and A. MEA: Monoethanolamine [Nippon Shokubai Co., Ltd.] Ammonium carbonate [Fujifilm Wako Pure Chemical Industries] (carbon dioxide source) TMAH: Tetramethylammonium hydroxide [Resonac Co., Ltd., 25% aqueous solution] Water [Pure water with a purity of 1 μS / cm or less, produced using Organo's G-10DSTSET pure water production system]

[0067] [pH of the treatment solution] The pH of the treatment solution at 25°C was measured using a pH meter (Toa Denpa Kogyo Co., Ltd., HM-30G), and the value was obtained 3 minutes after immersing the pH meter's electrode in the treatment solution.

[0068] 1-2. Amount of alkanolamines (Example 1: Calculation of the amount of alkanolamine using formula (I) (Steps 2-3)) The amount of alkanolamine contained in solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in the neutralization of the carbon dioxide in solution C, was calculated from the carbon dioxide concentration in solution C as follows. First, calculate the carbon dioxide concentration in solution C using the following formula. Carbon dioxide concentration in solution C (mol / L) = Carbon dioxide concentration in solution C (mol / L) × Mixing ratio of solution C (%) ÷ 100 Next, using the mass ratio of aliphatic quaternary ammonium hydroxide to alkanolamine in solution A, the amount of alkanolamine in solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as consumed in the neutralization of carbonic acid, is calculated from the following formula (I). Amount of alkanolamine (mass%) = [Carbonate concentration in solution C (mol / L) × C × Molar mass of aliphatic quaternary ammonium hydroxide (g / mol)] ÷ Amount of aliphatic quaternary ammonium hydroxide in solution A (mass%) × Amount of alkanolamine in solution A (mass%) (I) In equation (I) above, the coefficient C is a coefficient determined based on the degree of neutralization, the number of neutralization additions, and the unit conversion factor, and is defined as the degree of neutralization (0 to 1, usually 1) × the number of neutralization additions (0 to 2, usually 2) × the unit conversion factor (0.1 when converting g / L to mass%). Here, the degree of neutralization is 1, the number of neutralization additions is 2, and the unit conversion factor is 0.1, so the coefficient C = 0.2 is used in equation (I).

[0069] (Reference Example 1: Calculation of alkanolamine amount by titration) The prepared treatment solution (Solution C) was titrated using a potentiometric automatic titrator (Kyoto Electronics Manufacturing Co., Ltd., AT-710) with a sample volume of 5 g and water (45 g) as the dilution solvent (dilution ratio: 10 times). A titration curve showing the relationship between the amount of acid added by titration and pH was obtained, and three inflection points derived from amines that appeared below pH 10 were detected. The three inflection points were detected as points where the first derivative of pH was minimal, and were designated as the 1st, 2nd, and 3rd inflection points in order of appearance. The concentration of alkanolamine in the treatment solution (Solution C) was then calculated using the formula described below. Alkanolamine concentration (mass%) = ((AD × β) + (BD × β)) / 2 / α × M × 100 In the above formula, A represents the number of moles of acid consumed per gram of the treatment solution (Solution C) up to the first inflection point (mol / g), B represents the number of moles of acid consumed per gram of the treatment solution (Solution C) up to the second inflection point (mol / g), D represents the concentration of alkalis other than the alkanolamine in the treatment solution (Solution C) (mol / g), α represents the valence of the alkanolamine, β represents the valence of alkalis other than the alkanolamine, and M represents the molar mass of the alkanolamine (g / mol).

[0070] [Table 1]

[0071] As shown in Table 1, in Example 1, the amount of alkanolamine contained in solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in the neutralization of carbonic acid in solution C, could be calculated using formula (I). On the other hand, this could not be calculated using the titration method of Reference Example 1.

[0072] Test 2 (Example 2) 2-1. Preparation of the used treatment solution (Solution C) Alkanolamine (MEA), organic solvent (BDG), carbon dioxide source (ammonium carbonate), and water were mixed to obtain solution D shown in Table 2. Ammonium carbonate, the carbon dioxide source in solution D, produces carbonate ions in aqueous solution. The carbon dioxide in solution D shown in Table 2 represents carbonate ions produced from ammonium carbonate. Aliphatic quaternary ammonium hydroxide (TMAH), alkanolamine (MEA), and water were mixed to obtain solution A shown in Table 2. Solution D and Solution A were mixed over 1 hour in the mixing ratios shown in Table 2 to obtain Solution C (used treatment solution) (pH: 11.9) shown in Table 2. The pH of the treatment solution was measured using the same method as in Test 1 above. In Solution C, a portion of TMAH reacts with carbonate (ions) to form a neutralized salt. Solution C, which contains this neutralized salt, is intended to represent the treatment solution used in Step 1. The concentrations (amounts) (mass% or mol / L, effective content) of each component in Solution D and Solution A before mixing are shown in Table 2. The concentrations listed in Table 2 are the active ingredient concentrations (mass% or mol / L) calculated from the amounts used.

[0073] The following materials were used to prepare solutions D and A. MEA: Monoethanolamine [Nippon Shokubai Co., Ltd.] BDG: Butyl diglycol [Nippon Emulsifier Co., Ltd.] Ammonium carbonate [Fujifilm Wako Pure Chemical Industries] (carbon dioxide source) TMAH: Tetramethylammonium hydroxide [Resonac Co., Ltd., 25% aqueous solution] Water [Pure water with a purity of 1 μS / cm or less, produced using Organo's G-10DSTSET pure water production system]

[0074] 2-2. Calculation of the amount of alkanolamine using formula (I) (Steps 2-3) Using the same method as in Example 1, the amount of alkanolamine in solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the amount consumed in neutralizing the carbon dioxide in solution C, was calculated from the carbon dioxide concentration in solution C. The calculation results are shown in Table 2. The amounts of alkanolamine in Table 2 are converted to mass percent.

[0075] 2-3. Preparation of recycled treatment liquid (Step 4) Based on the amount of alkanolamine calculated using formula (I) in 1-2 above, the mixing ratio of solution C, solution A, and solution B was determined using the following formula. Based on the determined mixing ratio, solution C, solution A, and solution B were mixed to prepare a recycled treatment solution. The mixing ratio (mass%) of solution C used in preparing the recycled treatment solution = [Amount of alkanolamine in solution C (mass%) - Amount of alkanolamine calculated using formula (I) (mass%) ÷ 2.5] ÷ Amount of alkanolamine in solution C (mass%) × 100 The mixing ratio (mass%) of solution A used in preparing the recycled treatment solution = Amount of alkanolamine calculated using formula (I) (mass%) ÷ Amount of alkanolamine in solution A (mass%) ÷ 3.5 × 100 Mixing ratio of water used in preparing the recycled treatment solution (mass%) = 100 - Mixing ratio of solution A used in preparing the recycled treatment solution (mass%) - Mixing ratio of solution C used in preparing the recycled treatment solution (mass%) In the above formula, 2.5 and 3.5 are coefficients set to minimize the sum of the differences in the concentrations of the amine, aliphatic quaternary ammonium hydroxide, and organic solvent of the mixed alkanolamine from the target values.

[0076] 2-4. Evaluation of the treatment solution The resin mask removal (peelability) was evaluated using the recycled treatment solution prepared in Example 2 as follows.

[0077] [Test piece for evaluating peelability] The test piece for evaluating peelability is 50 mm x 50 mm in size and, as shown in Figure 1, has a 15 μm thick metal layer 2 formed by copper plating on the surface of a glass epoxy multilayer substrate with a copper thin film, and a 25 μm thick negative-type dry film resist resin mask layer 1 in the circular areas with a diameter of 300 μm that exist as perforations in the metal layer 2, with 15 μm of the 25 μm thickness of the resin mask embedded in the metal layer. There are 3000 perforations. [Removability of resin mask (peelability)] Three kilograms of the release agent composition were added to a five-liter stainless steel beaker. This was heated to 50°C, and a test piece was sprayed for 2.5 minutes in a box-type spray cleaning machine equipped with a single-fluid nozzle (full cone type) J020 (Ikeuchi Co., Ltd.) as the spray nozzle, while circulating the solution (pressure: 0.05 MPa, spray distance: 8 cm). After rinsing with water for 30 seconds, the test piece was dried with a nitrogen blower. Using a digital microscope (VHX-6000, Keyence Corporation), the test piece after the spray treatment was visually observed at 300x magnification, and the rate of resin mask residue generation (residue rate) was measured. A lower value indicates better resin mask removal (peelability). The results are shown in Table 2.

[0078] [Table 2]

[0079] As shown in Table 2, the recycled treatment solution prepared in Example 2 showed good resin mask peelability. [Industrial applicability]

[0080] This disclosure provides a substrate processing method with excellent resin mask removal (peelability). Furthermore, by using the substrate processing method of this disclosure, it is possible to improve the performance and reliability of manufactured electronic components and increase the productivity of semiconductor devices. [Explanation of Symbols]

[0081] 1. Resin mask layer (dry film resist) 2. Metal layer (metal plating layer)

Claims

1. A method for processing a substrate, comprising the following steps 1, 2, and 3. Step 1: A process of treating a substrate having a resin mask using a treatment solution obtained using an aqueous solution (Solution A) containing an aliphatic quaternary ammonium hydroxide and an alkanolamine. Step 2: A step to determine the concentration of carbonate ions (carbonate concentration) in the processing solution (Solution C) used in Step 1. Step 3: A step to calculate the amount of alkanolamine contained in Solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in Solution C, based on the carbon dioxide concentration in Solution C determined in Step 2.

2. Furthermore, the treatment method according to claim 1, further comprising step 4: mixing solution A with solution C based on the amount of alkanolamine calculated in step 3 to prepare a reuse treatment solution.

3. The processing method according to claim 2, wherein step 4 includes mixing an aqueous solution (solution B) containing an organic solvent and an alkanolamine with solution C based on the amount of alkanolamine calculated in step 3.

4. A method for processing a substrate, comprising the following steps 1, 2, and 3. Step 1: A process of processing a substrate having a resin mask using a treatment solution obtained by mixing an aqueous solution containing an aliphatic quaternary ammonium hydroxide and an alkanolamine (Solution A) with an aqueous solution containing an organic solvent and an alkanolamine (Solution B). Step 2: A step to determine the concentration of carbonate ions (carbonate concentration) in the processing solution (Solution C) used in Step 1. Step 3: A step to calculate the amount of alkanolamine contained in Solution A, which contains the same amount of aliphatic quaternary ammonium hydroxide as the aliphatic quaternary ammonium hydroxide consumed in neutralizing the carbon dioxide in Solution C, based on the carbon dioxide concentration in Solution C determined in Step 2.

5. Furthermore, the treatment method according to claim 4, further comprising step 4: mixing solution A with solution C based on the amount of alkanolamine calculated in step 3 to prepare a reuse treatment solution.

6. The processing method according to claim 5, wherein step 4 includes mixing solution B with solution C based on the amount of alkanolamine calculated in step 3.

7. The substrate processing method according to claim 1 or 4, further comprising step 3, which involves calculating the amount of the alkanolamine using the following formula (I). Amount of alkanolamine (mass%) = [Carbon dioxide concentration in solution C (mol / L) × C × Molar mass of aliphatic quaternary ammonium hydroxide (g / mol)] ÷ Amount of aliphatic quaternary ammonium hydroxide in solution A (mass%) × Amount of alkanolamine in solution A (mass%) (I) However, in formula (I) above, the coefficient C is a coefficient determined based on the degree of neutralization, the number of neutralization additions, and the unit conversion coefficient, and is a value in the range of 0.01 to 1.

8. The method for processing a substrate according to claim 1 or 4, wherein the molar ratio of aliphatic quaternary ammonium hydroxide to carbonate ions in the aforementioned solution C is 0.01 or more and 100 or less.

9. A method for peeling off a resin mask, comprising peeling off the resin mask from a substrate having a resin mask using the substrate processing method described in claim 1 or 4.

10. A method for manufacturing an electronic component substrate, comprising the substrate processing method described in claim 1 or 4.

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