Cleaning method

Abstract

To provide a cleaning method which is excellent in resin mask removal property and stability.SOLUTION: A cleaning method includes a step of peeling a resin mask from an object to be cleaned attached with a resin mask, using a cleaning agent composition. The cleaning agent composition contains alkanolamine (component A), quaternary ammonium hydroxide (component B), glycol ether (component C) and water (component D). A content of the component A in the cleaning agent composition is 3 mass% or more and 18 mass% or less, a content of the component B is 1 mass% or more and 15 mass% or less, a content of the component C is 2 mass% or more and 10 mass% or less, a content of the component D is 60 mass% or more and 90.5 mass% or less, a mass ratio A / C is 0.9 or more and 1.9 or less, and a mass ratio B / C is 0.35 or more and 2.0 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to a cleaning method and a method for manufacturing electronic components using the same. [Background technology]

[0002] In recent years, personal computers and various electronic devices have become more energy efficient, faster, and smaller, and the wiring on package substrates mounted on these devices is becoming finer year by year. Until now, the metal mask method has been mainly used to form such fine wiring and connection terminals such as pillars and bumps, but due to its low versatility and the difficulty of responding to the miniaturization of wiring, etc., other new methods are being used.

[0003] One of the new methods is to use a dry film resist as a thick resin mask instead of a metal mask. This resin mask is finally peeled off and removed, and an alkaline stripping cleaner is used for this purpose.

[0004] For example, Patent Document 1 proposes a method of stripping a water-soluble resist with a strong alkaline aqueous solution (stripping solution) of sodium hydroxide, potassium hydroxide, etc. Paragraph 0013 of the same document lists sulfites and the like as additives to the strong alkaline aqueous solution. Patent Document 2 proposes a cleaning composition for stripping resin masks, which contains an alkaline agent (component A), an organic solvent (component B), a chelating agent (component C) and water, in which component B is at least one solvent selected from glycol ethers and aromatic ketones, and component C is a compound having two or more acid groups of at least one type selected from carboxy groups and phosphonic acid groups, and the content of component B at the time of use is from 1% by mass to 12% by mass, and the content of component D at the time of use is from 65% by mass to 95% by mass. Patent Document 3 proposes a cleaning composition for removing resin masks, which contains a specific amino alcohol (component A), a specific tetraalkylammonium hydroxide (component B), a carboxylic acid having from 1 to 5 carbon atoms or a salt thereof (component C), a specific glycol ether (component D), a specific imidazole compound (component E), and water (component F). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 6-250401 [Patent Document 2] JP 2021-006904 A [Patent Document 3] JP 2017-116871 A Summary of the Invention [Problem to be solved by the invention]

[0006] When forming fine wiring on printed circuit boards and the like, a cleaning composition is required to have high cleaning properties in order to reduce not only the residue of a resin mask but also the residue of auxiliary agents contained in solder, plating solution, and the like used in forming the fine wiring and bumps. However, as wiring becomes finer, it becomes more difficult to remove the resin mask from the fine gaps, and therefore cleaning compositions are required to have high resin mask removing properties. In recent years, substrates having various patterns have been proposed. For example, as shown in Fig. 1, in the case of a substrate having a metal layer 2 (e.g., a copper plating layer) formed on the substrate surface and a resin mask layer 1 present in the form of perforations on the metal layer 2 (i.e., a substrate having a structure in which the periphery (side surface) of the resin mask layer is surrounded by a metal layer), a conventional detergent composition has difficulty penetrating into the interface between the resin mask and the metal layer, making it difficult to peel off the resin mask. On the other hand, the stability of the cleaning chemicals themselves is required for stable production. Problems include the occurrence of sedimentation or unevenness, which can make it difficult to clean substrates with consistent quality. Until now, cleaning chemicals with high resin removal capabilities have been investigated, but such chemicals often lack stability (prevention of component separation).

[0007] Therefore, the present disclosure provides a cleaning method that is excellent in resin mask removability and stability. [Means for solving the problem]

[0008] In one aspect, the present disclosure relates to a cleaning method including a step of peeling off a resin mask from an object to be cleaned to which the resin mask is attached by using a cleaning composition, the cleaning composition containing an alkanolamine (component A), a quaternary ammonium hydroxide (component B), a glycol ether (component C) and water (component D), the content of component A in the cleaning composition is 3% by mass or more and 18% by mass or less, the content of component B in the cleaning composition is 1% by mass or more and 15% by mass or less, the content of component C in the cleaning composition is 2% by mass or more and 10% by mass or less, the content of component D in the cleaning composition is 60% by mass or more and 90.5% by mass or less, a mass ratio A / C of component A to component C in the cleaning composition is 0.9 or more and 1.9 or less, and a mass ratio B / C of component B to component C in the cleaning composition is 0.35 or more and 2.0 or less. Effect of the Invention

[0009] According to the present disclosure, a cleaning method excellent in resin mask removability and stability can be provided. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing an example of the appearance of a substrate surface of a substrate to be cleaned. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present disclosure is based on the discovery that by using a cleaning composition containing an alkanolamine (component A), a quaternary ammonium hydroxide (component B), and a glycol ether (component C) in a specific mass ratio, a resin mask can be efficiently removed from a substrate surface and a state with excellent stability (suppression of separation of components) can be maintained.

[0012] In one aspect, the present disclosure relates to a cleaning method (hereinafter also referred to as "the cleaning method of the present disclosure") comprising a step of peeling off a resin mask from an object to be cleaned to which the resin mask is attached, by using a cleaning composition (hereinafter also referred to as "the cleaning composition of the present disclosure"), the cleaning composition containing an alkanolamine (component A), a quaternary ammonium hydroxide (component B), a glycol ether (component C) and water (component D), the content of component A in the cleaning composition is 3% by mass or more and 18% by mass or less, the content of component B in the cleaning composition is 1% by mass or more and 15% by mass or less, the content of component C in the cleaning composition is 2% by mass or more and 10% by mass or less, the content of component D in the cleaning composition is 60% by mass or more and 90.5% by mass or less, a mass ratio A / C of component A to component C in the cleaning composition is 0.9 or more and 1.9 or less, and a mass ratio B / C of component B to component C in the cleaning composition is 0.35 or more and 2.0 or less.

[0013] According to the present disclosure, a cleaning method excellent in resin mask removability and stability can be provided. By using the cleaning method of the present disclosure for cleaning electronic components such as electronic circuit boards to which a resin mask is attached, high-quality electronic components can be obtained with high production efficiency and high yield.

[0014] Although the details of the mechanism of action by which the effects of the present disclosure are expressed are unclear, it is presumed as follows. In the present disclosure, it is believed that the alkanolamine (component A) and the quaternary ammonium hydroxide (component B) penetrate into the resin mask and promote dissociation of the alkali-soluble resin contained in the resin mask, and further promote swelling of the resin mask by causing repulsion of the charges generated by the dissociation. On the other hand, when the substrate to be cleaned has a structure with a high interface ratio (=interface line length between the resin mask and the metal layer / area of ​​the resin mask) in which the periphery of the resin mask 1 present in the form of perforations is surrounded by the metal layer 2 as shown in FIG. 1, it is considered that peeling does not proceed easily only by swelling to the resin mask. However, in the present disclosure, by using alkanolamine (component A), quaternary ammonium hydroxide (component B) and glycol ether (component C) in combination at a specific ratio, it is considered that the cleaning composition easily penetrates into the interface between the resin mask and the metal layer, and peeling proceeds as if the resin mask is rolling up. Furthermore, it is considered that the cleaning composition easily penetrates into the interface between the resin mask and the metal layer, and therefore high peelability and stability of the components (suppression of separation of the components) can be maintained even if deterioration or reduction in the component concentration occurs during actual use. However, the present disclosure need not be construed as being limited to this mechanism.

[0015] In the present disclosure, a resin mask is a mask for protecting a material surface from treatments such as etching, plating, and heating, that is, a mask that functions as a protective film. In one or more embodiments, the resin mask may be a resist layer after exposure and development steps, a resist layer that has been subjected to at least one of exposure and development (hereinafter also referred to as "exposed and / or developed"), or a hardened resist layer. In one or more embodiments, the resin mask is formed using a resist whose physical properties, such as solubility in a developer, change due to light, electron beams, or the like. Resists are broadly divided into negative and positive types based on the reaction method with light or electron beams. A negative resist has a property that its solubility in a developer decreases when exposed to light, and the exposed portion of a layer containing a negative resist (hereinafter also referred to as a "negative resist layer") is used as a resin mask after exposure and development processing. A positive resist has a property that its solubility in a developer increases when exposed to light, and the exposed portion of a layer containing a positive resist (hereinafter also referred to as a "positive resist layer") is removed after exposure and development processing, and the unexposed portion is used as a resin mask. By using a resin mask having such properties, fine connections of a circuit board, such as metal wiring, metal pillars, and solder bumps, can be formed. In one or more embodiments, the resin material for forming the resin mask may be a film-like photosensitive resin, a resist film, or a photoresist. A general-purpose resist film may be used.

[0016] [Peeling process] The cleaning method of the present disclosure includes a step of peeling off the resin mask from the object to be cleaned to which the resin mask is attached, using the cleaning composition of the present disclosure (hereinafter, also simply referred to as a "peeling step"). In one or more embodiments, the peeling step includes contacting the object to be cleaned to which the resin mask is attached, with the cleaning composition of the present disclosure. The cleaning method of the present disclosure is excellent in stability (suppression of separation of components), and can efficiently remove the resin mask.

[0017] Examples of the method of peeling off a resin mask from an object to be cleaned using the cleaning composition of the present disclosure, or the method of contacting the object to be cleaned with the cleaning composition of the present disclosure include a method of contacting the object by immersing the object in a cleaning bath containing the cleaning composition, a method of contacting the object by spraying the cleaning composition in a spray form (shower method), and an ultrasonic cleaning method of irradiating the object with ultrasonic waves during immersion. The cleaning composition of the present disclosure can be used for cleaning as is without dilution. Examples of the object to be cleaned include the above-mentioned objects to be cleaned. The immersion time can be, for example, 1 minute or more and 10 minutes or less, and further 3 minutes or more and 6 minutes or less. The spray time can be, for example, 1 minute or more and 10 minutes or less, and further 3 minutes or more and 6 minutes or less.

[0018] In one or more embodiments, the cleaning method of the present disclosure may include a step of contacting the object to be cleaned with the cleaning composition, rinsing with water, and drying. Examples of the rinsing method include rinsing with running water. Examples of the drying method include air blow drying. In one or more embodiments, the cleaning method of the present disclosure may include a step of rinsing the object to be cleaned with water after contacting the object with the cleaning composition.

[0019] In the cleaning method of the present disclosure, it is preferable to irradiate ultrasonic waves when the cleaning composition of the present disclosure comes into contact with the object to be cleaned, and it is more preferable that the ultrasonic waves have a relatively high frequency, from the viewpoint of making it easier for the cleaning power of the cleaning composition of the present disclosure to be exerted. From the same viewpoint, the ultrasonic irradiation conditions are, for example, preferably 26 to 72 kHz and 80 to 1500 W, and more preferably 36 to 72 kHz and 80 to 1500 W.

[0020] In the cleaning method of the present disclosure, the temperature of the cleaning composition is preferably 40° C. or higher, and more preferably 50° C. or higher, from the viewpoint of allowing the cleaning power of the cleaning composition of the present disclosure to be easily exerted, and is preferably 70° C. or lower, and more preferably 60° C. or lower, from the viewpoint of reducing the effect on the organic resin-containing substrate.

[0021] [Item to be cleaned] In one or more embodiments, the cleaning composition of the present disclosure can be used for cleaning an object to be cleaned having a resin mask attached thereto. In one or more embodiments, the object to be cleaned with the resin mask attached thereto may be a substrate having a metal layer and a resin mask on its surface. The substrate may be, for example, a glass epoxy multilayer substrate. In one or more embodiments, the metal layer is a copper plating layer. The copper plating layer can be formed by, for example, an electroless copper plating method. The thickness of the metal layer can be, for example, 3 μm or more and 30 μm or less.

[0022] In one or more embodiments, the resin mask may be a resin mask (resin mask layer) present in the form of perforations in the metal layer (see FIG. 1). In one or more embodiments, the sides of the resin mask are surrounded by the metal layer. In one or more embodiments, the shape of the resin mask layer may be a polygonal (square, hexagonal, octagonal, etc.) columnar, cylindrical, approximately cylindrical, etc. The diameter of the resin mask layer (diameter of the circumscribing circle in the case of a polygonal shape) may be, for example, 20 μm or more and 200 μm or less. The thickness of the resin mask layer may be, for example, 5 μm or more and 50 μm or less. The interface ratio of the resin mask present in the form of perforations (=interface line length between the resin mask and the metal layer / area of ​​the resin mask) can be 0.01 to 0.5, or 0.02 to 0.2. Here, the interface line length between the resin mask and the metal layer is, for example, the circumferential length when the resin mask is a circle when viewed from above. A new problem has been found in that the resin mask of the object to be cleaned having such a resin mask structure has poor removability when used with a conventional stripper. In one or more embodiments, the cleaning agent composition according to the present disclosure can suitably remove a resin mask having such a structure. In one or more embodiments, the object to be cleaned in the present disclosure may be an object to be cleaned having at least one resin mask attached in the form of perforations in a metal layer, as described above.

[0023] In one or more other embodiments, the object to be cleaned with the resin mask attached thereto may be, for example, an electronic component having a metal layer and a resin mask on its surface, or an intermediate product thereof. The electronic component may be, for example, at least one component selected from a printed circuit board, a wafer, and a metal plate such as a copper plate or an aluminum plate. The intermediate product is an intermediate product in the manufacturing process of the electronic component, and includes an intermediate product after the resin mask treatment. Specific examples of objects to be cleaned with a resin mask attached include electronic components in which wiring, connection terminals, etc. are formed on the surface of a substrate by at least one of soldering and plating (copper plating, aluminum plating, nickel plating, tin plating, etc.) using a resin mask. In the present disclosure, soldering refers to providing solder in the resin mask-free portion of a substrate and forming a solder bump by heating. In the present disclosure, plating refers to performing at least one plating treatment selected from copper plating, aluminum plating, nickel plating, and tin plating on the resin mask-free portion of a substrate. The resin mask-free portion refers to a portion in a resist pattern (a resin mask having a pattern shape) formed by subjecting a resin mask laminated to a substrate to a developing treatment, from which the resin mask has been removed by the developing treatment. Thus, in one aspect, the present disclosure relates to the use of the cleaning composition of the present disclosure as a cleaning agent in the manufacture of electronic components.

[0024] In one or more embodiments, the cleaning method of the present disclosure can be suitably used for cleaning an object to which a resin mask or a resin mask that has been further plated and / or heated is attached, from the viewpoint of cleaning effect. The resin mask may be, for example, a negative resin mask or a positive resin mask, and a negative resin mask is preferable from the viewpoint of the ease with which the effects of the present disclosure are exerted. An example of a negative resin mask is a negative dry film resist that has been exposed and / or developed. In the present disclosure, a negative resin mask is formed using a negative resist, and an example of the negative resin mask is a negative resist layer that has been exposed and / or developed. In the present disclosure, a positive resin mask is formed using a positive resist, and an example of the positive resin mask is a positive resist layer that has been exposed and / or developed.

[0025] [Cleaning agent composition] In one or more embodiments, the cleaning composition of the present disclosure is a cleaning composition containing the following components A, B, C, and D. By using the cleaning composition of the present disclosure for cleaning an object to be cleaned having a resin mask attached thereto, the resin mask can be efficiently removed. Furthermore, by using the cleaning composition of the present disclosure for cleaning electronic components such as electronic circuit boards having a resin mask, high-quality electronic components can be obtained in high yield. In one or more embodiments, the cleaning composition of the present disclosure can be used for cleaning an object to which a resin mask is attached. In one or more embodiments, the cleaning composition of the present disclosure can be used for removing the resin mask from an object to which the resin mask is attached. That is, in one aspect, the present disclosure relates to use of the cleaning composition of the present disclosure for removing the resin mask from an object to which the resin mask is attached.

[0026] (Component A: Alkanolamine) Examples of alkanolamines (amino alcohols) (hereinafter also referred to as "Component A") contained in the cleaning composition of the present disclosure include compounds represented by the following formula (I). Component A may be one type or a combination of two or more types. [ka]

[0027] In the above formula (I), R 1 represents a hydrogen atom, a methyl group, an ethyl group, or an aminoethyl group; R 2 represents a hydrogen atom, a hydroxyethyl group, a hydroxypropyl group, a methyl group, or an ethyl group; R 3 represents a hydroxyethyl group or a hydroxypropyl group.

[0028] Examples of component A include 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 removability of the resin mask.

[0029] The content of component A when using the cleaning composition of the present disclosure is 3% by mass or more, preferably 5% by mass or more, more preferably 8% by mass or more, from the viewpoint of improving resin mask removability, and from the same viewpoint, is 18% by mass or less, preferably 12% by mass or less, more preferably 10% by mass or less. From the same viewpoint, the content of component A when using the cleaning composition of the present disclosure is 3% by mass or more and 18% by mass or less, preferably 5% by mass or more and 12% by mass or less, more preferably 8% by mass or more and 10% by mass or less. When component A is a combination of two or more types, the content of component A refers to the total content thereof.

[0030] In the present disclosure, "the content of each component at the time of use of the detergent composition" refers to the content of each component at the time of cleaning, i.e., at the time when the detergent composition starts to be used for cleaning. In one or more embodiments, the content of each component in the cleaning composition of the present disclosure can be considered as the blending amount of each component in the cleaning composition of the present disclosure.

[0031] (Component B: Quaternary ammonium hydroxide) The quaternary ammonium hydroxide (hereinafter also referred to as "Component B") contained in the cleaning composition of the present disclosure may be, for example, a quaternary ammonium hydroxide represented by the following formula (II). Component B may be one type or a combination of two or more types. [ka]

[0032] In the above formula (II), R 4 , R 5 , R 6 and R 7 are each 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.

[0033] The quaternary ammonium hydroxide represented by formula (II) is a salt consisting of a quaternary ammonium cation and a hydroxide, and examples thereof include 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 removability of the resin mask.

[0034] The content of component B when using the cleaning composition of the present disclosure is 1% by mass or more, preferably 2% by mass or more, more preferably 3% by mass or more, from the viewpoint of improving resin mask removability, and from the same viewpoint, is 15% by mass or less, preferably 10% by mass or less, more preferably 5% by mass or less. From the same viewpoint, the content of component B when using the cleaning composition of the present disclosure is 1% by mass or more and 15% by mass or less, preferably 2% by mass or more and 10% by mass or less, more preferably 3% by mass or more and 5% by mass or less. When component B is a combination of two or more kinds, the content of component B refers to the total content thereof.

[0035] The total content of component A and component B when using the cleaning composition of the present disclosure is preferably 6% by mass or more, more preferably 8% by mass or more, even more preferably 10% by mass or more, and even more preferably 12% by mass or more, from the viewpoint of improving the removability of the resin mask, and from the same viewpoint, it is preferably 20% by mass or less, more preferably 18% by mass or less, even more preferably 16% by mass or less, and even more preferably 14% by mass or less. From the same viewpoint, the total content of component A and component B when using the cleaning composition of the present disclosure is preferably 6% by mass or more and 20% by mass or less, more preferably 8% by mass or more and 18% by mass or less, even more preferably 10% by mass or more and 16% by mass or less, and even more preferably 12% by mass or more and 14% by mass or less.

[0036] (Component C: Glycol ether) The glycol ether (hereinafter also referred to as "component C") contained in the cleaning composition of the present disclosure may be a compound having a structure in which 1 to 3 moles of ethylene glycol are added to an alcohol having 1 to 8 carbon atoms from the viewpoint of improving resin mask removability. Examples of the glycol ether include at least one selected from diethylene glycol monobutyl ether (BDG), ethylene glycol monobenzyl ether, diethylene glycol monohexyl ether, ethylene glycol monophenyl ether, and diethylene glycol diethyl ether. Among these, diethylene glycol monobutyl ether (BDG) is preferred from the viewpoint of improving resin mask removability. Component C may be one type or a combination of two or more types.

[0037] The content of component C when using the cleaning composition of the present disclosure is 2% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more, from the viewpoint of improving resin mask removability, and from the same viewpoint, is 10% by mass or less, preferably 8% by mass or less, more preferably 6% by mass or less. From the same viewpoint, the content of component C when using the cleaning composition of the present disclosure is 2% by mass or more and 10% by mass or less, preferably 3% by mass or more and 8% by mass or less, more preferably 5% by mass or more and 6% by mass or less. When component C is a combination of two or more kinds, the content of component C refers to the total content thereof.

[0038] The mass ratio A / C of component A to component C during use of the cleaning composition of the present disclosure is 0.9 or more, preferably 1.0 or more, more preferably 1.1 or more, and even more preferably 1.2 or more, from the viewpoints of stability (suppression of separation of components), improvement of resin mask removability, and suppression of damage to the substrate resin, and from the same viewpoint, is 1.9 or less, preferably 1.8 or less, and more preferably 1.7 or less. From the same viewpoint, the mass ratio A / C in the cleaning composition of the present disclosure, in one or more embodiments, is 0.9 or more and 1.9 or less, preferably 1.0 or more and 1.8 or less, more preferably 1.1 or more and 1.7 or less, and even more preferably 1.2 or more and 1.7 or less.

[0039] The mass ratio B / C of component B to component C during use of the cleaning composition of the present disclosure is 0.35 or more, preferably 0.4 or more, and more preferably 0.45 or more, from the viewpoints of stability (suppression of separation of components), improvement of resin mask removability, and suppression of damage to the substrate resin, and from the same viewpoint, is 2.0 or less, preferably 1.5 or less, more preferably 1.0 or less, and even more preferably 0.7 or less. From the same viewpoint, the mass ratio B / C in the cleaning composition of the present disclosure, in one or more embodiments, is 0.35 or more and 2.0 or less, preferably 0.4 or more and 1.5 or less, more preferably 0.45 or more and 1.0 or less, and even more preferably 0.45 or more and 0.7 or less.

[0040] (Component D: water) In one or a plurality of embodiments, examples of water contained in the cleaning agent composition of the present disclosure (hereinafter also referred to as "component D") include ion-exchanged water, RO water, distilled water, pure water, and ultrapure water.

[0041] The content of component D in the cleaning composition of the present disclosure may be the remainder excluding components A, B, C, and optional components described later. Specifically, the content of component D when using the cleaning composition of the present disclosure is 60% by mass or more, preferably 70% by mass or more, and more preferably 80% by mass or more, from the viewpoints of improving resin mask removability, reducing wastewater treatment load, and suppressing damage to the substrate resin, and is 90.5% by mass or less, preferably 88% by mass or less, and more preferably 85% by mass or less, from the viewpoint of improving resin mask removability. From the same viewpoint, the content of component D when using the cleaning composition of the present disclosure is 60% by mass or more and 90.5% by mass or less, preferably 70% by mass or more and 88% by mass or less, and more preferably 80% by mass or more and 85% by mass or less.

[0042] (Other Ingredients) The cleaning composition of the present disclosure may further contain other components as necessary in addition to the above-described Components A to D. Examples of other components include components that can be used in ordinary cleaning agents, such as alkaline agents other than Components A and B, amines other than Component A, organic solvents other than Component C, surfactants, chelating agents, thickeners, dispersants, rust inhibitors, polymeric compounds, solubilizers, antioxidants, preservatives, defoamers, and antibacterial agents.

[0043] In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of triazoles. The content of triazoles in the cleaning composition of the present disclosure during use is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., no triazoles are contained). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of a water-insoluble solvent. The content of the water-insoluble solvent in the cleaning composition of the present disclosure during use is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., no water-insoluble solvent is contained). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of an organophosphorus compound or a salt thereof. The content of the organophosphorus compound or a salt thereof during use of the cleaning composition of the present disclosure is preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., no organic phosphorus compound or salt thereof). In one or a plurality of embodiments, the cleaning composition of the present disclosure may be substantially free of a carboxylic acid or a salt thereof having from 1 to 5 carbon atoms. The content of the carboxylic acid or a salt thereof having from 1 to 5 carbon atoms during use of the cleaning composition of the present disclosure is preferably less than 0.05% by mass, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., free of any carboxylic acid or salt thereof). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of imidazole-based compounds. The content of the imidazole-based compounds during use of the cleaning composition of the present disclosure is preferably less than 0.05% by mass, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., free of imidazole-based compounds). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of a chelating agent. The content of the chelating agent in the cleaning composition of the present disclosure during use is preferably less than 0.5% by mass, more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., no chelating agent is contained). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of thioglycolic acid. The content of thioglycolic acid in the cleaning composition of the present disclosure during use is preferably less than 0.4% by mass, more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., free of thioglycolic acid). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of N-oxide compounds. The content of N-oxide compounds during use of the cleaning composition of the present disclosure is preferably less than 0.05% by mass, more preferably 0.01% by mass or less, and even more preferably 0% by mass (i.e., no N-oxide compounds). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of urea. The content of urea in the cleaning composition of the present disclosure during use is preferably less than 0.5% by mass, more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., free of urea). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of aromatic alcohol. The content of aromatic alcohol in the cleaning composition of the present disclosure during use is preferably less than 5% by mass, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and even more preferably 0% by mass (i.e., no aromatic alcohol). In one or more embodiments, the cleaning composition of the present disclosure may be substantially free of a sulfite reducing agent. The content of the sulfite reducing agent during use of the cleaning composition of the present disclosure is preferably less than 0.01% by mass, more preferably 0% by mass (i.e., no sulfite reducing agent is contained).

[0044] (Method of producing the cleaning composition) In one or more embodiments, the cleaning composition of the present disclosure can be produced by blending the components A to D and, if necessary, the optional components (other components) described above, by a known method. For example, the cleaning composition of the present disclosure can be produced by blending at least the components A to D. Thus, the present disclosure relates to a method for producing a cleaning composition, which includes a step of blending at least the components A to D. In the present disclosure, "blending" includes mixing the components A to D and, if necessary, the optional components described above simultaneously or in any order. In the method for producing a cleaning composition of the present disclosure, the preferred blending amount of each component can be the same as the preferred content of each component of the cleaning composition of the present disclosure described above.

[0045] The cleaning composition of the present disclosure may be prepared as a concentrate in which the amount of water (component D) is reduced to the extent that separation, precipitation, etc. do not occur and storage stability is not impaired. The concentrate of the cleaning composition is preferably a concentrate having a dilution ratio of 3 times or more from the viewpoint of transportation and storage, and is preferably a concentrate having a dilution ratio of 30 times or less from the viewpoint of storage stability. The concentrate of the cleaning composition can be used by diluting with water (component D) so that the components A to D and optional components have the above-mentioned contents (i.e., contents at the time of cleaning) at the time of use. Furthermore, the concentrate of the cleaning composition can also be used by adding each component separately at the time of use. In the present disclosure, "at the time of use" or "at the time of cleaning" of the concentrated cleaning composition refers to a state in which the concentrate of the cleaning composition is diluted.

[0046] [Electronic component manufacturing method] In one aspect, the present disclosure relates to a method for producing electronic components, the method including a step of peeling off a resin mask from an object to be cleaned to which the resin mask is attached, using the cleaning method of the present disclosure. The object to be cleaned can be any of the above-mentioned objects to be cleaned. In another aspect, the present disclosure relates to a method for producing electronic components, comprising a step of cleaning an electronic circuit board having a resin mask with the cleaning composition of the present disclosure (hereinafter also referred to as a "cleaning step"). The cleaning method in the cleaning step may be the same as the cleaning method of the present disclosure described above. According to the manufacturing method of electronic components of the present disclosure, the resin mask attached to the electronic components can be effectively removed, which enables the manufacturing of highly reliable electronic components. Furthermore, by carrying out the cleaning method of the present disclosure, the resin mask attached to the electronic components can be easily peeled off, which shortens the cleaning time and improves the manufacturing efficiency of electronic components.

[0047] [kit] In one aspect, the present disclosure relates to a kit for use in either the cleaning method of the present disclosure or the method for producing electronic components of the present disclosure (hereinafter, also referred to as the "kit of the present disclosure"). In one or more embodiments, the kit of the present disclosure is a kit for producing the cleaning composition of the present disclosure. According to the kit of the present disclosure, a cleaning composition having excellent resin mask removability and stability (suppression of separation of components) can be obtained.

[0048] One embodiment of the kit of the present disclosure includes a kit (three-liquid type cleaning agent composition) that includes a solution (first liquid) containing component A, a solution (second liquid) containing component B, and a solution (third liquid) containing component C in a mutually unmixed state, and at least one selected from the first liquid, the second liquid, and the third liquid further contains a part or all of component D (water), and the first liquid, the second liquid, and the third liquid are mixed at the time of use. After the first liquid, the second liquid, and the third liquid are mixed, they may be diluted with component D (water) as necessary. Each of the first liquid, the second liquid, and the third liquid may contain the above-mentioned optional components as necessary. Other embodiments of the kit of the present disclosure include a kit (two-liquid type cleaning agent composition) that includes a solution (first liquid) containing component A and component B and a solution (second liquid) containing component C in a mutually unmixed state, at least one of the first liquid and the second liquid further contains a part or all of component D (water), and the first liquid and the second liquid are mixed at the time of use. After the first liquid and the second liquid are mixed, they may be diluted with component D (water) as necessary. Each of the first liquid and the second liquid may contain the above-mentioned optional components as necessary. EXAMPLES

[0049] The present disclosure will be specifically described below with reference to examples, but the present disclosure is not limited to these examples in any way.

[0050] 1. Preparation of cleaning compositions of Examples 1 to 5 and Comparative Examples 1 to 7 The cleaning compositions of Examples 1 to 5 and Comparative Examples 1 to 7 were prepared by mixing the components shown in Table 1 in the amounts (mass %, active content) shown in Table 1 and stirring to mix.

[0051] The cleaning compositions of Examples 1 to 5 and Comparative Examples 1 to 7 were prepared using the following materials. (Component A) MEA: Monoethanolamine [manufactured by Nippon Shokubai Co., Ltd.] (Component B) TMAH: Tetramethylammonium hydroxide [Resonac Corporation, 25% aqueous solution] (Component C) BDG: Butyl diglycol [manufactured by Nippon Nyukazai Co., Ltd.] (Component D) Water [Pure water of 1μS / cm or less produced using the Organo Corporation pure water system G-10DSTSET]

[0052] 2. Evaluation of the cleaning compositions of Examples 1 to 5 and Comparative Examples 1 to 7 The prepared cleaning compositions of Examples 1 to 5 and Comparative Examples 1 to 7 were evaluated as follows.

[0053] [Test piece] The test piece was 120 mm x 120 mm in size, and as shown in Figure 1, had a 15 μm-thick metal layer 2 formed by copper plating on the surface of a glass epoxy multilayer substrate, and a 25 μm-thick resin mask layer 1 made of negative dry film resist in a circular area with a diameter of 75 μm present in the form of perforations in the metal layer 2, with 15 μm of the 25 μm-thick resin mask being buried in the metal layer.

[0054] [Evaluation of stability (prevention of component separation) and resin mask removability (peelability)] 3 kg of each cleaning composition was added to a 5 L stainless steel beaker, and then Component D (water) was added to dilute the composition so that the amounts of Components A, B, and C were 0.8% less than those immediately after preparation. Carbon dioxide was then bubbled in while allowing 0.9 mol / L of carbon dioxide to accumulate in the cleaning composition. The appearance was then visually observed, and the stability (suppression of component separation) was evaluated according to the following criteria. Next, this was heated to 60°C, and the test piece was sprayed for 90 seconds (pressure: 0.2 MPa, spray distance: 8 cm) while circulating with a box-type spray washer equipped with a one-fluid nozzle (full cone type) J020 (manufactured by Ikeuchi Co., Ltd.). Then, water was poured for 30 seconds to rinse, and then dried by nitrogen blowing. Using an optical microscope "Digital Microscope VHX-6000" (manufactured by Keyence Co., Ltd.), the presence or absence of resin mask residue remaining on the test piece after the above-mentioned spray treatment was visually confirmed at 100 times magnification. Based on the appearance of the cleaning composition when carbon dioxide was accumulated and the presence or absence of resin mask residue after the spray treatment, the resin mask removability (peelability) was evaluated according to the following criteria. The results are shown in Table 1. <Stability (prevention of component separation) criteria> A: At 60℃, it becomes slightly cloudy but does not separate. B: Cloudy at 60℃ but does not separate C: At 60℃, it becomes very cloudy but does not separate. D: At 60℃, it becomes extremely cloudy and separates, making it difficult to handle. <Criteria for determining resin mask removability (peelability)> A: No resin mask residue B: Resin mask residue of 3% or less C: Resin mask residue is greater than 3% and less than 10% D: Resin mask residue exceeds 10%

[0055] [Table 1]

[0056] As shown in Table 1, the cleaning compositions of Examples 1 to 5, in which the mass ratio A / C was in the range of 0.9 to 1.9 and the mass ratio B / C was in the range of 0.35 to 2.0, were found to be superior in resin mask removability and stability compared to Comparative Examples 1 to 7. Furthermore, even in the cases where either the mass ratio A / C or the mass ratio B / C fell within the specified range as in Comparative Examples 5 to 7, it was found that the resin mask removability and stability could not be satisfied. [Industrial Applicability]

[0057] According to the present disclosure, a cleaning method excellent in resin mask removability and stability can be provided. Furthermore, by using the cleaning method of the present disclosure, it is possible to improve the performance and reliability of manufactured electronic components, and to improve the productivity of semiconductor devices. [Explanation of symbols]

[0058] 1 Resin mask layer (dry film resist) 2 Metal layer (metal plating layer)

Claims

1. The process includes using a cleaning agent composition to remove the resin mask from the object to be cleaned, to which the resin mask is attached. The aforementioned detergent composition contains an alkanolamine (component A), a quaternary ammonium hydroxide (component B), a glycol ether (component C), and water (component D). The content of component A in the aforementioned detergent composition is 3% by mass or more and 18% by mass or less. The content of component B in the aforementioned detergent composition is 1% by mass or more and 15% by mass or less. The content of component C in the aforementioned detergent composition is 2% by mass or more and 10% by mass or less. The content of component D in the aforementioned detergent composition is 60% by mass or more and 90.5% by mass or less. The mass ratio A / C of component A to component C in the aforementioned detergent composition is 0.9 or more and 1.9 or less. A cleaning method wherein the mass ratio B / C of component B to component C in the cleaning agent composition is 0.35 or more and 2.0 or less.

2. The cleaning method according to claim 1, wherein component A is monoethanolamine.

3. The cleaning method according to claim 1, wherein component B is tetramethylammonium hydroxide.

4. The cleaning method according to claim 1, wherein component C is diethylene glycol monobutyl ether.

5. The cleaning method according to claim 1, wherein the mass ratio A / C of component A to component C in the cleaning agent composition is 1.2 or more and 1.7 or less.

6. The cleaning method according to claim 1, wherein the mass ratio B / C of component B to component C in the cleaning agent composition is 0.45 or more and 0.7 or less.

7. The cleaning method according to claim 1, wherein the cleaning agent composition does not contain triazoles.

8. The cleaning method according to claim 1, wherein the cleaning agent composition does not contain a water-insoluble solvent.

9. The cleaning method according to claim 1, wherein the cleaning agent composition does not contain an organophosphorus compound or a salt thereof.

10. The cleaning method according to any one of claims 1 to 9, wherein the object to be cleaned to which the resin mask is attached is a substrate having a metal layer and a resin mask on its surface.

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