Stripping composition

Abstract

To provide a release agent composition with superior resin mask removability (releasability) in one embodiment.SOLUTION: According to one embodiment, a release agent composition contains an alkali agent, an organic solvent other than the alkali agent, water, and an O / W emulsion.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a stripper composition, a method for stripping a resin mask, and a method for manufacturing an electronic component. [Background technology]

[0002] In recent years, personal computers and various electronic devices have become increasingly power-efficient, faster, and more compact, and the wiring on the package substrates and other components they are equipped with has been getting finer every year. Until now, metal masking has been the primary method used to form such fine wiring and connection terminals such as pillars and bumps, but due to its limited versatility and the difficulty of adapting to the miniaturization of wiring, new methods are being adopted.

[0003] One new method is to use a dry film resist as a thick resin mask instead of a metal mask. This resin mask is finally stripped and removed, and an alkaline stripping composition (cleaning composition for stripping) is used for this purpose.

[0004] For example, Patent Document 1 proposes a dual-purpose cleaner capable of simultaneously cleaning solder flux and dry film resist, characterized in that the amount of benzyl alcohol added is within the range of 5 to 94 wt %, the amount of amine compound is within the range of 1 to 50 wt %, and the amount of water is within the range of 3 to 90 wt % relative to the total amount. Paragraph 0011 of the same document states that the electrical conductivity of the cleaner is preferably within the range of 1 to 250 μS / cm, and paragraph 0012 states that the cleaner is preferably in an emulsion state at room temperature (25°C). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-224165 Summary of the Invention [Problem to be solved by the invention]

[0006] When forming fine wiring on a printed circuit board or the like, the stripper composition is required to have high resin mask removability (stripping ability) in order to reduce not only the residue of the resin mask but also the residue of auxiliary agents contained in the solder or plating solution used in forming the fine wiring, pillars, and bumps. As wiring, pillars, and bumps become finer, the spaces between them also become finer, making it difficult to remove the resin mask present in the fine gaps. Therefore, a stripper composition is required to have higher resin mask removability (stripping ability). 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 surface of the substrate and a resin mask layer 1 present in the form of perforations in 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), conventional stripping compositions (cleaning compositions) have difficulty penetrating into the interface between the resin mask and the metal layer, making it difficult to strip the resin mask.

[0007] Therefore, the present disclosure provides a stripping agent composition that has excellent resin mask removability (peelability), a resin mask stripping method, and a method for producing electronic components. [Means for solving the problem]

[0008] In one embodiment, the present disclosure relates to a stripping agent composition that contains an alkaline agent, an organic solvent other than the alkaline agent, and water, and is an O / W type emulsion.

[0009] In one aspect, the present disclosure relates to a method for stripping a resin mask, comprising a step of stripping the resin mask from a substrate having the resin mask thereon using the stripper composition of the present disclosure.

[0010] In one aspect, the present disclosure relates to a method for manufacturing an electronic component, including the resin mask stripping method of the present disclosure. [Effects of the Invention]

[0011] According to one embodiment of the present disclosure, a stripper composition having excellent resin mask removal properties (stripping properties) can be provided. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram showing an example of the appearance of the substrate surface of a substrate to be cleaned. DETAILED DESCRIPTION OF THE INVENTION

[0013] [Removal agent composition] In one or more embodiments, the present disclosure is based on the finding that a resin mask can be efficiently removed (stripped) by using a stripper that is an O / W emulsion containing an alkali, an organic solvent, and water.

[0014] That is, in one aspect, the present disclosure relates to a stripper composition (hereinafter also referred to as "the stripper composition of the present disclosure") that contains an alkaline agent, an organic solvent other than the alkaline agent, and water and is an O / W type emulsion.

[0015] According to the present disclosure, a stripper composition having excellent resin mask removal properties (stripping properties) can be provided.

[0016] Although the details of the mechanism of action by which the effects of the present disclosure are manifested are still unclear, it is presumed as follows. It is generally believed that peeling of the resin mask is caused by interfacial stress due to the components of the stripping composition penetrating into the resin mask and causing the resin mask to swell. It is believed that the alkaline agent, organic solvent, and water in the stripper composition of the present disclosure penetrate into the resin mask, promoting dissociation of the alkali-soluble resin contained in the resin mask and further causing charge repulsion, thereby facilitating the removal of the resin mask. However, when the stripping composition is an aqueous solution in which an alkaline agent and an organic solvent are dissolved in water, the alkaline agent and the organic solvent are dispersed throughout the bulk of the cleaning composition, which is thought to make it difficult for them to efficiently adsorb to the interface of the alkali-soluble resin and penetrate into the interior. On the other hand, the liquid state of the stripper composition of the present disclosure is an O / W (oil-in-water) emulsion using water as a dispersion medium, and therefore the organic solvent containing the alkaline agent becomes locally concentrated, which is thought to significantly improve the adsorption of the alkali-soluble resin to the interface and the penetration into the interior, which is thought to enable efficient removal (peel-off) of the resin mask. However, the present disclosure need not be construed as being limited to this mechanism.

[0017] In one or more embodiments, the stripper composition of the present disclosure is a stripper composition (cleaning composition) for stripping a resin mask. In the present disclosure, stripping a resin mask may include dissolving the resin mask, removing the resin mask, and cleaning the resin mask. By using the stripper composition of the present disclosure for cleaning a substrate having a resin mask, the resin mask can be efficiently removed. Furthermore, by using the stripper 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 with a high yield.

[0018] In the present disclosure, a resin mask is a mask for protecting the surface of a material from treatments such as etching, plating, heating, etc., i.e., 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. Furthermore, resin masks are formed using resists whose physical properties, such as solubility in a developer, change when exposed to light or electron beams. Resists are broadly divided into negative and positive types based on how they react with light or electron beams. Negative resists have the property of decreasing their solubility in a developer when exposed to light, and the exposed portion of a layer containing negative resist (hereinafter also referred to as a "negative resist layer") is used as a resin mask after exposure and development. Positive resists have the property of increasing their solubility in a developer when exposed to light, and the exposed portion of a layer containing positive resist (hereinafter also referred to as a "positive resist layer") is removed after exposure and development, and the unexposed portion is used as a resin mask. By using a resin mask with such properties, fine connections on circuit boards, 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, and a negative resist film is preferred.

[0019] (liquid state) The liquid state of the stripper composition of the present disclosure is an O / W (oil-in-water) emulsion, and in one or more embodiments, the organic solvent is emulsified (dispersed) as emulsified particles (oil phase) in water (aqueous phase, continuous phase). In one or more embodiments, the alkaline agent may be present in both water and the organic solvent. The liquid state of the stripper composition can be determined from turbidity and electrical conductivity, specifically, by the method described in the Examples. The emulsification method for converting the liquid state of the stripper composition into an O / W emulsion is not particularly limited, and in one or more embodiments, mechanical emulsification methods such as those using a stirrer, homogenizer, or spray can be used. Furthermore, the emulsification may be performed by a single pass process or by a circulation operation.

[0020] (Turbidity) From the viewpoint of obtaining an O / W emulsion with high peeling properties, the turbidity of the release agent composition of the present disclosure is preferably 0.5 NTU or more, more preferably 10 NTU or more, and even more preferably 100 NTU or more. The turbidity of the release agent composition is a value at 60°C and can be measured using a turbidimeter, specifically, by the method described in the Examples.

[0021] (electrical conductivity) From the viewpoint of obtaining an O / W emulsion with high releasability, the electrical conductivity of the release agent composition of the present disclosure is preferably 1 S / m (10,000 μS / cm) or more, more preferably 3 S / m or more, and even more preferably 5 S / m or more. From the same viewpoint, it is preferably 50 S / m or less, more preferably 25 S / m or less, and even more preferably 10 S / m or less. The electrical conductivity of the release agent composition is a value at 60°C and can be measured using a benchtop electrical conductivity meter, specifically, by the method described in the Examples. The electrical conductivity value can be adjusted by the concentration of the alkaline agent and various additives.

[0022] (Component A: Alkaline) The stripper composition of the present disclosure contains an alkali (hereinafter also referred to as "component A"). Component A may be one type or a combination of two or more types. In one or more embodiments, from the viewpoint of improving the removability (peelability) of the resin mask and from the viewpoint of forming an O / W emulsion, Component A is preferably an alkali containing at least one selected from a quaternary ammonium hydroxide and an alkanolamine, and more preferably an alkali containing a quaternary ammonium hydroxide and an alkanolamine, or an alkali consisting of a quaternary ammonium hydroxide and an alkanolamine. From the same viewpoint, the total content of the quaternary ammonium hydroxide and the alkanolamine in Component A is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 7% by mass or more. As the quaternary ammonium hydroxide, from the viewpoint of improving the removability of the resin mask and from the viewpoint of preparing an O / W emulsion, a quaternary ammonium hydroxide having a total carbon atom number of 10 or less is preferably used, and tetramethylammonium hydroxide is more preferably used. The quaternary ammonium hydroxide may be one type or a combination of two or more types. As the alkanolamine, from the viewpoint of improving the removability (peelability) of the resin mask and from the viewpoint of preparing an O / W emulsion, an alkanolamine having a total carbon atom number of 6 or less is preferably used, and more preferably monoethanolamine. One type of alkanolamine may be used, or two or more types may be used in combination.

[0023] The content of Component A in the stripper composition of the present disclosure is preferably 5% by mass or more, more preferably 10% by mass or more, from the viewpoint of improving the removability (removal property) of the resin mask and from the viewpoint of forming an O / W emulsion, and from the same viewpoint, is preferably 25% by mass or less, more preferably 20% by mass or less. More specifically, the content of Component A in the stripper composition of the present disclosure is preferably 5% by mass or more and 25% by mass or less, more preferably 10% by mass or more and 20% 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. When component A contains a quaternary ammonium hydroxide, the content of the quaternary ammonium hydroxide in the stripper composition of the present disclosure is preferably 0.1% by mass or more, more preferably 1% by mass or more, and even more preferably 1.5% by mass or more from the viewpoint of improving resin mask removability (stripping ability), and is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 7% by mass or less from the viewpoint of improving resin mask removability (stripping ability) and waste liquid treatability. When two or more quaternary ammonium hydroxides are used in combination, the content of the quaternary ammonium hydroxides refers to the total content thereof. When component A contains an alkanolamine, the content of the alkanolamine in the stripper composition of the present disclosure is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 3% by mass or more, and still more preferably 7% by mass or more, from the viewpoint of improving resin mask removability (removal performance), and is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 13% by mass or less, from the viewpoints of improving resin mask removability (removal performance), waste liquid treatability, and suppressing damage to the substrate resin and the substrate metal. When two or more types of alkanolamines are used in combination, the content of alkanolamines refers to the total content thereof. When component A contains a quaternary ammonium hydroxide and an alkanolamine, the mass ratio of the content of the quaternary ammonium hydroxide to the content of the alkanolamine in the stripper composition of the present disclosure (quaternary ammonium hydroxide content / alkanolamine content) is preferably 0.1 or more, more preferably 0.15 or more, from the viewpoint of improving the removability (removability) of the resin mask and from the viewpoint of forming an O / W type emulsion, and from the same viewpoints, is preferably 5 or less, more preferably 1 or less, and even more preferably 0.5 or less.

[0024] (Component B: organic solvent) The stripper composition of the present disclosure contains an organic solvent (hereinafter also referred to as "component B") other than the alkaline agent (component A). Component B may be one type or a combination of two or more types. From the viewpoint of improving the removability (peelability) of the resin mask and from the viewpoint of forming an O / W emulsion, Component B preferably contains an organic solvent having a hydroxyl group, and more preferably is an organic solvent having a hydroxyl group. From the same viewpoints, the content of the organic solvent having a hydroxyl group in Component B is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more. Examples of organic solvents having a hydroxyl group include glycol ethers and aromatic alcohols. In one or more embodiments, the glycol ether 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, such as at least one selected from diethylene glycol monobutyl ether (BDG), ethylene glycol monobenzyl ether, ethylene glycol monopropyl ether, diethylene glycol monohexyl ether, ethylene glycol monophenyl ether, diethylene glycol diethyl ether, and triethylene glycol (TEG). One type of glycol ether may be used, or two or more types may be used in combination. In one or more embodiments, the aromatic alcohol may be a compound having a substituted aromatic ring and a hydroxyl group bonded to at least one of the substituents. Examples of the substituent include an alkyl group having 1 to 3 carbon atoms. Examples of the aromatic ring include a benzene ring and a naphthalene ring. From the viewpoint of improving the removability (peelability) of the resin mask, the number of carbon atoms in the aromatic alcohol is preferably 7 or more and preferably 9 or less. Examples of the aromatic alcohol include benzyl alcohol. The aromatic alcohol may be one type or a combination of two or more types. From the viewpoint of improving the removability (peelability) of the resin mask and from the viewpoint of forming an O / W emulsion, Component B preferably contains a glycol ether, and more preferably contains diethylene glycol monobutyl ether (BDG).

[0025] The content of component B in the stripper composition of the present disclosure is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 6% by mass or more, from the viewpoints of improving resin mask removability (removal performance) and forming an O / W emulsion. From the viewpoints of improving resin mask removability (removal performance), stability, and odor suppression, the content is 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 component B in the stripper composition of the present disclosure is preferably 1% by mass or more and 25% by mass or less, more preferably 3% by mass or more and 20% by mass or less, and even more preferably 6% by mass or more and 15% by mass or less. When component B is a combination of two or more types, the content of component B refers to the total content thereof. When component B contains a glycol ether, the content of the glycol ether in the stripper composition of the present disclosure is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 3% by mass or more, from the viewpoints of improving resin mask removability (removal performance) and forming an O / W emulsion. From the viewpoints of improving resin mask removability (removal performance), stability, and odor suppression, the content is preferably 12% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less. More specifically, the content of the glycol ether in the stripper composition of the present disclosure is preferably 0.5% by mass or more and 12% by mass or less, more preferably 1% by mass or more and 10% by mass or less, and even more preferably 3% by mass or more and 8% by mass or less. When two or more glycol ethers are used in combination, the content of the glycol ethers refers to the total content of the glycol ethers. When component B contains an aromatic alcohol, the content of the aromatic alcohol in the stripper composition of the present disclosure is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 3% by mass or more, from the viewpoints of improving resin mask removability (removal performance) and forming an O / W emulsion. From the viewpoints of improving resin mask removability (removal performance), stability, and odor suppression, the content is preferably 12% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less. More specifically, the content of the aromatic alcohol in the stripper composition of the present disclosure is preferably 0.5% by mass or more and 12% by mass or less, more preferably 1% by mass or more and 10% by mass or less, and even more preferably 3% by mass or more and 8% by mass or less. When two or more aromatic alcohols are used in combination, the content of the aromatic alcohols refers to the total content of the aromatic alcohols.

[0026] (Component C: water) In one or more embodiments, the stripper composition of the present disclosure may further contain water (hereinafter also referred to as "component C"). Examples of component C include ion-exchanged water, RO water, distilled water, pure water, and ultrapure water.

[0027] The content of component C in the stripper composition of the present disclosure can be the remainder excluding component A, component B, and optional components (other components described below). For example, the content of component C in the stripper composition of the present disclosure is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, from the viewpoints of improving resin mask removability (removal property), stability, and forming an O / W emulsion. From the same viewpoints, the content is preferably 99% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less. More specifically, the content of component C in the stripper composition of the present disclosure is preferably 50% by mass or more and 99% by mass or less, more preferably 60% by mass or more and 95% by mass or less, and even more preferably 70% by mass or more and 90% by mass or less.

[0028] In the present disclosure, the "content of each component of the stripper composition" refers to the content of each component at the time of use, i.e., at the time when the stripper composition starts to be used for cleaning (resin mask removal treatment). In one or more embodiments, the content of each component in the stripper composition of the present disclosure can be considered to be the blending amount of each component in the stripper composition of the present disclosure.

[0029] (Component D: Salt) In one or more embodiments, the stripper composition of the present disclosure may further contain a salt (hereinafter also referred to as "component D") from the viewpoint of improving the removability (removal property) of the resin mask and from the viewpoint of forming an O / W emulsion. From the same viewpoint, component D is preferably an organic salt. From the same viewpoint, the acid constituting the salt is preferably a polyvalent acid, such as 1-hydroxyethane-1,1-diphosphonic acid (HEDP) or carbonic acid. From the same viewpoint, the base constituting the salt is preferably a quaternary ammonium hydroxide. From the same viewpoint, the quaternary ammonium hydroxide is preferably a quaternary ammonium hydroxide having a total of 10 or less carbon atoms, more preferably tetramethylammonium hydroxide (TMAH). Examples of component D include a salt of TMAH and HEDP, and a salt of TMAH and carbonic acid.

[0030] When the stripper composition of the present disclosure contains component D, the content of component D in the stripper composition of the present disclosure is preferably 0.3 mol / L or more, more preferably 0.5 mol / L or more, and even more preferably 0.6 mol / L or more, from the viewpoint of improving the removability (removal property) of the resin mask and from the viewpoint of forming an O / W emulsion. From the same viewpoint, it is preferably 2 mol / L or less, more preferably 1.5 mol / L or less, and even more preferably 1 mol / L or less. More specifically, the content of component D in the stripper composition of the present disclosure is preferably 0.3 mol / L or more and 2 mol / L or less, more preferably 0.5 mol / L or more and 1.5 mol / L or less, and even more preferably 0.6 mol / L or more and 1 mol / L or less. When component D is a combination of two or more types, the content of component D refers to the total content thereof.

[0031] (Other ingredients) In one or more embodiments, the release agent composition of the present disclosure may further contain other components as needed to the extent that the effects of the present disclosure are not impaired. Examples of other components include solvents other than Components A to C, surfactants, chelating agents, thickeners, dispersants, rust inhibitors, polymeric compounds, solubilizers, antioxidants, preservatives, antifoaming agents, and antibacterial agents.

[0032] (pH) From the viewpoint of improving the removability (removal property) of the resin mask, the pH of the stripper composition of the present disclosure is preferably 10 or more, more preferably 11 or more, and even more preferably 12 or more, and from the viewpoint of suppressing damage to the substrate resin, it is preferably 18 or less, more preferably 17 or less, and even more preferably 16 or less. The pH of the stripper composition is a value at 25°C and can be measured using pH, specifically, by the method described in the Examples.

[0033] The stripper composition according to the present disclosure may be a so-called one-component type, in which all components are premixed and supplied to the market, or may be a so-called two-component type, in which components are mixed at the time of use.

[0034] (Method of producing the release agent composition) In one or more embodiments, the release agent composition of the present disclosure can be produced by blending Component A, Component B, Component C, and, if necessary, the optional components described above (Component D and other components) by a known method. For example, in one or more embodiments, the release agent composition of the present disclosure can be a composition comprising at least Component A, Component B, and Component C blended together. Therefore, the present disclosure relates to a method for producing a stripper composition, which includes a step of blending at least component A, component B, and component C. In the present disclosure, "blending" includes mixing component A, component B, component C, and, if necessary, the optional components described above (component D and other components) simultaneously or in any order. In the method for producing the release agent composition of the present disclosure, the preferred amount of each component may be the same as the preferred content of each component in the release agent composition of the present disclosure described above.

[0035] The stripper composition of the present disclosure may be in a form that is used for cleaning as is, or may be prepared as a concentrate to the extent that separation, precipitation, etc. do not occur and storage stability is not impaired. The stripper composition concentrate can be diluted at the time of use so that each component has the above-mentioned content (i.e., the content at the time of cleaning). The stripper composition concentrate 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 stripper composition concentrate refers to the state in which the stripper composition concentrate is diluted.

[0036] [Items to be cleaned] In one or more embodiments, the object to be cleaned is a substrate having a resin mask. Examples of the substrate include a glass epoxy multilayer substrate, a printed circuit board, a wafer, a copper plate, and an aluminum plate. The resin mask may be, for example, a negative resin mask or a positive resin mask, with a negative resin mask being preferred in terms of the ease with which the effects of the present disclosure are exerted. Examples of negative resin masks include negative dry film resists that have been subjected to exposure and / or development. In the present disclosure, a negative resin mask is one formed using a negative resist, and examples thereof include a negative resist layer that has been subjected to exposure and / or development. In the present disclosure, a positive resin mask is one formed using a positive resist, and examples thereof include a positive resist layer that has been subjected to exposure and / or development. The thickness of the resin mask is, for example, 5 μm to 35 μm or less.

[0037] In one or more embodiments, the substrate (object to be cleaned) having a resin mask may be 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, which can be formed by, for example, copper electroplating. The thickness of the metal layer is, for example, 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, the resin mask may be a resin mask (resin mask layer) present in the form of perforations in a metal layer (see FIG. 1). In one or more embodiments, the sides of the resin mask are surrounded by a metal layer. In one or more embodiments, the shape of the resin mask layer may be a polygonal (e.g., square, hexagonal, octagonal) columnar, cylindrical, or approximately cylindrical shape. The diameter of the resin mask layer (the diameter of the circumscribed 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 perforation (=interface line length between the resin mask and the metal layer / area of ​​the resin mask) can be 0.01 or more and 0.5 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 length of the circumference when the resin mask is circular when viewed from above. A new problem has been found in that conventional strippers have poor stripping properties when used on resin masks of such a structure on objects to be cleaned. In one or more embodiments, the stripper composition of the present disclosure can suitably remove resin masks of 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 to a metal layer in the form of perforations, as described above.

[0038] In one or more other embodiments, the substrate (object to be cleaned) having the resin mask may be, for example, an electronic component having a metal layer and a resin mask on its surface, or a manufacturing intermediate thereof. Examples of the electronic component include 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 manufacturing intermediate is an intermediate product in the manufacturing process of an electronic component, and includes an intermediate product after resin mask treatment. Specific examples of objects to be cleaned include electronic components in which wiring, connection terminals, etc. are formed on the surface of a substrate by undergoing at least one of soldering using a resin mask and plating (copper plating, aluminum plating, nickel plating, tin plating, etc.). In this disclosure, soldering refers to applying solder to the resin mask-free areas of the substrate and forming solder bumps by heating. In this disclosure, plating refers to performing at least one plating process selected from copper plating, aluminum plating, nickel plating, and tin plating on the resin mask-free areas of the substrate. The resin mask-free areas refer to areas in a resist pattern (patterned resin mask) formed by developing a resin mask laminated to a substrate, where the resin mask has been removed by the developing process.

[0039] In one or more other embodiments, the substrate (object to be cleaned) having the resin mask may include a substrate having a resin mask in a fine gap. For example, the substrate having a resin mask in a fine gap may include a substrate on which a non-cured resin mask is applied to the surface of the substrate by at least one of exposure and development, and then the non-cured resin mask is removed and a circuit pattern is formed by plating. The non-plated portion of the formed circuit pattern has a cured resin mask. In the present disclosure, in one or more embodiments, a gap refers to the distance between circuit patterns (thin line portions) (the spacing between adjacent thin line portions), and is also called a space (S). The thickness (plating thickness) of the thin line portions is, for example, 3 μm or more and 30 μm or less. The width of the thin line portions is also called a line (L). In one or more embodiments, a resin mask in a minute gap refers to a resin mask that exists in a space with a space width (S) of 10 μm or less. The thickness of the resin mask is, for example, 5 μm or more and 35 μm or less. An example of a resin mask present in a minute gap is a resin mask present in a space with a space width (S) of 4 to 7 μm.

[0040] [Removal method] In one aspect, the present disclosure relates to a method for stripping a resin mask (hereinafter also referred to as the "stripping method of the present disclosure"), which includes a step of stripping a resin mask from a substrate (object to be cleaned) having the resin mask thereon using a stripper composition of the present disclosure (hereinafter also simply referred to as the "stripping step"). Examples of the object to be cleaned in the stripping step include the above-mentioned objects to be cleaned.

[0041] The stripping method of the present disclosure includes a step of stripping a resin mask from a substrate (object to be cleaned) having the resin mask thereon using the stripper composition of the present disclosure (hereinafter, also simply referred to as a "stripping step"). In one or more embodiments, the stripping step includes contacting the object to be cleaned with the stripper composition of the present disclosure. According to the stripping method of the present disclosure, the resin mask can be efficiently removed.

[0042] Examples of a method for peeling a resin mask from an object to be cleaned using the stripper composition of the present disclosure, or a method for contacting an object to be cleaned with the stripper composition of the present disclosure, include a method of contacting the object by immersing the object in a cleaning bath containing the stripper composition, a method of contacting the object by spraying the stripper composition (shower method), and an ultrasonic cleaning method of irradiating the object with ultrasonic waves while immersed in the stripper composition. The stripper composition of the present disclosure can be used for cleaning as is without dilution. Examples of objects to be cleaned include the above-mentioned objects. The immersion time can be, for example, from 1 minute to 60 minutes, or even from 5 minutes to 30 minutes. The spray time can be, for example, from 1 minute to 60 minutes, or even from 3 minutes to 30 minutes.

[0043] In one or more embodiments, the stripping method of the present disclosure may include a step of contacting the object to be cleaned with the stripper composition of the present disclosure, 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 stripping method of the present disclosure can include a step of contacting the object to be cleaned with the stripper composition of the present disclosure and then rinsing with water.

[0044] In the stripping method of the present disclosure, ultrasonic waves are preferably applied when the stripper composition of the present disclosure comes into contact with the object to be cleaned, and the ultrasonic waves are more preferably relatively high frequency, from the viewpoint of making it easier for the stripper composition of the present disclosure to exert its stripping and cleaning power. 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.

[0045] In the stripping method of the present disclosure, the temperature of the stripper composition of the present disclosure is preferably 40°C or higher, more preferably 50°C or higher, from the viewpoint of easily exerting the stripping and cleaning power of the stripper composition of the present disclosure, and is preferably 70°C or lower, more preferably 60°C or lower, from the viewpoint of reducing the effect on the substrate.

[0046] [Electronic component manufacturing method] In one aspect, the present disclosure relates to a method for producing an electronic component (hereinafter also referred to as "the method for producing an electronic component of the present disclosure"), which includes the stripping method of the present disclosure. In one or more embodiments, the method for producing an electronic component of the present disclosure is a method for producing an electronic component, which includes a step (stripping step) of stripping a resin mask from a substrate (object to be cleaned) having the resin mask thereon using the stripper composition of the present disclosure. Examples of the object to be cleaned include the above-mentioned objects to be cleaned. Examples of the stripping method in the stripping step include methods similar to the above-mentioned stripping method of the present disclosure. According to the method for producing an electronic component of the present disclosure, the resin mask attached to the electronic component can be effectively peeled (removed), thereby enabling the production of highly reliable electronic components. Furthermore, by using the stripper composition of the present disclosure, the resin mask attached to the electronic component can be easily peeled off, thereby shortening the peeling time (cleaning time) and improving the production efficiency of the electronic component.

[0047] [kit] In one aspect, the kit of the present disclosure relates to a kit for producing the stripper composition 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 use in either the stripping method of the present disclosure or the method for producing an electronic component of the present disclosure. According to the kit of the present disclosure, a stripper composition having excellent resin mask stripping properties can be obtained. In one or more embodiments, the kit of the present disclosure includes a kit (two-component stripper composition) that contains a first liquid and a second liquid in a mutually unmixed state, with components A, B, and C contained in either or both of the first and second liquids, and in which the first and second liquids are mixed at the time of use. After the first and second liquids are mixed, they may be diluted with water (component C) as needed. The first and second liquids may each contain the above-mentioned optional components (component D, other components) as needed. [Example]

[0048] The present disclosure will be specifically described below using examples, but the present disclosure is not limited to these examples in any way.

[0049] 1. Preparation of Stripping Compositions of Examples 1 to 3 and Comparative Examples 1 and 2 The components shown in Table 1 were blended in the amounts (mass % or molar concentration, active ingredient) shown in Table 1 and mixed by stirring to prepare the release agent compositions of Examples 1 to 3 and Comparative Examples 1 to 3.

[0050] The following materials were used to prepare the stripper composition: (Component A) TMAH: Tetramethylammonium hydroxide [Resonac Corporation, 25% aqueous solution] MEA: Monoethanolamine [Nippon Shokubai Co., Ltd.] Diethanolamine [Tokyo Chemical Industry] (Component B) BDG: Diethylene glycol monobutyl ether [Nippon Nyukazai Co., Ltd.] Benzyl alcohol [Fujifilm Wako Pure Chemical Industries, Ltd.] (Component C) Water [pure water of 1 μS / cm or less produced using the Organo Corporation G-10DSTSET water purification system] (Component D) Salt of TMAH and HEDP [prepared by adding etidronic acid dropwise to a TMAH aqueous solution] TMAH and carbonic acid salt [prepared by bubbling carbon dioxide into a TMAH aqueous solution]

[0051] 2. Measurement of each parameter [pH of Stripping Composition] The pH of the stripping composition at 25°C was measured using a pH meter (HM-30G, manufactured by Toa Denpa Kogyo Co., Ltd.) 15 seconds after immersing the electrode of the pH meter in the treatment solution that had been stirred and homogenized. The results are shown in Table 1.

[0052] [Liquid state] The stripping composition was heated to 60°C, stirred to homogenize, and then the turbidity was measured to determine whether it was an emulsion according to the following criteria. The results are shown in Table 1. Emulsion: Turbidity 0.5 NTU or more Solubilization: Turbidity less than 0.5 NTU Furthermore, when the turbidity was 0.5 NTU or more and the electrical conductivity of the stripping composition was 1 S / m or more, it was determined to be an O / W type emulsion.

[0053] [Turbidity] The stripping composition is heated to 60°C, stirred to homogenize, and then the turbidity is measured using a turbidity meter ZD-2A (manufactured by Joman). The sample is placed in the turbidity meter and the reading is taken after 20 seconds. The results are shown in Table 1.

[0054] [Electrical conductivity] The stripping composition was heated to 60°C and stirred to homogenize, after which the conductivity was measured using a benchtop electrical conductivity meter "DS-72" (manufactured by HORIBA Corporation). The electrode was immersed in the stripping composition and the value was read 15 seconds later. The results are shown in Table 1.

[0055] 3. Evaluation Using the prepared stripper compositions of Examples 1 to 3 and Comparative Examples 1 and 2, the resin mask removability (stripping ability) was evaluated as follows. [Test piece for evaluating peelability] The test piece for evaluating peelability was 50 mm x 50 mm in size, and had a 15 μm-thick metal layer 2 formed by copper plating on the surface of a glass epoxy multilayer substrate with a thin copper film, as shown in Figure 1, and a 25 μm-thick resin mask layer 1 made of negative dry film resist in circular areas with a diameter of 100 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. There were 3,000 perforations. [Resin mask removability (peelability)] 3 kg of the stripping composition was added to a 5-L stainless steel beaker. The beaker was heated to 60°C, and the test piece was sprayed for 275 seconds while circulating the composition using a box-type spray washer equipped with a one-fluid nozzle (full cone type) J020 (Ikeuchi Co., Ltd.) (pressure: 0.2 MPa, spray distance: 8 cm). The test piece was then rinsed with water for 30 seconds and then dried with nitrogen. Using a digital microscope (VHX-6000, Keyence Corporation), the test piece after the spray treatment was visually observed at 300x magnification to measure the rate of resin mask residue generation. A lower value indicates better resin mask removability (peelability). The results are shown in Table 1.

[0056] [Table 1]

[0057] As shown in Table 1, it was found that the stripper compositions of Examples 1 to 3, which are in an O / W emulsion state, have superior resin mask removability (stripping ability) compared to Comparative Example 1, which is in a solubilized state, and Comparative Example 2, which is in an emulsion state. [Industrial Applicability]

[0058] According to the present disclosure, a stripper composition capable of efficiently removing a resin mask can be provided. Furthermore, use of the stripper composition of the present disclosure makes it possible to improve the performance and reliability of manufactured electronic components, thereby improving the productivity of semiconductor devices. [Explanation of symbols]

[0059] 1 Resin mask layer (dry film resist) 2 Metal layer (metal plating layer)

Claims

1. A stripper composition for stripping a resin mask, comprising: The method comprises the steps of: (a) preparing a coating solution containing an alkaline agent; (b) preparing an organic solvent other than the alkaline agent; (c) preparing a coating solution containing an alkaline agent; (d) preparing an organic solvent other than the alkaline agent; (e) preparing a coating solution containing an alkaline agent; (f) preparing a coating solution containing an alkaline agent; (g) preparing a coating solution containing an alkaline agent; (h) preparing a coating solution containing an alkaline agent; (i) preparing a coating solution containing an alkaline agent; (ii) preparing a coating solution containing an alkaline the acid constituting the salt is a polyvalent acid, The stripping composition is an O / W emulsion.

2. The stripper composition of claim 1 , wherein the alkaline agent comprises a quaternary ammonium hydroxide and an alkanolamine.

3. The stripper composition of claim 2 wherein the alkanolamine is monoethanolamine.

4. The stripping composition according to claim 1, which has an electrical conductivity of 1 S / m or more.

5. A method for stripping a resin mask, comprising the step of stripping the resin mask from a substrate having the resin mask thereon by using the stripping composition according to any one of claims 1 to 4.

6. A method for manufacturing an electronic component, comprising the method for removing a resin mask according to claim 5.

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