Cleaning agent composition for flux residue removal

Abstract

To provide a cleaning agent composition for flux residue removal that has excellent properties for removing both discolored metal and flux residues after a heat treatment at or above 200°C.SOLUTION: In one aspect, the present disclosure relates to a cleaning agent composition for flux residue removal, the cleaning agent composition comprising: at least one organic solvent (component A) selected from among compounds represented by formula (I), R1-O-(AO)n-R2, and compounds represented by formula (II), R3-CH2OH; an imidazole compound (component B) represented by formula (III) in the figure; carboxylic acid (component C); and water (component D).SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a cleaning agent composition for removing flux residues and a cleaning method using the cleaning agent composition.

Background Art

[0002] For electrodes forming circuits of electronic substrates such as semiconductor packages, metals such as copper and copper alloys are used in order to reduce manufacturing costs.

[0003] As a method of mounting a printed wiring board, surface mounting with improved mounting density is widely adopted. In order to improve the mounting density, a technique is known in which a nano metal paste is applied between a wiring on a substrate and a terminal of an electronic element, and the nano metal is melted and solidified by heating to bond between the wiring on the substrate and the terminal of the electronic element.

[0004] On the other hand, a technique for cleaning solder flux of electronic components after soldering is known. For example, Patent Document 1 proposes a cleaning agent composition for removing flux residues, which contains a solvent and an amine having a polar term δp of Hansen solubility parameter of 7.8 or less and a specific diphosphonic acid. Patent Document 2 proposes a cleaning method including a step of cleaning an object to be cleaned having flux residues with a cleaning agent composition, wherein the cleaning agent composition contains an organic solvent and a compound having an alkyl group having 1 to 4 carbon atoms on a nitrogen atom of an imidazole ring or a piperazine ring. Patent Document 3 proposes a cleaning agent composition comprising N-methyl-2-pyrrolidone containing 0 to 30% by weight of water and one or more compounds selected from compounds of phosphines, phenols, imidazolidones, imidazoles or fluorenes. Patent Document 4 proposes a cleaning composition solution with a pH of 8 or higher for cleaning a semiconductor device substrate that has Cu wiring and a low dielectric constant insulating film on the substrate surface and has undergone chemical mechanical polishing. The cleaning composition solution contains tetramethylammonium hydroxide, diamines selected from ethylenediamine and 1,2-diaminopropane, organic acids selected from oxalic acid, citric acid, tartaric acid, malic acid, and picolinic acid, histidine or its derivative, at least one selected from benzotriazole, imidazole, triazole, tetrazole, and its derivatives, and water. Patent Document 5 proposes a cleaning composition containing about 0.5 to 20% by weight of hydroxylamine, a chelating agent containing at least two nitrogen-containing groups in an amount of about 0.01 to 1% by weight, an alkylene glycol, and water, with the pH of the composition being about 7.5 to 11, and the composition being configured to remove residues from a semiconductor substrate, where the semiconductor substrate contains a cobalt-containing interconnection body. Patent Document 6 proposes a cleaning composition containing hydroxylamine, alkanolamine, alkylene glycol, and water, with a pH of 7 or higher and 11 or lower.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0006] When applying a nano metal paste containing an acid (flux component) and melting and solidifying the nano metal by heating to bond between wiring on a substrate and terminals of an electronic element, a step of holding the substrate at a high temperature of 200°C or higher is required to melt the metal. If flux residues mainly composed of an acid remain on the substrate after this step, it is necessary to wash them. In addition, depending on the type of metal on the substrate surface or metal member, the surface may oxidize and discolor when held at a high temperature of 200°C or higher. Therefore, a cleaning agent composition capable of removing the discolored portion, that is, the oxidized metal (metal oxide), by heat treatment at 200°C or higher is required.

[0007] Therefore, the present disclosure provides a cleaning agent composition and a cleaning method for removing flux residues, which are excellent in removability of both discolored metal and flux residues after heat treatment at 200°C or higher.

Means for Solving the Problems

[0008] In one aspect, the present disclosure relates to a cleaning agent composition for removing flux residues, which includes at least one organic solvent (component A) selected from a compound represented by the following formula (I) and a compound represented by the following formula (II), an imidazole compound (component B) represented by the following formula (III), a carboxylic acid (component C), and water (component D). R 1 -O-(AO) n -R 2 (I) In the above formula (I), R 1 is a phenyl group or an alkyl group having 1 to 8 carbon atoms, R 2 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, AO is an ethylene oxide group or a propylene oxide group, n is the number of moles of AO added, and is an integer of 1 or more and 3 or less. R 3 -CH2OH (II) In the above formula (II), R 3is a phenyl group, benzyl group, cyclohexyl group, furyl group, tetrahydrofuryl group, furfuryl group or tetrahydrofurfuryl group.

Chemical formula

[0009] In one aspect, the present disclosure relates to a cleaning method including a cleaning step of cleaning an object to be cleaned having flux residue with the cleaning agent composition for removing flux residue of the present disclosure, wherein the object to be cleaned is a substrate that has been subjected to a heating step at 200°C or higher.

Advantages of the Invention

[0010] According to the present disclosure, it is possible to provide a cleaning agent composition for removing flux residue and a cleaning method that are excellent in the removability of both discolored metal and flux residue after heat treatment at 200°C or higher.

Modes for Carrying Out the Invention

[0011] Based on the finding that by combining at least one organic solvent (component A) selected from the compounds represented by the above formula (I) and the compounds represented by the above formula (II), the imidazole compound (component B) represented by the above formula (III), a carboxylic acid (component C), and water (component D), it is possible to improve the removability of both discolored metal (metal oxide) and flux residue after heat treatment at 200°C or higher. Further, based on the finding that when a carboxylic acid having 8 or more carbon atoms is used as component C, damage to other members such as members of the apparatus (for example, iron members such as cleaning tanks, cleaning pipes, nozzles, etc.) and members provided on the substrate (for example, iron members such as covers, etc.) can be reduced.

[0012] That is, in one aspect, the present disclosure relates to a cleaning agent composition for removing flux residues remaining after joining between two members by a sintering process, the cleaning agent composition including at least one organic solvent (component A) selected from the compound represented by the above formula (I) and the compound represented by the above formula (II), an imidazole compound (component B) represented by the above formula (III), a carboxylic acid (component C), and water (component D) (hereinafter, also referred to as "the cleaning agent composition of the present disclosure").

[0013] According to the present disclosure, it is possible to provide a cleaning agent composition for removing flux residues that is excellent in removability of both discolored metal (metal oxide) and flux residues after heat treatment at 200 °C or higher. Further, in one or more embodiments, the present disclosure can provide a cleaning agent composition for removing flux residues that can further reduce damage to other members such as iron members.

[0014] Although the details of the action mechanism of the effect expression of the present disclosure are unclear, it is speculated as follows. In the cleaning agent composition of the present disclosure, a specific imidazole compound (component B) adsorbs to the discolored metal (for example, metal oxide such as copper oxide) to form an imidazole compound metal complex (for example, imidazole compound copper complex). Complexes such as imidazole compound copper complexes have low affinity with general organic solvents, and diffusion from the surface of metal oxides such as copper oxide does not proceed, and the removal of metal oxides such as copper oxide is not completed. However, in the present disclosure, as a result of a specific organic solvent (component A) solvating a complex such as an imidazole compound copper complex and forming a cluster with high affinity, diffusion proceeds into the specific organic solvent (component A). Due to this effect, it is considered that the dissolution reaction of the metal oxide proceeds and the removal of metal oxides such as copper oxide is completed. Also, in terms of flux residue removability, it is considered that the solubility of the flux residue is increased by the neutralization reaction between the rosin acid contained in the flux residue and the imidazole compound. Furthermore, the cleaning composition of the present disclosure contains a carboxylic acid (Component C), which forms a carboxylic acid-imidazole compound complex, and is considered to promote the removal of metal oxides because it has higher solvent versatility and faster diffusion. When a carboxylic acid having 8 or more carbon atoms is used, selective adsorption to metal species occurs, and it is considered that damage to other members is reduced. In addition, in the present disclosure, by using a specific organic solvent (Component A) in the presence of a specific imidazole compound (Component B) and a carboxylic acid (Component C), it is considered that the solubility of the flux residue is further improved, and the flux residue can be satisfactorily cleaned (removed). From the above, it is considered that the cleaning composition of the present disclosure exhibits good flux residue removability and removability of discolored metals (metal oxides). And it is considered that damage to other members such as members provided on the members of the apparatus (for example, iron members such as cleaning tanks, cleaning pipes, nozzles, etc.) and members provided on the substrate (for example, iron members such as covers, etc.) can be reduced. However, the present disclosure may not be construed as being limited to this mechanism.

[0015] The "flux" in the present disclosure is a flux used to join two members by a sintering process (for example, a process of maintaining at a high temperature of 200 °C or higher) in one or more forms. For example, it is used for joining a heat sink and a semiconductor element, or joining a heat sink and a substrate. The flux is a joining aid mainly composed of an acid in one or more embodiments. The "flux residue" in the present disclosure refers to a residue derived from the flux remaining on the substrate after forming solder bumps using the flux and / or the substrate after soldering using the flux. For example, when other components (for example, semiconductor chips, chip-type capacitors, other circuit boards, etc.) are laminated and mounted on a circuit board, a space (gap) is formed between the circuit board and the other components. The flux used for the mounting may also remain in this gap as a flux residue after soldering by reflow or the like. The "cleaning agent composition for removing flux residues" in the present disclosure refers to a cleaning agent composition for removing flux residues remaining after joining between two members by a sintering process in one or more embodiments.

[0016] [Component A: Organic solvent] At least one organic solvent selected from the compound represented by the following formula (I) and the compound represented by the following formula (II) contained in the cleaning agent composition of the present disclosure (hereinafter also referred to as "Component A") may be one kind or a combination of two or more kinds.

[0017] [Compound represented by formula (I)] R 1 -O-(AO) n -R 2 (I) In the above formula (I), R 1 is a phenyl group or an alkyl group having 1 to 8 carbon atoms. From the viewpoint of improving the flux residue removability, a phenyl group or an alkyl group having 4 to 6 carbon atoms is preferable, and an alkyl group having 4 to 6 carbon atoms is more preferable. R 2 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. From the viewpoint of ease of rinsing, a hydrogen atom is preferable, and from the viewpoint of improving the flux residue removability, an alkyl group having 2 to 4 carbon atoms is preferable, and an n-butyl group is more preferable. AO is an ethyleneoxy group (EO) or a propyleneoxy group (PO). From the same viewpoint, an ethyleneoxy group is preferable. n is the number of moles of addition of AO and represents an integer of 1 or more and 3 or less. From the same viewpoint, 1 or 2 is preferable, and 2 is more preferable.

[0018] Examples of the compound represented by the formula (I) include monophenol glycol ethers such as ethylene glycol monophenyl ether (PHG-S, 2-phenoxyethanol), diethylene glycol monophenyl ether, and propylene glycol monophenyl ether; monobenzyl glycol ethers such as ethylene glycol monobenzyl ether, diethylene glycol monobenzyl ether, and propylene glycol monobenzyl ether; monoalkyl ethers such as ethylene glycol monoalkyl ether having an alkyl group with 1 to 8 carbon atoms, diethylene glycol monoalkyl ether, and triethylene glycol monoalkyl ether; dialkyl ethers such as ethylene glycol dialkyl ether having an alkyl group with 1 to 8 carbon atoms and an alkyl group with 1 to 4 carbon atoms, diethylene glycol dialkyl ether, and triethylene glycol dialkyl ether; phenylalkyl ethers such as ethylene glycol phenylalkyl ether having a phenyl group and an alkyl group with 1 to 4 carbon atoms, diethylene glycol phenylalkyl ether, and triethylene glycol phenylalkyl ether; and the like. Among these, as the compound represented by the formula (I), from the viewpoint of improving the removal property of flux residues, at least one selected from ethylene glycol monophenyl ether (PHG-S), diethylene glycol monobutyl ether (BDG), dipropylene glycol monobutyl ether (BFDG), diethylene glycol dibutyl ether (DBDG), and diethylene glycol diethyl ether is preferable, and diethylene glycol monobutyl ether (BDG) is more preferable.

[0019] <Compound represented by formula (II)> R 3 -CH2OH (II) In the above formula (II), R 3is a phenyl group, benzyl group, cyclohexyl group, furyl group, tetrahydrofuryl group, furfuryl group or tetrahydrofurfuryl group. From the viewpoint of improving the removal property of flux residues, a phenyl group, cyclohexyl group or tetrahydrofuryl group is preferable, and a phenyl group or tetrahydrofuryl group is more preferable.

[0020] Examples of the compound represented by the formula (II) include at least one selected from benzyl alcohol, phenethyl alcohol, cyclohexanemethanol, furfuryl alcohol, and tetrahydrofurfuryl alcohol. From the viewpoint of improving the removal property of flux residues, at least one selected from benzyl alcohol, furfuryl alcohol, and tetrahydrofurfuryl alcohol is preferable, and at least one selected from benzyl alcohol (BzOH) and tetrahydrofurfuryl alcohol is more preferable.

[0021] From the viewpoint of improving the removability of discolored metals, the content of component A when using the cleaning composition of the present disclosure is preferably 10% by mass or more, more preferably 20% by mass or more, further preferably more than 25% by mass, and further preferably 40% by mass or more. From the viewpoint of improving the metal solubility of component B, it is preferably 90% by mass or less, more preferably 85% by mass or less, and further preferably 80% by mass or less. More specifically, the content of component A when using the cleaning composition of the present disclosure is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 85% by mass or less, further preferably more than 25% by mass and 80% by mass or less, and even more preferably 40% by mass or more and 80% by mass or less. When component A is a combination of two or more, the content of component A refers to their total content.

[0022] [Component B: Imidazole compound represented by formula (III)] The imidazole compound represented by the following formula (III) (hereinafter also referred to as "component B") contained in the cleaning composition of the present disclosure may be one kind or a combination of two or more kinds. [Chemical formula]

[0023] In the above formula (III), R 4 , R 5 , R 6 and R 7 each independently represents a hydrogen atom, a halogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a phenyl group, an aldehyde group, a carboxy group, an aminoethyl group, an aminopropyl group, an acetyl group, a hydroxyethyl group or a hydroxypropyl group. R 4 , R 5 , R 6 and R 7 each independently, from the viewpoint of improving the removability of the discolored metal, are preferably a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a phenyl group, an aminoethyl group, an aminopropyl group, an acetyl group, a hydroxyethyl group, or a hydroxypropyl group, more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, or a hydroxyethyl group, and still more preferably a methyl group or an ethyl group.

[0024] As component B, from the viewpoint of improving the removability of both discolored metal and flux residues, at least one selected from imidazole, 1-methylimidazole, 1-ethylimidazole, 1-propylimidazole, 1-isopropylimidazole, 1-acetylimidazole, 1-aminopropylimidazole, 1-hydroxyethylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-isopropylimidazole, 2-acetylimidazole, 2-aminopropylimidazole, 2-hydroxyethylimidazole, 4-methylimidazole, 4-ethylimidazole, 4-propylimidazole, 4-isopropylimidazole, 4-acetylimidazole, 4-aminopropylimidazole, 4-hydroxyethylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, and 2-ethyl-4-methylimidazole can be mentioned. Among these, from the same viewpoint, component B is preferably at least one selected from 1-methylimidazole, 2-methylimidazole, 1-isobutyl-2-methylimidazole, and 2-ethyl-4-methylimidazole.

[0025] When using the cleaning composition of the present disclosure, the content of component B is preferably 0.5% by mass or more, more preferably 0.75% by mass or more, still more preferably 1% by mass or more, and from the same viewpoint, preferably 15% by mass or less, more preferably 10% by mass or less, still more preferably 8% by mass or less, from the viewpoint of improving the removability of both discolored metal and flux residues. More specifically, the content of component B when using the cleaning composition of the present disclosure is preferably 0.5% by mass or more and 15% by mass or less, more preferably 0.75% by mass or more and 10% by mass or less, still more preferably 1% by mass or more and 10% by mass or less. Further more specifically, the content of component B when using the cleaning composition of the present disclosure is more preferably 0.75% by mass or more and 8% by mass or less, still more preferably 1% by mass or more and 8% by mass or less. When component B is a combination of two or more types, the content of component B refers to their total content.

[0026] In the cleaning composition of the present disclosure, the mass ratio (B / A) of component B to component A (content of component B (mass%) / content of component A (mass%)) is preferably 0.005 or more, more preferably 0.008 or more, still more preferably 0.01 or more, still more preferably 0.03 or more, still more preferably 0.05 or more, from the viewpoint of improving the removability of discolored metal. From the same viewpoint, it is preferably 1.0 or less, more preferably 0.5 or less, still more preferably 0.3 or less, still more preferably 0.2 or less, still more preferably 0.1 or less. More specifically, the mass ratio (B / A) is preferably 0.005 or more and 1.0 or less, more preferably 0.008 or more and 0.5 or less, still more preferably 0.01 or more and 0.3 or less, 0.03 or more and 0.2 or less, or 0.01 or more and 0.1 or less.

[0027] [Component C: Carboxylic acid] The carboxylic acid (hereinafter also referred to as "component C") contained in the cleaning composition of the present disclosure may be one kind or a combination of two or more kinds.

[0028] The number of carbon atoms of component C is preferably 2 or more from the viewpoint of improving the removability of both discolored metal and flux residue, and preferably 8 or more from the viewpoint of reducing damage to other members such as iron members. From the viewpoints of improving the removability of both discolored metal and flux residue and reducing damage to other members such as iron members, 22 or less is preferable, 18 or less is more preferable, and 16 or less is still more preferable. More specifically, the number of carbon atoms of component C is preferably 2 or more and 22 or less, or 8 or more and 22 or less, more preferably 8 or more and 18 or less, still more preferably 8 or more and 16 or less.

[0029] As component C, from the viewpoints of improving the removability of both discolored metal and flux residue and reducing damage to other members such as iron members, carboxylic acids having 8 or more carbon atoms are preferable. For example, at least one selected from caprylic acid, capric acid, dodecanedioic acid, lauric acid, myristic acid, palmitic acid, oleic acid, stearic acid, and behenic acid can be mentioned.

[0030] When using the cleaning composition of the present disclosure, the content of component C is preferably 0.5% by mass or more, more preferably 3.5% by mass or more, from the viewpoint of improving the removability of both discolored metal and flux residue, and preferably 10% by mass or less, more preferably 5% by mass or less, from the same viewpoint. More specifically, the content of component C when using the cleaning composition of the present disclosure is preferably 0.5% by mass or more and 10% by mass or less, more preferably 3.5% by mass or more and 5% by mass or less. When component C is a combination of two or more types, the content of component C refers to their total content.

[0031] In the cleaning composition of the present disclosure, the mass ratio (C / A) of component C to component A (content of component C (% by mass) / content of component A (% by mass)) is preferably 0.0001 or more, more preferably 0.005 or more, still more preferably 0.01 or more, from the viewpoint of improving the removability of discolored metal, and preferably 1.0 or less, more preferably 0.5 or less, still more preferably 0.1 or less, even more preferably 0.05 or less, from the same viewpoint. More specifically, the mass ratio (C / A) of component C to component A is preferably 0.0001 or more and 1.0 or less, more preferably 0.005 or more and 0.5 or less, still more preferably 0.01 or more and 0.1 or less, even more preferably 0.01 or more and 0.05 or less.

[0032] In the cleaning composition of the present disclosure, the mass ratio (B / C) of component B to component C (content of component B (% by mass) / content of component C (% by mass)) is preferably 0.01 or more, more preferably 0.1 or more, still more preferably 0.5 or more, from the viewpoint of improving the removability of discolored metal, and preferably 25 or less, more preferably 15 or less, still more preferably 5 or less, even more preferably 2 or less, from the same viewpoint. More specifically, the mass ratio (B / C) of component B to component C is preferably 0.01 or more and 25 or less, more preferably 0.1 or more and 15 or less, still more preferably 0.5 or more and 5 or less.

[0033] [Component D: Water] Examples of the water (hereinafter also referred to as "component D") contained in the cleaning composition of the present disclosure include ion-exchanged water, RO water (reverse osmosis membrane-treated water), distilled water, pure water, ultrapure water, and the like. When using the cleaning composition of the present disclosure, the content of component D is preferably 0.5% by mass or more, more preferably 5% by mass or more, from the viewpoint of improving the removability of discolored metal. From the viewpoint of improving the removability of both discolored metal and flux residue, it is preferably 20% by mass or less, and more preferably 10% by mass or less. More specifically, when using the cleaning composition of the present disclosure, the content of component D is preferably 0.5% by mass or more and 20% by mass or less, and more preferably 5% by mass or more and 10% by mass or less.

[0034] [Component E: Amine represented by formula (IV)] In one or more embodiments, the cleaning composition of the present disclosure may further contain an amine represented by formula (IV) (hereinafter also referred to as "component E"). Component E may be one kind or a combination of two or more kinds. [Chemical formula] In the above formula (IV), R 8 represents a hydrogen atom, an alkyl group, a phenyl group, a benzyl group, a hydroxyethyl group, a hydroxypropyl group, or an aminoethyl group, and R 9 represents a hydrogen atom, a hydroxyethyl group, a hydroxypropyl group, or an alkyl group, and R 10 represents a hydroxyethyl group, a hydroxypropyl group, or an alkyl group. Examples of the alkyl group include an alkyl group having 1 to 6 carbon atoms from the viewpoint of improving the removability of both discolored metal and flux residue.

[0035] As component E, for example, at least one selected from alkanolamines such as 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, N-(β-aminoethyl)diisopropanolamine, and N,N-dibutylethanolamine (dibutylaminoethanol); and aromatic amines such as dimethylbenzylamine; can be mentioned. Among these, from the viewpoint of improving the removability of both the discolored metal and the flux residue, component E is preferably at least one selected from diisopropanolamine and N,N-dibutylethanolamine (dibutylaminoethanol).

[0036] When the cleaning composition of the present disclosure contains component E, from the viewpoint of improving the flux residue removability, the content of component E during the use of the cleaning composition of the present disclosure is preferably 0.2% by mass or more, more preferably 0.5% by mass or more, still more preferably 1% by mass or more, and from the same viewpoint, preferably 15% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less. More specifically, the content of component E during the use of the cleaning composition of the present disclosure is preferably 0.2% by mass or more and 15% by mass or less, more preferably 0.5% by mass or more and 10% by mass or less, still more preferably 1% by mass or more and 5% by mass or less. When component E is a combination of two or more, the content of component E refers to their total content.

[0037] [Other Components] The cleaning composition of the present disclosure can, within the scope not impairing the effects of the present disclosure, optionally contain at least one selected from organic solvents other than component A, basic substances other than component B, fatty acids other than component C, chelating agents, rust preventives, thickeners, dispersants, pH adjusters, polymer compounds, surfactants, solubilizers, preservatives, bactericides, antibacterial agents, antifoaming agents, and antioxidants, which are usually used in cleaning agents, as appropriate.

[0038] In one or more embodiments, the cleaning composition of the present disclosure can be substantially free of diphosphonic acid. For example, the content of diphosphonic acid when using the cleaning composition of the present disclosure is preferably less than 0.1% by mass, more preferably 0.01% by mass or less, and still more preferably 0% by mass (i.e., not contained).

[0039] [Method for manufacturing a cleaning composition] The cleaning composition of the present disclosure can be produced, for example, by blending component A, component B, component C, component D, and optionally optional components (component E and other components) by a known method. In one or more embodiments, the cleaning composition of the present disclosure can be made by blending at least component A, component B, component C, and component D. Therefore, the present disclosure relates to, in one aspect, a method for manufacturing a cleaning composition, which includes a step of blending at least component A, component B, component C, and component D. In the present disclosure, "blending" includes mixing component A, component B, component C, component D, and optionally optional components (component E and other components) simultaneously or in any order. In the method for manufacturing the cleaning composition of the present disclosure, the blending amount of each component can be the same as the content of each component when using the cleaning composition of the present disclosure described above. In the present disclosure, "the content of each component when using the cleaning composition" refers to the content of each component at the time of cleaning, that is, at the time when the use of the cleaning composition for cleaning is started.

[0040] [pH of the cleaning composition] From the viewpoint of improving the removability of both metal discoloration and flux residues, the pH of the cleaning composition of the present disclosure is preferably 5 or more, more preferably 6 or more, and from the same viewpoint, preferably 12 or less, more preferably 11 or less, and even more preferably 10 or less. More specifically, the pH of the cleaning composition of the present disclosure is preferably 5 or more and 12 or less, more preferably 6 or more and 11 or less, and even more preferably 6 or more and 10 or less. The pH can be adjusted, if necessary, using inorganic acids such as nitric acid and sulfuric acid, organic acids such as oxycarboxylic acids, polycarboxylic acids, aminopolycarboxylic acids, and amino acids, and their metal salts, ammonium salts, ammonia, sodium hydroxide, potassium hydroxide, amines, carboxylic acids (Component C), etc. In the present disclosure, the pH of the cleaning composition is the pH at the time of use of the cleaning composition at 25°C and can be measured by the method described in the examples.

[0041] In one or more embodiments, the cleaning composition of the present disclosure is used for cleaning an object to be cleaned having flux residues, particularly an object to be cleaned having flux residues remaining after joining two members by a sintering process. In one or more embodiments, the cleaning composition of the present disclosure can be used as a cleaning agent for removing flux residues from an object to be cleaned having flux residues. Therefore, the present disclosure relates, in one aspect, to the use of a cleaning composition (i.e., the cleaning composition of the present disclosure) containing Component A, Component B, Component C, and Component D as a flux residue cleaning agent. In one or more other embodiments, the cleaning composition of the present disclosure can be used as a remover for removing flux residues from an object to be cleaned having flux residues. Therefore, the present disclosure relates, in other aspects, to the use of the cleaning composition of the present disclosure as a flux residue remover.

[0042] [Object to be cleaned] In one or more embodiments, the object to be cleaned includes a substrate that has been subjected to a heating step at 200° C. or higher, and in one or more embodiments, it may have a metal member containing copper on the substrate. The step of heating at 200° C. or higher is, in one or more embodiments, a step of holding at a high temperature of 200° C. or higher (sintering step). In one or more embodiments, the object to be cleaned includes an object to be cleaned having a flux residue. As the object to be cleaned having a flux residue, in one or more embodiments, there is a substrate having a flux residue that has been subjected to a heating step (sintering step) at 200° C. or higher after applying a slurry containing a flux between the substrate and the metal member or between two metal members on the substrate. Therefore, in one aspect, the present disclosure relates to the use of the cleaning agent composition of the present disclosure in the cleaning of a substrate having a flux residue that has been subjected to a heating step (sintering step) at 200° C. or higher after applying a slurry containing a flux between the substrate and the metal member or between two metal members on the substrate. In the sintering step, the heating temperature is, for example, 200° C. to 350° C. The heating time is, for example, 3 minutes to 5 hours. From the viewpoint of exhibiting detergency against the denaturation of the flux by heat, the object to be cleaned is preferably an object to be cleaned that has been heated for 1 hour or more. In one or more embodiments, the substrate surface and / or the metal member of the object to be cleaned includes a portion where the metal has discolored due to heating, that is, a portion where the metal has been oxidized (metal oxide). In one or more embodiments, the flux contains an acid as a main component. Examples of the acid include organic acids such as abietic acid. In one or more embodiments, the slurry containing the flux may further contain metal particles. The metal particles are preferably metal particles having a sintering temperature (curing temperature) of 300°C or lower, and examples thereof include tin, copper, silver, or mixed metals thereof, etc. Copper, silver, or mixed metals thereof are preferred, and silver is more preferred. The metal particles serve as a bonding material capable of bonding between the substrate and the metal member or between two metal members on the substrate in one or more embodiments. The slurry containing the flux can be used as a die attach paste in one or more embodiments. When the slurry containing the flux further contains metal particles, the slurry can be used as a conductive die attach paste in one or more embodiments. In one or more embodiments, the metal member is fixed on the substrate. In one or more embodiments, the metal of the metal member includes metals such as copper and iron. Examples of the metal member include a heat sink, an electric circuit, etc. In one or more embodiments, examples of the substrate include a substrate having a metal surface, such as a copper plate, a steel plate, a stainless steel plate, etc. In one or more embodiments, the substrate surface and / or the metal member of the object to be cleaned contains copper.

[0043] [Washing method] In one aspect, the present disclosure relates to a cleaning method (hereinafter, also referred to as "the cleaning method of the present disclosure") including a cleaning step of cleaning an object to be cleaned having flux residues with the cleaning agent composition of the present disclosure. Examples of the object to be cleaned include the objects to be cleaned described above. The cleaning step includes bringing the object to be cleaned having flux residues into contact with the cleaning agent composition of the present disclosure in one or more embodiments. According to the cleaning method of the present disclosure, both the discolored metal (metal oxide) and the flux residues after high-temperature treatment at 200°C or higher can be efficiently removed. In one or more embodiments, the cleaning step includes removing discolored metal using the cleaning agent composition of the present disclosure. Accordingly, in one aspect, the present disclosure relates to the use of the cleaning agent composition of the present disclosure for removing discolored metal and flux residues. The discolored metal includes, in one or more embodiments, the oxidized portion (metal oxide) of the metal due to heating. Examples of the method for cleaning the object to be cleaned with the cleaning agent composition of the present disclosure, or the method for bringing the cleaning agent composition of the present disclosure into contact with the object to be cleaned include, for example, a method of immersing and contacting in a bath of an ultrasonic cleaning device, a method of injecting the cleaning agent composition in a spray form for contact (shower method), and the like. In one or more embodiments, the cleaning agent composition of the present disclosure can be used for cleaning as it is without dilution. In one or more embodiments, the cleaning step is a step of immersing the object to be cleaned in the cleaning agent composition of the present disclosure. From the viewpoint of improving the removability of both discolored metal and flux residues, the immersion temperature is preferably 20°C or higher, more preferably 30°C or higher, still more preferably 40°C or higher, and from the viewpoints of handling safety and reduction of equipment load, it is preferably 80°C or lower, more preferably 70°C or lower, still more preferably 60°C or lower. From the same viewpoint, the immersion time is preferably 5 minutes or longer, more preferably 10 minutes or longer, still more preferably 30 minutes or longer, and preferably 3 hours or shorter, more preferably 2 hours or shorter, still more preferably 1 hour or shorter. In one or more embodiments, the cleaning method of the present disclosure preferably includes a step of rinsing with water and / or an alcohol such as methanol and drying after bringing the object to be cleaned into contact with the cleaning agent composition. From the point that the cleaning power of the cleaning agent composition of the present disclosure is easily exerted, it is preferable to irradiate ultrasonic waves when the cleaning agent composition of the present disclosure is in contact with the object to be cleaned, and it is more preferable that the ultrasonic waves are relatively strong.

[0044] In the cleaning process of the cleaning method of the present disclosure, in one or more other embodiments, it is a process (removal process) of cleaning and removing flux residues from the object to be cleaned with a flux residue remover. As the flux residue remover in the removal process, the flux residue cleaning and removing agent composition of the present disclosure described above can be mentioned. That is, the cleaning method of the present disclosure, in one or more embodiments, includes a process of cleaning and removing flux residues from the object to be cleaned with the flux cleaning and removing agent composition of the present disclosure, and the object to be cleaned is a substrate having flux residues that has undergone a process of heating to 200°C or higher (sintering process), and it is a flux residue cleaning and removing method.

[0045] [Method for manufacturing electronic components] In one aspect, the present disclosure relates to a method for manufacturing an electronic component (hereinafter, also referred to as "the method for manufacturing an electronic component of the present disclosure") using the cleaning method of the present disclosure. The method for manufacturing an electronic component of the present disclosure, in one or more embodiments, after applying a slurry containing flux between a substrate and a metal member or between two metal members on the substrate, includes a process of heating to 200°C or higher (sintering process) and a process of cleaning (cleaning process) the substrate (object to be cleaned) having flux residues that has undergone the sintering process using the cleaning agent composition or the cleaning method of the present disclosure. The cleaning process, in one or more embodiments, includes bringing the object to be cleaned having flux residues into contact with the cleaning agent composition of the present disclosure. As the cleaning method in the cleaning process, the same method as the cleaning method of the present disclosure described above can be mentioned. As the object to be cleaned, the object to be cleaned described above can be mentioned.

Examples

[0046] Hereinafter, the present disclosure will be specifically described by way of examples, but the present disclosure is not limited by these examples in any way.

[0047] 1. Preparation of cleaning agent composition (Examples 1 to 33, Comparative Examples 1 to 5) In a 100 mL glass beaker, each component was blended so as to have the compositions shown in Table 1-1, Table 1-2, and Table 2 below, and mixed under the following conditions to prepare the detergent compositions of Examples 1 to 33 and Comparative Examples 1 to 5. The numerical values of each component in the table indicate the content (mass %) in the prepared detergent composition, unless otherwise specified. <Mixing Conditions> Liquid temperature: 60 °C Stirrer: Magnetic stirrer (50 mm rotor) Rotation speed: 300 rpm Stirring time: 1 hour

[0048] The following are used as components of the detergent composition. (Component A) 2-Phenoxyethanol (PHG-S) [Ethylene glycol monophenyl ether, manufactured by Tokyo Chemical Industry Co., Ltd.] Benzyl alcohol [manufactured by Ranses Co., Ltd.] Butyl carbitol solvent (BDG) [Diethylene glycol monobutyl ether, manufactured by Nippon Emulsion Co., Ltd.] DBDG [Diethylene glycol dibutyl ether, manufactured by Nippon Emulsion Co., Ltd.] BFDG [Dipropylene glycol monobutyl ether, manufactured by Nippon Emulsion Co., Ltd.] Tetrahydrofurfuryl alcohol [manufactured by Fujifilm Wako Pure Chemical Corporation] (Component B) 2-Methylimidazole [manufactured by Tokyo Chemical Industry Co., Ltd.] 2-Ethyl-4-methylimidazole [manufactured by Fujifilm Wako Pure Chemical Corporation] 1-Methylimidazole [manufactured by Tokyo Chemical Industry Co., Ltd.] 1-Isobutyl-2-methylimidazole [manufactured by Tokyo Chemical Industry Co., Ltd.] (Component C) Caprylic acid [8 carbon atoms, manufactured by Kao] Capric acid [10 carbon atoms, manufactured by Kao] Dodecanedioic acid [12 carbon atoms, manufactured by Fujifilm Wako Pure Chemical Corporation] Lauric acid [12 carbon atoms, manufactured by Kao] Myristic acid [Carbon number 14, manufactured by Fujifilm Wako Pure Chemical Corporation] Palmitic acid [Carbon number 16, manufactured by Fujifilm Wako Pure Chemical Corporation] Oleic acid [Carbon number 18, manufactured by Fujifilm Wako Pure Chemical Corporation] Stearic acid [Carbon number 18, manufactured by Fujifilm Wako Pure Chemical Corporation] Behenic acid [Carbon number 22, manufactured by Kao Corporation] Lactic acid [Carbon number 2, manufactured by Fujifilm Wako Pure Chemical Corporation] Malonic acid [Carbon number 3, manufactured by Fujifilm Wako Pure Chemical Corporation] Malic acid [Carbon number 4, manufactured by Fujifilm Wako Pure Chemical Corporation] (Component D) Water [Pure water with a conductivity of 1 μS / cm or less produced by the pure water apparatus G-10DSTSET of Organo Corporation] (Component E) Diisopropanolamine [manufactured by Mitsui Chemicals Fine Chemicals Co., Ltd.] Dibutylaminoethanol [manufactured by Nippon Emulsion Co., Ltd.] (Inorganic acid) 2M sulfuric acid (17%) [manufactured by Fujifilm Wako Pure Chemical Corporation] * Diluted and adjusted with a reagent 35% hydrochloric acid (11.3M) [manufactured by Fujifilm Wako Pure Chemical Corporation] Note that the content of the inorganic acid in the table also includes the water content in the sulfuric acid or hydrochloric acid aqueous solution.

[0049] [Measurement of pH] The pH of the cleaning agent composition is the pH of the cleaning agent composition at 25°C. The value after 3 minutes of immersing the electrode of a pH meter (HM-30G, manufactured by Toa Denpa Kogyo Co., Ltd.) in the cleaning agent composition was measured.

[0050] 2. Evaluation of the cleaning agent composition [Evaluation of the oxidation film removal speed (removability of discolored metal)] Using the cleaning agent compositions of Examples 1 to 33 and Comparative Examples 1 to 5, the oxidation film removal speed (removability of discolored metal) was evaluated as follows. To 0.3 g of the Cu₂O reagent, 15 g of each cleaning agent composition (Examples 1 to 33, Comparative Examples 1 to 5) heated to 60 °C was added, and ultrasonic waves (38 kHz, output of 600 W) were irradiated for 6 minutes. This ultrasonic irradiation is a model simulating ultrasonic cleaning (cleaning time: 6 minutes) of the discolored metal (Cu₂O, oxide film). Thereafter, the cleaning agent composition was filtered through a 0.45 μm filter, and the amount of metal ions dissolved in the cleaning agent composition (amount of eluted copper ions, ppm) was determined by ICP measurement. Then, the removal speed of the oxide film was calculated by the following formula, and the results are shown in Table 1-1, Table 1-2, and Table 2. Removal speed of oxide film = Amount of eluted copper ions (ppm) / Cleaning time (minutes)

[0051] [Evaluation of damage to iron members] Using the cleaning agent compositions of Examples 1, 3, 4, 7 to 9, and Examples 31 to 33, the damage to the Fe members used in the apparatus and the substrate was evaluated as follows. To an SPCCB member (20 mm × 50 mm, steel plate specified in JIS G 3141), 50 g of each cleaning agent composition heated to 60 °C was added, and it was stored in a 60 °C constant temperature bath for 1 week. This is a model assuming damage to the members (here, Fe members) used in the apparatus and the substrate. After storing for 1 week, the cleaning agent composition was sampled, filtered through a 5 μm filter, and the amount of metal ions dissolved (amount of eluted iron ions, ppm) was determined by ICP measurement. The results are shown in Table 1-1 and Table 2. Note that Comparative Examples 1 to 5 were not evaluated for damage because the cleaning speed was slow.

[0052] [Evaluation of flux residue removability] The following cleaning test was performed using the following test substrate to evaluate the flux residue removability. [Test substrate] A test substrate was prepared by applying 0.05 g of abietic acid (flux) onto a 50 mm × 20 mm tough pitch copper plate and heating it on a hot plate at 250 °C for 1 hour. The abietic acid is in a state of adhering to a part of the copper plate surface. The test substrate produced here is a model that simulates the joining of metals on the substrate based on the heating temperature and holding time, and assumes a substrate with flux residues after the sintering process. <Washing Test> The test substrate was immersed in 100 g of each cleaning agent composition heated to 60 °C, and ultrasonic cleaning was performed for 15 minutes at an output of 38 kHz and 400 W. Then, the test substrate was pulled out from the cleaning agent composition, rinsed with water, dried with an air blow, and a substrate after cleaning was obtained. <Flux Residue Removal Rate> The appearance of the substrate before and after cleaning was observed, and the flux residue removal rate was calculated by the following formula. Flux residue removal rate (%) = Area where flux residue was removed after cleaning / Area where flux residue adhered before cleaning × 100 Area where flux residue was removed after cleaning = (Area where flux residue adhered before cleaning) - (Area where flux residue adhered after cleaning) It was confirmed that Examples 1 to 33 and Comparative Examples 1 to 5 all showed a flux residue removal rate close to 100%. Therefore, it can be evaluated that the cleaning agent compositions of Examples 1 to 33 and Comparative Examples 1 to 5 are excellent in flux residue removability.

[0053]

Table 1-1

[0054]

Table 1-2

[0055]

Table 2

[0056] As shown in Table 1-1, Table 1-2 and Table 2 above, the detergent compositions of Examples 1 to 33 were superior in removability of discolored metal (oxide film) compared to Comparative Examples 1 to 5. Incidentally, Examples 1 to 33 and Comparative Examples 1 to 5 were all excellent in removability of flux residues. In addition, the detergent compositions of Examples 1, 3, 4, 7 to 9 using carboxylic acids having 8 or more carbon atoms as Component C were found to have reduced damage to iron members compared to Examples 31 to 33 using carboxylic acids having 2 to 4 carbon atoms as Component C. It is also considered that the damage to the iron members is reduced for the detergent compositions of Examples 2, 5, and 6.

Industrial Applicability

[0057] By using the detergent composition of the present disclosure, both discolored metal and flux residues can be efficiently removed. Therefore, for example, it becomes possible to shorten the flux cleaning process in the manufacturing process of semiconductor devices and improve the performance and reliability of the manufactured semiconductor devices, thereby improving the productivity of semiconductor devices.

Claims

1. A cleaning agent composition for removing flux residues, comprising at least one organic solvent (Component A) selected from a compound represented by the following formula (I) and a compound represented by the following formula (II), an imidazole compound (Component B) represented by the following formula (III), a carboxylic acid (Component C), and water (Component D). R 1 -O-(AO) n -R 2 (I) In the above formula (I), R 1 is a phenyl group or an alkyl group having 1 to 8 carbon atoms, R 2 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, AO is an ethylene oxide group or a propylene oxide group, n is the number of moles of AO added, and is an integer of 1 or more and 3 or less. R 3 -CH 2 OH (II) In the above formula (II), R 3 is a phenyl group, a benzyl group, a cyclohexyl group, a furyl group, a tetrahydrofuryl group, a furfuryl group or a tetrahydrofurfuryl group. 【Chemical 1】 In formula (III), R 4 , R 5 , R 6 and R 7 each independently represents a hydrogen atom, a halogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a phenyl group, an aldehyde group, a carboxy group, an aminoethyl group, an aminopropyl group, an acetyl group, a hydroxyethyl group or a hydroxypropyl group.

2. The cleaning agent composition for removing flux residues according to Claim 1, wherein the content of Component A is 10% by mass or more and 90% by mass or less.

3. The cleaning agent composition for removing flux residues according to Claim 1 or 2, wherein the content of Component B is 0.5% by mass or more and 15% by mass or less.

4. Component B is at least one selected from imidazole, 1-methylimidazole, 1-ethylimidazole, 1-propylimidazole, 1-isopropylimidazole, 1-acetylimidazole, 1-aminopropylimidazole, 1-hydroxyethylimidazole, 2-methylimidazole, 2-ethylimidazole, 2-propylimidazole, 2-isopropylimidazole, 2-acetylimidazole, 2-aminopropylimidazole, 2-hydroxyethylimidazole, 4-methylimidazole, 4-ethylimidazole, 4-propylimidazole, 4-isopropylimidazole, 4-acetylimidazole, 4-aminopropylimidazole, 4-hydroxyethylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, and 2-ethyl-4-methylimidazole. The cleaning agent composition for removing flux residues according to Claim 1 or 2.

5. The cleaning agent composition for removing flux residues according to Claim 1 or 2, wherein the content of Component C is 0.5% by mass or more and 10% by mass or less.

6. The cleaning agent composition for removing flux residues according to Claim 1 or 2, wherein the mass ratio (C / A) of Component C to Component A is 0.0001 or more.

7. The cleaning agent composition for removing flux residues according to Claim 1 or 2, wherein the mass ratio (B / A) of Component B to Component A is 0.005 or more and 1.0 or less.

8. The cleaning agent composition for removing flux residues according to Claim 1 or 2, wherein the mass ratio (B / C) of Component B to Component C is 0.01 or more and 25 or less.

9. The cleaning agent composition for removing flux residues according to Claim 1 or 2, wherein the content of Component D is 0.5% by mass or more and 20% by mass or less.

10. The cleaning agent composition for removing flux residues according to claim 1 or 2, wherein component C is a carboxylic acid having 8 or more carbon atoms.

11. A cleaning method comprising a cleaning step of cleaning an object to be cleaned having flux residues with the cleaning agent composition for removing flux residues according to claim 1 or 2, wherein the object to be cleaned is a substrate that has been subjected to a step of heating to 200°C or higher.

12. The cleaning method according to claim 11, wherein the object to be cleaned has a metal member containing copper on the substrate.

13. The cleaning method according to claim 12, wherein the substrate surface and / or the metal member of the object to be cleaned includes a portion where the metal is oxidized.

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