KR20220103198A - Flux composition and solder paste using same - Google Patents

Abstract

The flux composition of the present invention comprises 3-methyl-1,3-butanediol and an active agent.

Description

Flux composition and solder paste using same

The present invention relates to a flux composition and a solder paste using the same.

Up to now, various developments have been made on fluxes for soldering. As a technique of this kind, the technique described in patent document 1 is known, for example. Patent Document 1 describes a flux composition containing isobornylcyclohexanol as a solvent (Claim 1 of Patent Document 1).

Patent Document 1: Japanese Patent Application Laid-Open No. 2015-160244

However, as a result of the inventor's examination, it was found that, in the flux composition described in Patent Document 1, there is room for improvement in terms of low residual properties during rapid heating. In addition, in the flux composition, the retainability of the solder ball is required.

The present inventors further investigated, and found the following.

In a solder bonding process according to a fast reflow of a temperature increase rate, TCB (thermocompression bonding), or the like, a higher level of low residue than in the prior art is required.

As a conventional low-residue flux solvent, isobornylcyclohexanol is sometimes used.

However, since isobornylcyclohexanol is a high-viscosity solvent, it has excellent retainability of solder balls, but since it is also a high-boiling solvent, there is room for improvement in the residue at the time of rapid heating.

On the other hand, as a solvent with a relatively lower boiling point than isobornyl cyclohexanol, hexyl diglycol etc. are known, for example.

However, although hexyl diglycol has a relatively low boiling point, since it is also a low-viscosity solvent, the retainability of the solder balls is lowered, and there is a fear that defects such as ball missing are generated in the solder bonding process.

The present inventors studied the above technical relationship between the boiling point and the viscosity, paying attention to the characteristics of the solvent, and studied diligently. It found that it was possible to improve both the low residue properties and the retainability of the solder balls, thereby completing the present invention.

According to the present invention,

A flux composition is provided comprising 3-methyl-1,3-butanediol, and an active agent.

In addition, according to the present invention,

A solder paste comprising the above flux composition and metal powder is provided.

ADVANTAGE OF THE INVENTION According to this invention, the flux composition excellent in the low residual property at the time of rapid heating, and the retainability of a solder ball, and the solder paste using the same are provided.

An outline of the flux composition of the present embodiment will be described.

The flux composition comprises 3-methyl-1,3-butanediol, and an active agent.

This flux composition is used in a solder bonding process for bonding solder and a metal to be joined.

According to the knowledge of the present inventors, the following were discovered.

Usually, in the reflow process at the time of solder bonding, the temperature increase rate of about 1-2 degreeC/sec is employ|adopted. For example, in FIG. 1 of Patent Document 1, the relationship between the reflow temperature and time is described, therein, there is a condition in which the temperature of 180°C to 240°C is raised to about 40 sec, that is, a temperature increase rate of about 1.5°C/sec. Reflow is shown.

However, in a reflow process of rapid heating or a solder bonding process such as TCB (thermocompression bonding), the temperature rise rate is higher than usual, and therefore, the flux composition is required to have a low residual property at a higher level than before.

As a conventional low-residue flux solvent, isobornylcyclohexanol or hexyl diglycol may be used.

Since isobornylcyclohexanol is a high-viscosity solvent, it has excellent retainability of solder balls, but since it is also a high-boiling solvent, there is room for improvement in the residue at the time of rapid heating. On the other hand, although hexyl diglycol has a relatively low boiling point, since it is also a low-viscosity solvent, the retainability of the solder balls is lowered, and there is a fear that defects such as ball missing are generated in the solder bonding process.

Based on the technical relationship between the boiling point and the viscosity, the following research was intensively conducted, paying attention to the characteristics of the solvent. It has been found that both the four properties and the retainability of the solder ball can be improved.

Although the detailed mechanism is not clear, the use of 3-methyl-1,3-butanediol as a solvent having an appropriate boiling point and viscosity improves the flux composition's low residue during rapid heating and solder ball retention. You might think you can do it.

The flux composition of the present embodiment can be used in a solder bonding process in which the lower limit of the temperature increase rate is, for example, 3°C/sec or more, preferably 4°C/sec or more, and more preferably 5°C/sec or more. Although the upper limit of a temperature increase rate is not specifically limited, According to an actual process, it can set suitably.

According to the present embodiment, a flux composition with a low residue can be realized even in the reflow process and the TCB process with such a relatively high rate of temperature increase.

Generally, there are known a cleaning application that requires cleaning of residues after brazing, and a no-cleaning application that can be used without cleaning after brazing.

Although the flux composition of the present embodiment can be applied to any application, it can be used as a flux composition for no-clean use, and more preferably as a flux composition for no-clean use in a solder bonding process with a high temperature increase rate.

In addition, the upper limit of the residual amount of the flux composition as measured by the following procedure is, for example, 10% by weight or less, preferably 8% by weight or less, more preferably less than 5% by weight. Thereby, the low residual property at the time of rapid heating can be improved further. The lower limit of the residual amount is not particularly limited.

(procedure)

When the flux composition was heat-treated from 25°C to 250°C in a nitrogen atmosphere at a temperature increase rate of 5°C/sec, the weight W0 before heating and the weight W1 after heating were measured, and the obtained W0 and W1 were used. , from the formula: W1/W0Х100%, the amount of residue (% by weight) is calculated.

By including 3-methyl-1,3-butanediol, the flux composition maintains its low residue even when it contains one or two or more selected from the group consisting of an activator, another solvent, a base resin, and an additive. it is possible

The lower limit of the viscosity of the flux composition at 25°C, measured in accordance with JIS Z 3284-3:2014, may be, for example, 500 mPa·s or more. Thereby, it is possible to improve the retainability of the solder ball. The upper limit of the viscosity of the flux composition at 25°C is not particularly limited, but may be, for example, 5,000 mPa·s or less.

In the present embodiment, it is possible to control the residual amount and viscosity by appropriately selecting the type and compounding amount of each component contained in the flux composition, a method for preparing the flux composition, and the like, for example. Among these, for example, the content ratio of 3-methyl-1,3-butanediol and other components, the solvent using 3-methyl-1,3-butanediol alone, or 3-methyl-1,3- In the mixed solvent of butanediol and other solvent, the type and content ratio of the other solvent are appropriately adjusted, and the fatty acid amide serving as the thixotropic agent is substantially not included, etc. It can be mentioned as an element for making

Hereinafter, each component of the flux composition of the present embodiment will be described in detail.

(activator)

The flux composition may contain an activator having a property of removing metal oxides.

By including the activator, it is possible to increase the solder wettability during the solder bonding process.

In general, the solder bonding process is carried out in a reducing gas atmosphere such as formic acid gas, or in an inert gas atmosphere containing nitrogen gas or argon gas, etc. which does not contain a reducing gas substantially or under a reduced pressure atmosphere. In this case, it is known that it is carried out under an atmospheric pressure environment.

The flux composition containing the activator can be used in a solder bonding process in an inert gas atmosphere or a reduced pressure atmosphere substantially free of reducing gas.

Specific examples of the activator include organic acids, amines, halogen activators, phosphorus activators, and the like. These may be used independently or may be used in combination of 2 or more type.

Although the detailed mechanism of these activators is not certain, it is thought that the metal oxide film on the surface of the metal to be soldered and soldered can be removed by forming a salt or chelate with the metal oxide.

The upper limit of the content of the active agent in the flux composition may be, for example, 30 wt% or less or 20 wt% or less. The lower limit of the content of the active agent in the flux composition is not particularly limited, but may be 0.1 wt% or more or 1 wt% or more.

In addition, in this specification, "-" represents that an upper limit and a lower limit are included unless otherwise indicated.

Examples of the organic acid include monocarboxylic acids, dicarboxylic acids, anhydrides of dicarboxylic acids, and oxy acids. These may be used independently or may be used in combination of 2 or more type. Among these, you may use the polyhydric organic acid which has two or more of at least one of a hydroxyl group and a carboxy group in a molecule|numerator.

As an example of a specific example of an organic acid, For example, glutaric acid, adipic acid, azeraic acid, eicosic acid diacid, citric acid, glycolic acid, succinic acid, salicylic acid, diglycolic acid, dipicolinic acid, dibutylaniline diglycolic acid, water Beric acid, sebacic acid, thioglycolic acid, terephthalic acid, dodecane diacid, parahydroxyphenyl acetic acid, picolinic acid, phenyl succinic acid, phthalic acid, fumaric acid, maleic acid, malonic acid, lauric acid, benzoic acid, tartaric acid, isocyanuric acid Tris(2-carboxyethyl), glycine, 1,3-cyclohexane dicarboxylic acid, 2,2-bis(hydroxymethyl) propionic acid, 2,2-bis(hydroxymethyl) butanoic acid, 2,3-dihydr and hydroxybenzoic acid, 2,4-diethylglutaric acid, 2-quinoline carboxylic acid, 3-hydroxybenzoic acid, malic acid, p-anisic acid, stearic acid, 12-hydroxystearic acid, oleic acid, linoleic acid, and linolenic acid.

Among these, from the viewpoint of low residue, the organic acid may include an organic acid having 11 or less carbon atoms.

Examples of the organic acid having 11 or less carbon atoms include glycolic acid (2 carbon atoms), thioglycolic acid (2 carbon atoms), glycine (2 carbon atoms), malonic acid (3 carbon atoms), fmalic acid (4 carbon atoms), maleic acid (4 carbon atoms). ), succinic acid (4 carbon atoms), diglycolic acid (4 carbon atoms), tartaric acid (4 carbon atoms), malic acid (4 carbon atoms), glutaric acid (5 carbon atoms), 2,2-bis(hydroxymethyl) propionic acid (5 carbon atoms) ), adipic acid (6 carbon atoms), citric acid (6 carbon atoms), picolinic acid (6 carbon atoms), benzoic acid (7 carbon atoms), 2,2-bis(hydroxymethyl) butanoic acid (6 carbon atoms), salicylic acid (7 carbon atoms) ), dipicolinic acid (7 carbon atoms), 2,3-dihydroxybenzoic acid (7 carbon atoms), 3-hydroxybenzoic acid (7 carbon atoms), suberic acid (8 carbon atoms), phthalic acid (8 carbon atoms), isophthalic acid ( 8 carbon atoms), terephthalic acid (8 carbon atoms), parahydroxyphenyl acetic acid (8 carbon atoms), 1,3-cyclohexane dicarboxylic acid (8 carbon atoms), p-anisic acid (8 carbon atoms), azeranic acid (9 carbon atoms), 2 ,4-diethylglutaric acid (9 carbon atoms), sebacic acid (10 carbon atoms), phenyl succinic acid (10 carbon atoms), 2-quinoline carboxylic acid (10 carbon atoms), 4-tert-butyl benzoic acid (11 carbon atoms), etc. have.

Moreover, as an organic acid, the hydrogenated dimeric acid which is the hydrogenated product which added hydrogen to dimeric acid, trimeric acid, and dimeric acid, and the hydrogenated trimeric acid which are the hydrogenated products which added hydrogen to trimer acid are mentioned, for example.

The content of the organic acid in the flux composition may be, for example, 0 to 15% by weight or 1 to 10% by weight.

Examples of the amines include monoethanolamine, diphenylguanidine, ethylamine, triethylamine, ethylenediamine, triethylenetetramine, 2-methylimidazole, 2-undecylimidazole, and 2-heptadecyl. Midazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole Sol, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl- 4-Methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium tri Mellitate, 2,4-diamino-6-[2'-methylimidazolyl(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimida Zolyl(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl(1')]-ethyl-s-triazine, 2 ,4-diamino-6-[2'-methylimidazolyl(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl- 4,5-dihydroxymethyl imidazole, 2-phenyl-4-methyl-5-hydroxymethyl imidazole, 2,3-dihydro-1H-pyrroro[1,2-a]benzimidazole, 1 -Dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazole, 2-phenylimidazole, 2,4-diamino-6-vinyl-s-triazine, 2,4- Diamino-6-vinyl-s-triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-s-triazine, epoxy-imidazole adduct, 2-methylbenzoimi Dazole, 2-octylbenzoimidazole, 2-pentylbenzoimidazole, 2-(1-ethylpentyl)benzoimidazole, 2-nonylbenzoimidazole, 2-(4-thiazolyl)benzoimidazole, benzimidazole , 2-(2'-hydroxy-5'-methylphenyl) benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2- (2'-hydroxyl-3',5'-di-tert-amylphenyl) benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2'- methylene bis[6-(2H-benzot) Riazol-2-yl)-4-tert-octylphenol], 6-(2-benzotriazolyl)-4-tert-octyl-6′-tert-butyl-4′-methyl-2,2′-methylene Bisphenol, 1,2,3-benzotriazole, 1-[N,N-bis(2-ethylhexyl) aminomethyl]benzotriazole, carboxybenzotriazole, 1-[N,N-bis(2-ethyl) Hexyl) aminomethyl]methylbenzotriazole, 2,2′-[[(methyl-1H-benzotriazol-1-yl)methyl]imino]bis ethanol, 1-(1′,2′-dicarboxyethyl ) benzotriazole, 1-(2,3-dicarboxypropyl) benzotriazole, 1-[(2-ethylhexylamino) methyl] benzotriazole, 2,6-bis[(1H-benzotriazole-1 -yl) methyl]-4-methylphenol, 5-methylbenzotriazole, 5-phenyltetrazole, etc. are mentioned.

The upper limit of the content of the amines in the flux composition may be, for example, 15 wt% or less or 10 wt%. The lower limit of the content of the amines in the flux composition is not particularly limited, but may be 0.1 wt% or more or 1 wt% or more.

Examples of the halogen-based activator include organic halogen compounds and amine hydrohalic acid salts.

Examples of the organic halogen compound include trans-2,3-dibromo-1,4-butenediol, triaryl isocyanurate 6 bromide, 1-bromo-2-butanol, 1-bromo- 2-propanol, 3-bromo-1-propanol, 3-bromo-1,2-propanediol, 1,4-dibromo-2-butanol, 1,3-dibromo-2-propanol, 2 and 3-dibromo-1-propanol, 2,3-dibromo-1,4-butanediol, and 2,3-dibromo-2-butene-1,4-diol.

Examples of other organic halogen compounds include chloroalkane which are organic chloro compounds, chlorinated fatty acid esters, hetic acid, and hetic anhydride. Further, fluorine-based surfactants which are organic fluorine compounds, surfactants having a perfluoroalkyl group, polytetrafluoroethylene, and the like can be mentioned.

Examples of the amine hydrohalides include hydrohalic acids such as hydroiodic acid (HI), hydrobromic acid (HBr), hydrochloric acid (HCl) and hydrofluoric acid (HF), aniline, diphenylguanidine, diethylamine, The salt which combined amine compounds, such as isopropylamine, is mentioned. Moreover, as an amine hydrohalic acid salt equivalent, the salt which combined tetrafluoroboric acid (HBF ₄ ) and an amine compound can also be used.

The upper limit of the content of the halogen-based active agent in the flux composition may be, for example, 10 wt% or less or 5 wt% or less. The lower limit of the content of the halogen-based active agent in the flux composition is not particularly limited, but may be 0.1 wt% or more or 1 wt% or more.

The content of the organic halogen compound in the flux composition may be, for example, 0 to 5% by weight.

The content of the amine hydrohalide in the flux composition may be, for example, 0-1 wt%.

Examples of the phosphorus-based activator include phosphonic acid esters, phenyl-substituted phosphinic acid phosphonic acids, and phosphoric acid esters.

As the phosphonic acid ester, for example, 2-ethylhexyl (2-ethylhexyl) phosphonate, n-octyl (n-octyl) phosphonate, n-decyl (n-decyl) phosphonate, and n- butyl (n-butyl) phosphonate.

Examples of the phenyl-substituted phosphinic acid include phenylphosphinic acid and diphenylphosphinic acid.

The upper limit of the content of the phosphorus-based active agent in the flux composition may be, for example, 10 wt% or less or 5 wt% or less. The lower limit of the content of the phosphorus-based active agent in the flux composition is not particularly limited, but may be 0.1 wt% or more or 1 wt% or more.

(solvent)

The flux composition contains a solvent.

The flux composition contains, as a solvent, at least 3-methyl-1,3-butanediol.

As the solvent in the flux composition, a single solvent of 3-methyl-1,3-butanediol may be used, or a mixed solvent containing another solvent other than 3-methyl-1,3-butanediol may be used.

As another solvent, there exist a solid solvent and a liquid solvent, for example. These may be used independently or may be used in combination of 2 or more type.

An example of the lower limit of the content of 3-methyl-1,3-butanediol is, for example, 10% by weight or more, 20% by weight or more, or 30% by weight or more in 100% by weight of the flux composition. Thereby, the low residual property at the time of rapid heating and the holding|maintenance of a solder ball can be improved. An example of the lower limit of the content of 3-methyl-1,3-butanediol may be, for example, 90% by weight or more. Thereby, even when the upper limit of the bonding temperature in a solder bonding process is comparatively low, the low residual property at the time of rapid heating can be improved.

Although the upper limit of content of 3-methyl-1, 3- butanediol is not specifically limited, 100 weight% or less may be sufficient, and 99 weight% or less may be sufficient.

The flux composition may further contain a solid solvent. That is, the flux composition may contain a mixed solvent of 3-methyl-1,3-butanediol and a solid solvent.

The solid solvent may be a solid solvent at 25°C, and the lower limit of the melting point may be, for example, 30°C or higher, 40°C or higher, or 50°C or higher. The upper limit of melting|fusing point is good also as 280 degrees C or less, for example.

As a solid solvent, an alcohol type solid solvent, a phenol type solid solvent, etc. are used, for example.

These may be used independently or may be used in combination of 2 or more type.

The alcohol-based solid solvent should just be a solid solvent which has one or two or more hydroxyl groups in a molecule|numerator, and the polyhydric-alcohol-type solid solvent which has two or more than three hydroxyl groups is preferable.

Specific examples of the polyhydric alcohol-based solid solvent include pentaerythritol, trimethylolpropane, 2,5-dimethyl-2,5-hexanediol, and neopentyl glycol.

A phenolic solid solvent may just be a solid solvent which has 1 or 2 or more phenol groups in a molecule|numerator, and 1 or 2 or more hydroxyl groups may couple|bond with the benzene ring of a phenol group.

The content of the solid solvent in the flux composition may be, for example, 0 to 40% by weight or 1 to 30% by weight.

The flux composition may further contain a liquid solvent that is liquid at 25°C other than 3-methyl-1,3-butanediol.

As the liquid solvent, an alcohol-based solvent, a glycol ether-based solvent, terpineols, hydrocarbons, esters, water, and the like are used. These may be used independently or may be used in combination of 2 or more type. Among these, as the liquid solvent, at least one of an alcohol-based solvent and a glycol ether-based solvent may be used.

The content of the liquid solvent in the flux composition may be, for example, 0 to 50% by weight or 1 to 45% by weight.

Examples of the alcohol-based solvent include isopropyl alcohol, 1,2-butanediol, isobornylcyclohexanol, 2,4-diethyl-1,5-pentanediol, and 2,2-dimethyl-1,3-propane. Diol, 2,5-dimethyl-2,5-hexanediol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,3-dimethyl-2,3-butanediol, 1,1,1-tris (hydroxymethyl) ethane, 2-ethyl-2-hydroxymethyl-1,3-propanediol, 2,2'-oxy bis (methylene) bis (2-ethyl-1,3-propanediol), 2, 2-bis(hydroxymethyl)-1,3-propanediol, 1,2,6-trihydroxyhexane, bis[2,2,2-tris(hydroxymethyl)ethyl]ether, 1-ethynyl- 1-Cyclohexanol, 1,4-cyclohexanediol, 1,4-cyclohexane dimethanol, erythritol, threitol, guaiacol glycerol ether, 3,6-dimethyl-4-octyne-3,6-diol , 2,4,7,9-tetramethyl-5-decyne-4,7-diol, and the like.

Examples of the glycol ether solvent include hexyldiglycol, diethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, 2-methylpentane-2,4-diol, diethylene glycol monohexyl ether, di Ethylene glycol dibutyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, etc. are mentioned.

(Base resin)

The flux composition may also contain a base resin.

Examples of the base resin include rosin-based resins, (meth)acrylic resins, urethane-based resins, polyester-based resins, phenoxy resins, vinyl ether-based resins, terpene resins, and modified terpene resins (eg, aromatic modified terpene resins). , hydrogenated terpene resin, hydrogenated aromatic modified terpene resin, etc.), terpene phenol resin, modified terpene phenol resin (eg, hydrogenated terpene phenol resin, etc.), styrene resin, modified styrene resin (eg, styrene acrylic resin, styrene maleate) phosphorus resin, etc.), xylene resin, modified xylene resin (for example, phenol-modified xylene resin, alkylphenol-modified xylene resin, phenol-modified resor-type xylene resin, polyol-modified xylene resin, polyoxyethylene-added xylene resin, etc.) can These may be used independently or may be used in combination of 2 or more type.

In addition, in this specification, "(meth)acrylic-type resin" means the concept containing a methacryl-type resin and an acrylic resin.

Among these, base resin may also contain rosin-type resin.

Examples of the rosin-based resin include raw material rosin such as gum rosin, wood rosin, and tall oil rosin, and derivatives obtained from raw material rosin. As the derivative, for example, purified rosin, hydrogenated rosin, disproportionated rosin, polymerized rosin, and α,β unsaturated carboxylic acid-modified products (acrylated rosin), maleinized rosin, promalated rosin, etc.), and purified products of polymerized rosin, water Digested substances and disproportionated substances, purified substances of α,β unsaturated carboxylic acid-modified substances, hydrides, disproportionation substances, and the like are exemplified. These rosin-type resins are used individually by 1 type or in combination of 2 or more type.

The content of the base resin in the flux composition may be, for example, 0 to 10% by weight or 1 to 5% by weight.

(additive)

The flux composition may contain additives normally added to the flux as long as the effects of the present invention are not impaired.

As an additive, a thixotropic agent, antioxidant, a waterproofing agent, an antifoamer, a chlorine agent, surfactant, a coloring agent, etc. are mentioned, for example. These may be used independently or may be used in combination of 2 or more type.

Examples of the thixotropic agent include wax-based thixotropic agents such as hydrogenated castor oil, carnauba wax, and beeswax.

As antioxidant, a hindered phenol-type antioxidant, phosphorus antioxidant, etc. are mentioned.

Among these, the flux composition may be constituted so as to contain substantially no fatty acid amide as a thixotropic agent. Thereby, the low residual property at the time of rapid heating can be improved.

The flux composition of the present embodiment can be mixed with metal powder and used as a solder paste, or can be used as a flux for ball attachment or tip attachment.

The solder paste of this embodiment contains the flux composition and the metal powder.

Metal powder is Sn alone, Sn-Ag-based, Sn-Cu-based, Sn-Ag-Cu-based, Sn-Bi-based, Sn-In-based or the like, or Pb, Sb, It may be composed of a solder powder to which Bi, In, Cu, Zn, As, Ag, Cd, Fe, Ni, Co, Au, Ge, P or the like is added.

The solder alloy includes at least one of As: 25 to 300 ppm by weight, and Sb: greater than 0 ppm by weight and up to 3000 ppm by weight, Bi: greater than 0 ppm by weight and less than or equal to 10000 ppm by weight, and Pb: greater than 0 ppm by weight and less than or equal to 5100 ppm by weight. , and the balance preferably has an alloy composition composed of Sn. The solder alloy may further contain at least one of Ag: 0-4 wt% and Cu: 0-0.9 wt%.

The content of the metal powder and the flux composition in the solder paste is not limited, and the content of the metal powder and the flux can be, for example, 5 to 95% by weight and 5 to 95% by weight of the flux.

There is no limitation on the method for producing the flux composition and the solder paste, and it can be produced by mixing the raw materials simultaneously or sequentially by any method.

For the preparation of the flux composition, all the components of the flux composition may be finally mixed, the other components may be sequentially mixed with the solvent, the mixture of the other components may be added to the solvent, or the solvent and all other components may be mixed simultaneously. .

In addition, in the preparation of the solder paste, it is not necessarily necessary to prepare a flux composition in advance and mix it with the metal powder. Finally, all components of the flux composition, the metal powder, and an additive to be added to the solder paste as needed are mixed. As long as it is a mixture, it is possible to mix a part of the components of the flux composition with the metal powder, and then add the remaining components of the flux composition.

The flux composition and solder paste of the present embodiment can be used, for example, in a method for manufacturing a semiconductor device.

A method for manufacturing a semiconductor device includes a step of applying a flux composition or solder paste to an electrode, placing a solder ball on the electrode, for example, heat-treating a substrate such as a lead frame or a printed wiring board and a semiconductor element, You may also include the process of joining these through the molten solder ball.

The heat treatment may be performed under a nitrogen atmosphere or a reduced pressure atmosphere, and the temperature increase rate may be performed under conditions of, for example, 3°C/sec or more.

The manufacturing method of a semiconductor device may be comprised so that the process of washing|cleaning a flux composition or a solder paste may not be included after the process of joining.

As mentioned above, although embodiment of this invention was mentioned, these are illustrations of this invention, and various structures other than the above can be employ|adopted. In addition, this invention is not limited to the above-mentioned embodiment, The deformation|transformation, improvement, etc. within the range which can achieve the objective of this invention are included in this invention.

Hereinafter, examples of reference forms are given.

1. A flux composition comprising an active agent, comprising:

3-methyl-1,3-butanediol;

The residual amount of the flux composition, as measured by the following procedure, is less than 10% by weight;

The viscosity of the flux composition at 25°C measured in accordance with JIS Z 3284-3: 2014 is 500 mPa·s or more;

flux composition.

(procedure)

When the flux composition was heat-treated from 25°C to 250°C in a nitrogen atmosphere at a temperature increase rate of 5°C/sec, the weight W0 before heating and the weight W1 after heating were measured, and the obtained W0 and W1 were used. , from the formula: W1/W0Х100%, the amount of residue (% by weight) is calculated.

2. The flux composition according to 1., wherein

A flux composition for use in a solder bonding process having a temperature increase rate of 3°C/sec or more.

3. The flux composition according to 1. or 2., wherein

The flux composition, wherein the activator comprises one or two or more selected from the group consisting of organic acids, amines, halogen activators, and phosphorus activators.

4. The flux composition according to any one of 1.3 to 1.

The flux composition, wherein the activator comprises an organic acid having 11 or less carbon atoms.

5. The flux composition according to any one of 1. to 4.

A flux composition used in a solder bonding process in an inert gas atmosphere or a reduced pressure atmosphere substantially free of reducing gas.

6. The flux composition according to any one of 1. to 5.

A flux composition substantially free of fatty acid amides.

7. The flux composition according to any one of 1. to 6.

The flux composition, wherein the content of 3-methyl-1,3-butanediol is 10% by weight or more in 100% by weight of the flux composition.

8. The flux composition according to any one of 1. to 7.

The flux composition, wherein the content of 3-methyl-1,3-butanediol is 90% by weight or more in 100% by weight of the flux composition.

9. The flux composition according to any one of 1. to 8.

A flux composition comprising a solid solvent.

10. The flux composition according to any one of 1. to 9.

A flux composition comprising a liquid solvent other than 3-methyl-1,3-butanediol.

11. The flux composition according to any one of 1. to 10.

A flux composition comprising a base resin.

12. The flux composition according to any one of 1. to 11.

A flux composition for no-clean use.

13. A solder paste comprising the flux composition according to any one of 1. to 12 and a metal powder.

Hereinafter, additional examples of reference forms are appended.

1. A flux composition comprising 3-methyl-1,3-butanediol.

2. The flux composition according to 1., wherein

The flux composition, wherein the residual amount of the flux composition measured by the following procedure is 10% by weight or less.

(procedure)

When the flux composition was heat-treated from 25°C to 250°C in a nitrogen atmosphere at a temperature increase rate of 5°C/sec, the weight W0 before heating and the weight W1 after heating were measured, and the obtained W0 and W1 were used. , from the formula: W1/W0Х100%, the amount of residue (% by weight) is calculated.

3. The flux composition according to 1. or 2.

A flux composition for use in a solder bonding process having a temperature increase rate of 3°C/sec or more.

4. The flux composition according to any one of 1.3 to 1.

A flux composition comprising an active agent.

5. A flux composition as described in 4.

The flux composition, wherein the activator comprises one or two or more selected from the group consisting of organic acids, amines, halogen activators, and phosphorus activators.

6. The flux composition according to 4. or 5.

The flux composition, wherein the activator comprises an organic acid having 11 or less carbon atoms.

7. The flux composition according to any one of 4. to 6.

A flux composition used in a solder bonding process in an inert gas atmosphere or a reduced pressure atmosphere substantially free of reducing gas.

8. The flux composition according to any one of 1. to 7.

A flux composition substantially free of fatty acid amides.

9. The flux composition according to any one of 1. to 8.

The flux composition, wherein the content of 3-methyl-1,3-butanediol is 10% by weight or more in 100% by weight of the flux composition.

10. The flux composition according to any one of 1. to 9.

The flux composition, wherein the content of 3-methyl-1,3-butanediol is 90% by weight or more in 100% by weight of the flux composition.

The flux composition according to any one of 11.1. to 10., comprising:

A flux composition comprising a solid solvent.

12. The flux composition according to any one of 1. to 11.

A flux composition comprising a liquid solvent other than 3-methyl-1,3-butanediol.

13. The flux composition according to any one of 1. to 12.

A flux composition comprising a base resin.

14. The flux composition according to any one of 1. to 13.

A flux composition for no-clean use.

15. The flux composition according to any one of 1. to 14.

A flux composition, wherein the flux composition has a viscosity of 500 mPa·s or more at 25°C, measured in accordance with JIS Z 3284-3: 2014.

16. A solder paste comprising the flux composition according to any one of 1. to 15 and a metal powder.

[Example]

Hereinafter, although this invention is demonstrated in detail with reference to an Example, this invention is not limited at all by description of these Examples.

Hereinafter, the information of the raw material component in Table 1 is shown.

(solvent)

·3-Methyl-1,3-butanediol (liquid at 25°C, boiling point: 203°C, viscosity at 25°C: 250 mPa·s)

·Solid solvent 1: pentaerythritol (25°C solid, melting point: 260°C)

·Solid solvent 2: trimethylolpropane (25°C solid, melting point: 58°C)

·Liquid solvent 1: isobornylcyclohexanol (liquid at 25°C, boiling point: 318°C, viscosity at 25°C: 89,000 mPa·s)

·Liquid solvent 2: Hexyldiglycol (liquid at 25°C, boiling point: 258°C, viscosity at 25°C: 8.6 mPa·s)

(activator)

·Organic acid 1: succinic acid

·Organic acid 2: diglycolic acid

·Organic acid 3: glutaric acid

·Amines 1: monoethanolamine

·Organic halogen compounds 1: trans-dibromobutenediol

·Amine hydrohalides 1: diphenylguanidine HBr salt

(additive)

Aliphatic amide 1: Polyamide

(Base resin)

·Rosin-based resin 1: hydrogenated rosin

<Preparation of flux composition>

A flux composition was obtained by mixing the raw material components in the mixing ratio shown in Table 1 below.

The obtained flux composition was evaluated for the following evaluation items.

<Viscosity>

About the obtained flux composition, the viscosity in 25 degreeC was measured based on JIS　Z　3284-3:2014. As a result, Examples 1-15 showed 500 mPa*s or more, and Comparative Example 1 showed less than 500 mPa*s.

<Low residue>

As a test evaluation method according to the TG method (thermogravimetry), an aluminum pan is filled with 10 mg of the flux composition of each Example and each comparative example, and TGD9600 manufactured by ULVAC is used, under a nitrogen atmosphere, from 25°C to 250°C, It heated at the temperature increase rate of 5 degreeC/sec.

The weight W0 of each flux composition before heating and the weight W1 of each flux composition after heating were measured. Using the obtained W0 and W1, the residual amount ΔW (wt%) was obtained from the formula: W1/W0Х100%.

The residual amount ΔW was evaluated as 000 when it was less than 3% by weight, 00 when it was 3% by weight or more and less than 5% by weight, ○ when it was 5% by weight or more and less than 10% by weight, and Х when it was 10% by weight or more. A result is shown in Table 1.

<Solder Ball Retention>

On the printed circuit board provided with the copper (Cu-OSP) electrode by which the preflux process was carried out, 30 pieces (N=30) of SRO (solder resist opening diameter) of (phi) 0.24 mm were formed, and the sample was prepared.

Next, the flux composition of each Example and each comparative example was spray-coated with respect to the copper electrode in soldering resist opening.

Then, on the copper electrode in the opening, each φ0.3 mm solder ball (SAC305: Sn-3Ag-0.5Cu) is mounted, and in a nitrogen atmosphere, from 25°C to 250°C, at a temperature increase rate of 5°C/sec. It heated and heated at 250 degreeC for 30 sec. Then, in N ₂ reflow, it cooled to 25 degreeC. After reflow, the state of the copper electrode was confirmed.

The case where the number of solder balls separated from the copper electrode was 0 out of 30 was evaluated as ○, and the case where 1 or more out of 30 was evaluated as Х. A result is shown in Table 1.

The flux compositions of Examples 1 to 15 exhibited superior solder ball retention properties compared to Comparative Example 1 and excellent low residue properties compared to Comparative Example 2. The flux compositions of Examples 1 to 15 are suitable as flux compositions for soldering because they can reduce the amount of residual flux components in the actual process, not only under normal solder bonding conditions but also during rapid heating. Available.

This application claims the priority on the basis of Japanese application Japanese Patent Application No. 2020-066440 for which it applied on April 2, 2020, and inserts all the indication here.

Claims (16)

A flux composition comprising 3-methyl-1,3-butanediol, and an active agent. The method according to claim 1,
The flux composition, wherein the residual amount of the flux composition measured by the following procedure is 10% by weight or less.
(procedure)
When the flux composition was heat-treated from 25°C to 250°C in a nitrogen atmosphere at a temperature increase rate of 5°C/sec, the weight W0 before heating and the weight W1 after heating were measured, and the obtained W0 and W1 were used. , from the formula: W1/W0Х100%, the amount of residue (% by weight) is calculated. The method according to claim 1 or 2,
A flux composition used in a solder bonding process having a temperature increase rate of 3° C./sec or more. 4. The method according to any one of claims 1 to 3,
The flux composition, wherein the activator comprises one or two or more selected from the group consisting of organic acids, amines, halogen activators, and phosphorus activators. 5. The method according to claim 4,
The content of the organic acid in the flux composition is 15% by weight or less;
The content of the amines in the flux composition is 15% by weight or less.
The content of the halogen-based active agent in the flux composition is 10% by weight or less, and
and a content of the phosphorus-based active agent in the flux composition is 10% by weight or less. 6. The method according to any one of claims 1 to 5,
The flux composition, wherein the activator comprises an organic acid having 11 or less carbon atoms. 7. The method according to any one of claims 1 to 6,
A flux composition used in a solder bonding process in an inert gas atmosphere or a reduced pressure atmosphere substantially free of reducing gas. 8. The method according to any one of claims 1 to 7,
A flux composition substantially free of fatty acid amides. 9. The method according to any one of claims 1 to 8,
The flux composition, wherein the content of 3-methyl-1,3-butanediol is 10% by weight or more in 100% by weight of the flux composition. 10. The method according to any one of claims 1 to 9,
The flux composition, wherein the content of 3-methyl-1,3-butanediol is 90% by weight or more in 100% by weight of the flux composition. 11. The method of any one of claims 1 to 10,
A flux composition comprising a solid solvent. 12. The method according to any one of claims 1 to 11,
A flux composition comprising a liquid solvent other than 3-methyl-1,3-butanediol. 13. The method according to any one of claims 1 to 12,
A flux composition comprising a base resin. 14. The method according to any one of claims 1 to 13,
A flux composition for no-clean use. 15. The method according to any one of claims 1 to 14,
A flux composition, wherein the flux composition has a viscosity of 500 mPa·s or more at 25°C, measured in accordance with JIS Z 3284-3: 2014. A solder paste comprising the flux composition of any one of claims 1 to 15 and a metal powder.