JP2011036901A - Solder bonding agent composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solder bonding agent composition containing lead-free solder powder and a thermosetting resin, which has satisfactory solderability and also has high reliability. <P>SOLUTION: The solder bonding agent composition contains lead-free solder powder and thermosetting resin-containing flux, and further contains an inorganic filler with the average particle diameter of 5 to 100 nm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention electrically connects the electrode terminals of various components and the electrodes on the various substrates when mounting the various electronic components on a printed wiring board or the like or mounting the electronic components on the substrate in the assembly of the semiconductor device. Or, it relates to a material to be mechanically bonded.

  Conventionally, with the miniaturization and thinning of electronic devices, excellent electrical conductivity and high bonding reliability have been achieved in the mounting of modularized components and the assembly of various electronic components such as ICs and LSIs. In this respect, solder bonding compositions containing eutectic solder powder of 63Sn / 37Pb (Sn / Pb mass ratio of 63/37) have been widely used. However, in recent years, regulations on lead have been strengthened due to the problem of environmental pollution, and the solder bonding composition containing lead-free solder powder as disclosed in Patent Document 1 below is being switched to.

  However, lead-free alloy solder represented by Sn / Ag / Cu alloy has a melting point that is about 40 ° C higher than that of Sn / Pb-based alloy solder. As a result, a large thermal strain is generated, and there is anxiety in the reliability of the joint.

  In addition, when using a solder bonding composition containing a thermosetting resin, the linear expansion coefficient of the cured product of the thermosetting resin is higher than that of electronic components and substrates, so that the thermal Depending on the factor, there is a problem that cracks occur in the bonding interface and electronic parts, and the bonding reliability is remarkably impaired.

  On the other hand, after soldering, the joint may be reinforced with underfill or mold resin, but from the viewpoint of joint reliability, the underfill or mold resin used has a linear expansion coefficient of these cured products. However, it is desirable to use a material having a small size. In general, as a method of reducing the linear expansion coefficient of a cured resin, a method of adding an inorganic filler having a low linear expansion coefficient such as silica or alumina is known, and has already been applied to the above-mentioned underfill and mold resin. Technology.

JP 2007-136491 A

  However, when a general inorganic filler is added to a solder bonding composition containing a thermosetting resin, the added filler component inhibits the aggregation of the solder, and the solder does not melt, that is, a large amount of solder balls are formed after reflow. There is a problem that fillet formation becomes impossible and as a result, solderability deteriorates. With respect to such problems, conventional solder bonding agent compositions have not been sufficiently studied.

  The present invention provides a solder bonding composition having good solderability and high reliability in a solder bonding composition containing a lead-free solder powder and a thermosetting resin.

  The inventors have found that by adding an inorganic filler having an average particle diameter in a specific range to the solder bonding composition, the solder can be melted without inhibiting the aggregation of the solder, and the present invention is completed. It came to.

  That is, the solder joint composition of the present invention is a solder joint composition containing a lead-free solder powder and a thermosetting resin-containing flux, and contains an inorganic filler having an average particle diameter of 5 to 100 nm. Features.

  According to the solder bonding agent composition of the present invention, the solder can be melted without inhibiting the aggregation of the solder, and therefore a solder bonding agent composition with good solderability can be obtained. Moreover, since the difference of the linear expansion coefficient produced between an electronic component etc. and a junction part can be reduced, a highly reliable solder bonding agent composition can be obtained.

It is a graph which shows the reflow conditions of the solder bonding agent composition containing 42Sn / 58Bi solder powder. It is a graph which shows the reflow conditions of the solder bonding agent composition containing 96.5Sn / 3.0Ag / 0.5Cu solder powder.

  The solder bonding composition of the present invention is a solder bonding composition containing a lead-free solder powder and a thermosetting resin-containing flux, and contains an inorganic filler having an average particle size of 5 to 100 nm. Hereinafter, the components contained in (or can be contained in) the solder joint composition of the present invention will be described.

(Lead-free solder powder)
The lead-free solder powder is a solder metal or alloy powder to which lead is not added. However, the presence of lead as an inevitable impurity in the solder powder is allowed, but in this case, the amount of lead is preferably 100 ppm or less. Specifically, the following can be illustrated as a solder composition which forms lead-free solder.

Pure metal: Ag, Au, Cu, Pt, Pd, W, Ni, Ta, Ti, Cr, Fe, Co, Ga, In, Li, Se, Sn, Bi, Tl, Zn, Te
Binary alloys: Ag-Bi type such as 95.3Ag / 4.7Bi, Ag-Li type such as 66Ag / 34Li, Ag-In type such as 3Ag / 97In, Ag-Te type such as 67Ag / 33Te, 97 Ag-Tl system such as 2Ag / 2.8Tl, Ag-Zn system such as 45.6Ag / 54.4Zn, Au-Sn system such as 80Au / 20Sn, Bi-In system such as 52.7Bi / 47.3In 35In / 65Sn, 51In / 49Sn, 52In / 48Sn etc. In-Sn series, 8.1Bi / 91.9Zn etc. Bi-Zn series, 43Sn / 57Bi, 42Sn / 58Bi etc. Sn-Bi series, 98Sn / 2Ag 96.5Sn / 3.5Ag, 96Sn / 4Ag, Sn-Ag series such as 95Sn / 5Ag, Sn-Zn series such as 91Sn / 9Zn, 30Sn / 70Zn, 99.3Sn / 0 Sn-Cu type such as 7Cu, Sn-Sb type ternary alloy such as 95Sn / 5Sb: Sn-Ag-In type such as 95.5Sn / 3.5Ag / 1In, 86Sn / 9Zn / 5In, 81Sn / 9Zn / Sn-Zn-In series such as 10In, Sn-Ag-Cu series such as 95.5Sn / 0.5Ag / 4Cu, 96.5Sn / 3.0Ag / 0.5Cu, 90.5Sn / 7.5Bi / 2Ag, Sn-Bi-Ag system such as 41.0Sn / 58Bi / 1.0Ag, Sn-Zn-Bi system such as 89.0Sn / 8.0Zn / 3.0Bi Other: Sn / Ag / Cu / Bi system, etc.

  Among these, lead-free solder is made of one or more metals selected from the group consisting of Sn, Cu, Ag, Bi, Sb, In, and Zn, from the viewpoint of obtaining an appropriate melting point as a bonding agent and solder bonding strength. It is preferable to include, and it is more preferable to include one or more metals selected from the group consisting of Sn, Cu, Ag, and Bi.

(Thermosetting resin-containing flux)
The thermosetting resin-containing flux (hereinafter, also simply referred to as “flux”) is not particularly limited as long as it contains a thermosetting resin, and the one used in the conventional solder bonding composition is used. it can. For example, a flux containing a thermosetting resin, an activator, a thixotropic agent, a curing agent, or the like can be used.

<Thermosetting resin>
Examples of the thermosetting resin include an epoxy resin, a phenol resin, a melamine resin, a urea resin, an alkyd resin, and the like, and an epoxy resin is preferable from the viewpoints of curing speed, ensuring a high glass transition temperature, and shear strength.

  Epoxy resins mainly include non-volatile epoxy compounds such as bisphenol A type epoxy resins, novolak type epoxy resins (phenol novolak type epoxy resins, o-cresol novolak type epoxy resins, p-tert-butylphenol novolak type epoxy resins). ), Bisphenol F-type epoxy resin and bisphenol S-type epoxy resin obtained by reacting bisphenol F and bisphenol S with epichlorohydrin, and cycloaliphatic epoxy having cyclohexene oxide group, tricyclodecane oxide group, cyclopentene oxide group, etc. Resin, Phthalic acid diglycidyl ester, Tetrahydrophthalic acid diglycidyl ester, Hexahydrophthalic acid diglycidyl ester, Diglycidyl-p-hydroxybenzoic acid, Dimer Glycidyl ester resins such as acid glycidyl ester, glycidyl amine resins such as tetraglycidyl diaminodiphenylmethane, triglycidyl-p-aminophenol, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, glycerol poly Glycidyl ether, trimethylolpropane polyglycidyl ether, resorcin diglycidyl ether, 1,6 hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, pentaerythritol polyglycidyl Glycidyl such as ether Ether resins, tris (2,3-epoxypropyl) isocyanurate, triglycidyl isocyanurate having a triazine ring such as triglycidyltris (2-hydroxyethyl) isocyanurate, dicyclopentadiene type epoxy resin, adamantane type epoxy resin, etc. Can be mentioned.

  In addition, as an epoxy resin, it is mainly used by blending an epoxy resin that is liquid at normal temperature and a solid epoxy resin at normal temperature, from the viewpoint of maintaining the viscosity when solder is blended in an appropriate range. preferable.

  The content of the thermosetting resin when the entire flux is 100% by mass is preferably 40 to 95% by mass, and more preferably 60 to 90% by mass.

<Activator>
The activator is a component that cleans the metal by reducing oxides, sulfides, hydroxides, chlorides, sulfates, carbonates, etc. present on the metal surface.

  As the activator, non-halogen compounds are preferable from the viewpoint of reducing environmental load, and amines, amine salts (polyamines such as ethylenediamine, organic acid salts of amines such as cyclohexylamine and diethylamine), organic acids, amino acids, Amide compounds and the like are preferable. Specifically, adipic acid, sebacic acid, triethanolamine, monoethanolamine and the like are particularly preferable.

  The content of the activator when the total flux is 100% by mass is preferably 0.5 to 15% by mass, and more preferably 2 to 10% by mass.

<Thixotropic agent>
As the thixotropic agent, conventionally used hydrogenated castor oil, fatty acid amides and the like can be used.

  The content of the thixotropic agent when the entire flux is 100% by mass is preferably 0.5 to 10% by mass, and more preferably 1 to 5% by mass.

<Curing agent>
A hardening | curing agent is a component used as a hardening | curing agent (hardening accelerator) of the thermosetting resin mentioned above, and various hardening agents can be used. For example, as the latent curing agent, NovaCure HX-3722, HX-3721, HX-3748, HX-3088, HX-3613, HX-3921HP, HX-3941HP (Asahi Kasei Epoxy Co., Ltd., trade name), aliphatic polyamine type As for Fujicure FXR-1020, FXR-1030, FXR-1050, FXR-1080 (Fuji Kasei Kogyo Co., Ltd., trade name), As for epoxy resin amine adduct system, Amicure PN-23, MY-24, VDH, UDH , PN-31, PN-40 (Ajinomoto Fine Techno Co., product name), EH-3615S, EH-3293S, EH-3366S, EH-3842, EH-3670S, EH-3636AS (manufactured by Asahi Denka Kogyo Co., Ltd., product) Name). Examples of the imidazole curing agent include 2MZA, 2PZ, C11Z, C17Z, 2E4MZ, 2P4MZ, 2P4MHZ, C11Z-CNS, 2PZ-CNZ (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd.). Of these, the use of an imidazole-based curing agent (particularly an imidazole compound having a hydroxyl group) is preferable because the curing reaction of the thermosetting resin does not proceed rapidly and the generation of stress can be prevented.

  The content of the curing agent when the entire flux is 100% by mass is preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass.

  From the viewpoint of reducing environmental burden, the volatile component (VOC) content of the flux is preferably 1% by mass or less. The VOC content can be obtained by measuring the decrease in mass when the flux is heated from room temperature to 300 ° C. in a nitrogen atmosphere using a differential thermal balance (TG / DTA measuring device).

  From the viewpoint of reducing environmental load, the halogen content of the flux is preferably 1000 ppm or less. The halogen content can be obtained by completely burning the flux, collecting the halogen in the flux in a 0.1% by mass aqueous hydrogen peroxide solution, and then quantifying the halogen by ion chromatography.

  The content ratio of lead-free solder powder and flux (lead-free solder powder: flux) is preferably 60 to 90 mass%: 40 to 10 mass%, more preferably 75 to 85 mass%: 25 to 15 mass%. . By setting it as the said ratio, the viscosity as a paste and thixotropy become favorable, and the solder joint composition suitable for mass production processes, such as printing and dispensing application | coating, is obtained.

(Inorganic filler)
The solder bonding composition of the present invention contains an inorganic filler having an average particle size of 5 to 100 nm in order to improve the bonding reliability by adjusting the linear expansion coefficient of the flux cured product while maintaining good solderability. To do. In the present invention, the average particle diameter of the inorganic filler is a volume-based average particle diameter (D50) measured by Nikkiso Nanotrac UPA-EX150. The measurement conditions are shown below.

(In the case of a specimen in which an inorganic filler is dispersed in a resin: Examples 1 to 7, 9, 10, etc. described later)
Solvent: Propylene glycol monomethyl ether Concentration: 0.5% by mass (as inorganic filler concentration)
Preliminary dispersion: Ultrasonic treatment at 20 kHz for 60 seconds with Ultrasonic Homogenizer manufactured by Nippon Seiki Co., Ltd. Measurement temperature: 20.0 ° C. ± 2.5 ° C.

(When the inorganic filler itself is a sample: Example 8 etc. described later)
Solvent: Water Concentration: 0.5% by mass
Preliminary dispersion: Ultrasonic treatment at 20 kHz for 60 seconds with Ultrasonic Homogenizer manufactured by Nippon Seiki Co., Ltd. Measurement temperature: 20.0 ° C. ± 2.5 ° C.

  From the viewpoint of further improving the bonding reliability, the average particle size of the inorganic filler is preferably 10 nm or more, and more preferably 15 nm or more. On the other hand, from the viewpoint of maintaining better solderability, the average particle size of the inorganic filler is preferably 80 nm or less, and more preferably 50 nm or less. Taking these viewpoints together, the average particle size of the inorganic filler is preferably 10 to 80 nm, and more preferably 15 to 50 nm.

  From the viewpoint of further improving the bonding reliability, the content of the inorganic filler is preferably 2 parts by mass or more and more preferably 5 parts by mass or more with respect to 100 parts by mass of the thermosetting resin in the flux described above. Preferably, it is 20 parts by mass or more. On the other hand, from the viewpoint of maintaining better solderability, the content of the inorganic filler is preferably 100 parts by mass or less, and 90 parts by mass or less with respect to 100 parts by mass of the thermosetting resin in the flux described above. More preferably, it is more preferably 80 parts by mass or less. When these viewpoints are combined, the content of the inorganic filler is preferably 2 to 100 parts by mass, more preferably 5 to 90 parts by mass with respect to 100 parts by mass of the thermosetting resin in the flux described above. More preferably, it is 20-80 mass parts.

  The inorganic filler is not particularly limited as long as it can reduce the difference in the linear expansion coefficient generated between the electronic component and the joint by adjusting the linear expansion coefficient of the flux cured product. Silicon dioxide (silica) Inorganic particles such as aluminum oxide (alumina), calcium carbonate, hydrous magnesium silicate (talc), kaolin clay, barium sulfate, and zeolite can be used. Among these, the use of silicon dioxide particles is preferable because the linear expansion coefficient of the flux cured product can be easily reduced.

  In addition to the above components, the flux contained in the solder bonding agent composition of the present invention or the solder bonding agent composition includes various additives such as surfactants, antifoaming agents, leveling agents and the like as necessary. Additives and the like can be contained. Among these, it is preferable to add a surfactant because solder wettability is improved and dispersibility of the inorganic filler is also improved.

  The solder joint composition of the present invention can be easily produced by kneading together with the above-described essential components and additives added as necessary. At this time, the timing of adding the inorganic filler is not particularly limited, and the flux and lead-free solder powder may be mixed after adding the inorganic filler in the flux as a flux component, or the inorganic filler is added. In advance, flux and lead-free solder powder may be mixed in advance, and an inorganic filler may be added thereto. However, in order to uniformly disperse the inorganic filler in the flux, it is preferable to add the inorganic filler to the flux and then mix the flux and lead-free solder powder.

  Hereinafter, the present invention will be described in more detail with reference to examples. These examples are examples of the best mode of the present invention, but the present invention is not limited by these examples.

Example 1
Resin composition in which silica particles with an average particle size of 50 nm (50% by mass) are dispersed in liquid bisphenol A type epoxy resin (50% by mass) (product name: 50% by weight 50 nm silica dispersed bisphenol A type epoxy resin, manufactured by Admatechs) ) 65% by mass, bisphenol A type thermosetting resin (DIC Corporation, EPICLON860) 22% by mass, thixotropic agent (Shin Nippon Rika Co., Ltd., Gelol D) 2% by mass, activator (adipic acid) 5% by mass , 2% by mass of surfactant (BYK361N, manufactured by BYK Japan), 1% by mass of antifoaming agent (Floren AC303, manufactured by Kyoeisha Chemical Co., Ltd.), and 2-phenyl-4-methyl-5-hydroxy as a curing agent Methylimidazole (2P4MHZ) 3% by mass was weighed in the same container and mixed using a rough machine to obtain a flux. Various physical property evaluations to be described later were performed using the obtained flux. In addition, the flux obtained by the same method as described above and 42Sn / 58Bi solder powder are weighed at a ratio of flux: solder powder = 20: 80, and these are mixed in a kneader for 2 hours to perform solder bonding. An agent composition was prepared. Various physical property evaluations to be described later were performed using this solder bonding agent composition. The component composition and evaluation results of Example 1 are shown in Table 1. In Table 1, “silica particle content (parts by mass) with respect to 100 parts by mass of resin” refers to bisphenol A type epoxy resin in 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin and bisphenol A type thermosetting resin ( EPICLON860) means the silica particle content (parts by mass) when the total is 100 parts by mass. The same applies to the following examples.

(Example 2)
In the preparation method of Example 1, the blending amount of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin was 50% by mass, and the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 37% by mass. In the same manner as in Example 1, flux and solder bonding agent compositions were prepared, and various physical property evaluations described later were performed.

(Example 3)
In the preparation method of Example 1, except that the blending amount of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin was 35 mass% and the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 52 mass%. In the same manner as in Example 1, flux and solder bonding agent compositions were prepared, and various physical property evaluations described later were performed.

Example 4
In the preparation method of Example 1, the blending amount of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin was 20% by mass, and the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 67% by mass. In the same manner as in Example 1, flux and solder bonding agent compositions were prepared, and various physical property evaluations described later were performed.

(Example 5)
In the preparation method of Example 1, instead of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin, silica particles having an average particle size of 25 nm (50% by mass) are dispersed in liquid bisphenol A type epoxy resin (50% by mass). A flux and solder bonding agent composition was prepared in the same manner as in Example 1 except that a resin composition (manufactured by Admatechs Co., Ltd., product name: 50 wt%, 25 nm silica-dispersed bisphenol A type epoxy resin) was used. Various physical properties were evaluated.

(Example 6)
In the preparation method of Example 1, instead of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin, silica particles having an average particle size of 15 nm (50% by mass) are dispersed in liquid bisphenol A type epoxy resin (50% by mass). A flux and solder bonding agent composition was prepared in the same manner as in Example 1 except that the resin composition (manufactured by Admatechs Co., Ltd., product name: 50 wt%, 15 nm silica-dispersed bisphenol A type epoxy resin) was used. Various physical properties were evaluated.

(Example 7)
A flux was prepared in the same manner as in the preparation method of Example 1, and various physical property evaluations described later were performed. Further, in the preparation method of Example 1, the solder bonding agent composition was the same as Example 1 except that 96.5Sn / 3.0Ag / 0.5Cu solder powder was used instead of 42Sn / 58Bi solder powder. The material was prepared and various physical property evaluations mentioned later were performed.

(Example 8)
In the preparation method of Example 1, the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 54.5% by mass, and silica having an average particle diameter of 50 nm instead of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin. A flux and a solder bonding agent composition were prepared in the same manner as in Example 1 except that the particles (32.5% by mass) were used, and various physical property evaluations described later were performed.

Example 9
In the preparation method of Example 1, the blending amount of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin was 77.5% by mass, and the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 9.5% by mass. In the same manner as in Example 1, flux and solder bonding agent compositions were prepared, and various physical property evaluations described later were performed.

(Example 10)
In the preparation method of Example 1, the blending amount of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin was 4 mass%, and the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 83 mass%. In the same manner as in Example 1, flux and solder bonding agent compositions were prepared, and various physical property evaluations described later were performed.

(Comparative Example 1)
In the preparation method of Example 1, except that 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin was not used and the blending amount of bisphenol A type thermosetting resin (EPICLON860) was set to 87% by mass, A flux and solder bonding agent composition was prepared in the same manner as in Example 1, and various physical property evaluations described later were performed.

(Comparative Example 2)
In the preparation method of Example 1, the blending amount of bisphenol A type thermosetting resin (EPICLON860) was 54.5% by mass, and the average particle size was 0.5 μm instead of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin. A flux and a solder bonding agent composition were prepared in the same manner as in Example 1 except that silica particles (32.5% by mass) were used, and various physical property evaluations described later were performed.

(Comparative Example 3)
In the preparation method of Example 1, the blending amount of bisphenol A type thermosetting resin (EPICLON860) was set to 70% by mass, and an average particle size of 0.5 μm was used instead of 50 wt% 50 nm silica-dispersed bisphenol A type epoxy resin. A flux and a solder bonding agent composition were prepared in the same manner as in Example 1 except that silica particles (17% by mass) were used, and various physical property evaluations described later were performed.

(1) Measurement of linear expansion coefficient Oven which was obtained by uniformly applying the obtained flux onto a polyethylene terephthalate (PET) film using a bar coater to a thickness of 50 μm ± 10 μm and maintaining the furnace temperature at 190 ° C. And cured for 90 minutes. The obtained cured coating film was peeled off from the PET film, and the linear expansion coefficient (α1, α2) was measured for a sample cut into a size of 5 mm × 20 mm using a TMA apparatus (SS6000) manufactured by SII.

(2) Glass transition temperature The extrapolated point (starting point of the first endotherm) of the temperature-TMA curve obtained when measuring the linear expansion coefficient in (1) was taken as the glass transition temperature (Tg) of the sample.

(3) Measurement of elastic modulus A cured coating film was prepared on a PET film by the same method as the linear expansion coefficient measurement in (1), and this was peeled off from the PET film and cut into a size of 5mm x 30mm. Using an autograph (AGS-G), the elastic modulus was measured under the condition of a pulling speed of 5 mm / min.

(4) Measurement of breaking strength Using a SHIMADZU autograph (AGS-G), measure the breaking strength of the sample prepared by the same method as the elastic modulus measurement in (3) under the condition of a pulling speed of 5 mm / min. did.

(5) Evaluation of the gloss of the solder The obtained solder bonding composition was applied to a land for QFP (Quad Flat Package) (0.8 mm pitch) formed on a glass epoxy substrate using a metal mask having a thickness of 200 μmt. An example using 42Sn / 58Bi solder powder printed with a squeegee and heated under the reflow conditions shown in FIG. 1, and an example using 96.5Sn / 3.0Ag / 0.5Cu solder powder as shown in FIG. A sample was prepared by heating under conditions. About the obtained sample, the gloss of the solder was visually observed and evaluated according to the following criteria.
○: Glossy △: Some glossy ×: No gloss

(6) Evaluation of Solder Ball Presence (Fillet Formability) For the sample used for the solder gloss evaluation of (5), visually observe the presence or absence of solder balls generated in the residual film between the pins (between lands). Evaluation was made according to the following criteria.
○: Solder balls are hardly generated Δ: Solder balls are generated ×: Fillet cannot be formed

(7) Measurement of shear strength Copper solder lands (conductor dimensions: 0.85 x 0.55 mm, conductor spacing: 0.85 mm) formed on a glass epoxy substrate were coated with the obtained solder bonding composition on a metal mask with a thickness of 150 µmt. A 1608 CR chip plated with a metal squeegee was placed on the printed film of the copper foil lands (10 pieces) one by one. And it heated on the reflow conditions similar to the glossiness evaluation of the solder of (5), and produced the test piece. About this test piece, the shear strength of the chip | tip was measured on condition of 5 mm / min using the tensile tester (EZ-L by SHIMADZU). In addition, the result of Table 1 is an average value of 10 chips | tips which measured shear strength.

(8) Measurement of the shear strength after the thermal shock test For the test piece prepared by the same method as the measurement of the shear strength in (7), the thermal shock test was performed using a thermal shock tester (TSA-71H-W) manufactured by ESPEC. Thereafter, the shear strength was measured by the same method as the measurement of the shear strength in (7). The thermal shock test was performed for 3000 cycles, with one cycle consisting of exposure at 40 ° C. for 15 minutes and then exposure to 125 ° C. for 15 minutes. In addition, the result of Table 1 is an average value of 10 chips | tips which measured shear strength.

  As shown in Table 1, in the examples of the present invention, the evaluation of “solder gloss” and “presence / absence of solder balls (fillet formation)” is better than that of the comparative example, and “shear strength” and “cooling / heating” High results were also obtained for “shear strength after impact test”. Therefore, according to this invention, it turned out that solderability is favorable and a reliable solder bonding agent composition is obtained. In particular, regarding “shear strength after a thermal shock test”, Examples 1 to 9 in which silica particles were added within a range of 5 to 90 parts by mass with respect to 100 parts by mass of the thermosetting resin were excellent.

Claims (5)

A solder joint composition containing a lead-free solder powder and a thermosetting resin-containing flux,
A solder joint composition comprising an inorganic filler having an average particle diameter of 5 to 100 nm.   The solder bonding agent composition according to claim 1, wherein the inorganic filler has an average particle size of 15 to 50 nm.   The solder bonding agent composition according to claim 1 or 2 whose content of said inorganic filler is 5-90 mass parts to 100 mass parts of thermosetting resin in said thermosetting resin content flux.   The solder bonding agent composition according to claim 1, wherein the inorganic filler is silicon dioxide particles.   The solder bonding agent composition according to any one of claims 1 to 4, wherein the lead-free solder powder contains one or more metals selected from the group consisting of Sn, Cu, Ag, Bi, Sb, In, and Zn. object.

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