The object of the present invention is to provide a flux composition and a solder paste composition in which scattering of flux is suppressed.

A flux composition comprising an anti-scattering agent represented by formula (1) below,

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wherein Z is optionally substituted alkylene, R.sup.1 and R.sup.2 are each independently optionally substituted alkyl, optionally substituted aralkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, or optionally substituted heterocycloalkyl, R.sup.3 and R.sup.4 are each independently optionally substituted alkyl.

Provided is a joint manufacturing method including: a step A of preparing a laminate in which two objects to be joined are temporarily adhered with a heat-joining sheet including a pre-sintering layer interposed between the two objects to be joined; a step B of increasing a temperature of the laminate from a temperature equal to or lower than a first temperature defined below to a second temperature; and a step C of holding the temperature of the laminate in a predetermined range after the step B, in which the laminate is pressurized during at least a part of the step B and at least a part of the step C. The first temperature is a temperature at which an organic component contained in the pre-sintering layer is decreased by 10% by weight when the pre-sintering layer is subjected to thermogravimetric measurement.

Provided herein is a solder paste that can be used for solder connection requiring a high melting point, while, at the same time, ensuring excellent applicability, high adhesion, and excellent solder joint reliability. A mount structure mounting an electronic component with such a solder paste is also provided. The solder paste is a solder paste that includes a solder powder and a flux. The flux contains an epoxy resin, a phenolic resin, a benzooxazine compound, and an activating agent. The phenolic resin contains at least one type of phenolic resin having a phenolic hydroxyl group and an allyl group within the molecule.

The purpose is, in mounting a semiconductor device onto a substrate, to make it easy to identify the remaining amount of an auxiliary joining agent, to stabilize the dispensing amount of the auxiliary joining agent, and to prevent a shortage of the auxiliary joining agent. Also for the purpose of efficient maintenance of a mounting machine, provided is an auxiliary joining agent adapted to aid joining of metals and prepared by dissolving a colorant in a solvent having a reducing property of removing an oxide film on a metal surface. The auxiliary joining agent is produced by a method including a step of mixing a solvent having a reducing property of removing an oxide film on a metal surface, and a colorant having a property of dissolving in the solvent.

The disclosure describes techniques for eliminating or reducing non-wet open (NWO) defect formation by using a low activity flux to prevent a solder paste from sticking to ball grid array (BGA) solder balls during reflow soldering. The low activity flux may be configured such that: i) it creates a barrier that prevents the solder paste from sticking to the solder balls of the BGA; and ii) it does not impede the formation of solder joints during reflow. In implementations, a solid coating of the low activity flux may be formed over balls of the BGA, and the BGA may then be bonded to a PCB during reflow. In implementations, the balls of a BGA may be dipped in a low-activity creamy or liquid flux prior to reflow. In some implementations, the flux may applied on a solder paste printed on pads of the PCB, followed by placement of a BGA.

A conductive paste including (A) a silver powder, (B) a glass frit, (C) an organic binder and (D) a powder containing Cu and at least one metal element selected from the group consisting of V, Cr, Mn, Fe and Co. The powder (D) may thus contain Cu and Mn, Cu and Fe or Cu and Co. The conductive paste has a desirable electromigration resistance, solder heat resistance and adhesiveness to a substrate.

The present invention is a composite welding wire for fusion welding of components manufactured of superalloys. The composite weld wire includes a surface layer applied to the core wire in a green condition and bonded to the core wire. The surface layer includes alloying elements selected from among B and Si, the total bulk content of B and Si representing 0.5 to 4.0 wt. % of the composite welding wire. The boron and silicon alloying elements reduce the melting temperature and increase the solidification range of the weld pool, minimizing the incidence of weld cracking compared to welding without the coating. The green condition surface layer is comprised of more than 80 wt. % of the bulk content of the composite welding wire selected from the combination of B and Si.

The present invention relates to a metal paste including: a first metal powder including nickel (Ni); a second metal powder including at least one selected from the group consisting of tin (Sn), zinc (Zn), bismuth (Bi), and indium (In); and a dispersing agent, and to a thermoelectric module which adopts a bonding technique using the metal paste.

Intercalation pastes for use with semiconductor devices are disclosed. The pastes contain precious metal particles, intercalating particles, and an organic vehicle and can be used to improve the material properties of metal particle layers. Specific formulations have been developed to be screen-printed directly onto a dried metal particle layer and fired to make a fired multilayer stack. The fired multilayer stack can be tailored to create a solderable surface, high mechanical strength, and low contact resistance. In some embodiments, the fired multilayer stack can etch through a dielectric layer to improve adhesion to a substrate. Such pastes can be used to increase the efficiency of silicon solar cells, specifically multi- and mono-crystalline silicon back-surface field (BSF), and passivated emitter and rear contact (PERC) photovoltaic cells. Other applications include integrated circuits and more broadly, electronic devices.

The invention described herein pertains generally to a process for making boric acid free flux compositions in which boric acid and/or borax is substituted with a molar equivalent amount of potassium tetraborate tetrahydrate. In some embodiments, a phthalocyanine pigment is used to affect a color change at activation temperature.