The invention has an object to provide a flux for rapid heating method used in the rapid heating method such as a laser reflow, the flux being able to suppress any scattering of the solder alloy, and a solder paste for the rapid heating method. The flux contains rosin, a glycol-ether-based solvent, an organic acid, and a thixotropic agent, wherein the solvent is a glycol-based solvent having a low boiling point that is not more than 200 degrees C., content of the solvent having the low boiling point is not less than 20 weight % to not more than 40 weight %. The solder paste is obtained by mixing this flux with solder alloy powder. When the solvent having a high boiling point that is more than 200 degrees C. is further contained, the solvent having the low boiling point of not less than 60 weight % in relation to the whole of the solvent is contained.

A solder composition for use in solder joints of printed circuit boards (PCBs), including a compound layer comprising an alloy of bismuth and tin; and a graphene coating positioned on the compound layer.

A method for fabricating a semiconductor device with a heterogeneous solder joint includes: providing a semiconductor die; providing a coupled element; and soldering the semiconductor die to the coupled element with a first solder joint. The first solder joint includes: a solder material including a first metal composition; and a coating including a second metal composition, different from the first metal composition, the coating at least partially covering the solder material. The second metal composition has a greater stiffness and/or a higher melting point than the first metal composition.

The disclosed solder alloy is useful for plating and for use with electronic components, which are capable of suppressing the formation of external stress-type whiskers. This solder alloy for plating contains Sn and Ni, with the Ni content being 0.06-5.0 mass % inclusive and the remainder including Sn, and is used in electrical contacts that are electrically connected through mechanical joining.

Provided is a manufacturing method in which a coated solder wire having a dense polysiloxane coating film that is uniformly provided over the entire surface of the solder wire can be efficiently obtained in a single process. A coated solder wire is obtained by a manufacturing method that includes; a radicalization step for forming a radicalized organic silicon compound by mixing a reaction gas that has been plasmatized under atmospheric pressure and an organic silicon compound that is introduced by way of a carrier gas, and radicalizing that organic silicon compound; a reaction area formation step for forming a reaction area that is defined by a helical gas flow and in which the radicalized organic silicon compound is uniformly dispersed; and a coating step for forming a 4 nm to 200 nm thick polysiloxane coating film on the surface of a solder wire by transporting a solder wire inside the reaction area and causing the radicalized organic silicon compound to react with metal on the surface of that solder wire.

A solder paste including metal powders, constituted by an alloy powder including bismuth and silver, and a tin powder, the alloy powder including bismuth and silver including silver at a ratio of greater than or equal to 0.1 wt % and less than or equal to 11.0 wt % is provided.

A processor receives solder paste information, where the solder paste information describes a solder paste used in assembly of a printed circuit board. A processor determines a minimum magnetic force required for removing the solder paste from the printed circuit board based on the solder paste information. A processor receives electromagnet information, where the electromagnet information describes an electromagnet used in cleaning of a misprint of the solder paste on the printed circuit board. A processor determines a minimum amount of power to provide the electromagnet to induce the minimum magnetic force in the electromagnet, where the determination of the amount of power is based on the electromagnet information and the minimum magnetic force. A processor adjusts an amount of power applied to the electromagnet to at least the determined minimum amount of power to clean the misprint of the solder paste from the printed circuit board.

With the increasing density of in-vehicle electronic circuits, not only conventional cracks at bonding interfaces such as between the substrate and the solder attachment site or a component and the solder attachment site but also novel cracking problems of cracks occurring in the Sn matrix in the interior of the bonded solder have appeared. To solve the above problem, a lead-free solder alloy with 1-4 mass % Ag, 0.6-0.8 mass % Cu, 1-5 mass % Sb, 0.01-0.2 mass % Ni and the remainder being Sn is used. A solder alloy, which not only can withstand harsh temperature cycling characteristics from low temperatures of −40° C. to high temperatures of 125° C. but can also withstand external forces that occur when riding up on a curb or colliding with a vehicle in front for long periods, and an in-vehicle electronic circuit device using the solder alloy can thereby be obtained.

A processing method of formic acid soldering includes providing a solder, performing a formic acid providing step, performing a soldering step and performing a cooling step. The solder is disposed at a soldering object. In the formic acid providing step, a water-containing formic acid vapor extracted from a formic acid source is introduced to a soldering object so as to form a water-containing formic acid atmosphere surrounding the soldering object. In the soldering step, the solder and the soldering object are soldered in the water-containing formic acid atmosphere at a soldering temperature so as to form a soldered object with high temperature. In the cooling step, the soldered object with high temperature is cooled by a cooling method so as to form a soldered object. A range of a moisture content of the formic acid source is greater than or equal to 0.1 wt % and less than 15 wt %.

A material includes a plurality of supercooled micro-capsules each including a metallic core in a liquid state at a temperature below a solidification temperature of the metallic core and further includes a metallic shell surrounding each respective metallic core. A plurality of alloyed metallic particles and flux are mixed with the plurality of supercooled micro-capsules to form a solder paste. Upon heating the solder paste, the plurality of alloyed particles melt. As the metallic shells destabilize, the liquid metallic cores interdiffuse with the melted alloyed particles forming a new alloy that has a higher melting temperature than the melting temperature of the alloyed metallic particles.