Abstract: Copper-containing surfaces, such as a copper surface for use in an electrical circuit, are protected by the provision of a bismuth coating.

Abstract: A rosin-free, low VOC, no-clean soldering flux consists essentially of one or more halide-free carboxylic acid activators in an aggregate amount not exceeding about 8% by weight of the flux; one or more alkyl amines capable of forming amine salt of the one or more activators and in an aggregate amount not exceeding about 10% by weight of the flux; and water, with or without a surfactant. The flux is particularly useful in a method of producing soldered printed wiring assemblies with minimal residual ionic contamination, so that post-soldering cleaning of the assemblies is unnecessary.

Abstract: Electroconductive resin adhesive particles are incorporated in a dielectric-resin-adhesive-containing carrier to form a Z-axis adhesive. Particles are preferably produced by printing techniques or by in-fluid forming techniques, the latter being particularly suited for the formation of substantially spherical particle shapes. The particles also have use as discrete adhesive members.

Abstract: A no-clean soldering flux consists essentially of one or more halide-free, water soluble activators in an aggregate amount not exceeding about 5% by weight of the flux, a water soluble fluorinated surfactant in an amount not exceeding about 1% by weight of the flux, and water. The flux is substantially VOC-free and is particularly useful in a method of producing soldered printed wiring assemblies with minimal residual ionic contamination, so that post-soldering cleaning of the assemblies is unnecessary. The absence of significant amounts of VOC's and the elimination of post-soldering cleaning result in substantial environmental and production-related benefits.

Abstract: A solder preform comprises a body of solder material having at least three legs extending outwardly from a generally central base portion. In a method of use, the preform is disposed between two solderable surfaces (such as the metalized undersurface of a semiconductor die and a support surface therefor), heated above the solder melting point to cause the solder to flow between the surfaces, and then cooled to solidify the solder and effect the bond. The preform configuration is such that the melting solder flows generally outward from the central base portion to expel gases from between the surfaces to be bonded.

Abstract: A solder alloy which is particularly effective for use in automotive radiator applications comprises 87.5%-96.5% lead, 3%-10% tin, 0.5%-2.0% antimony, and 0-0.5% silver. The solder has high mechanical strength, is resistant to galvanic corrosion, and is readily solderable.