Patent ID: 7703661

Claim:
A method for inducing nucleation sites in a solder alloy, said method comprising: predetermining a desired undercooling temperature characteristic for a solder composition; selecting at least one nucleating modifier to produce the desired undercooling temperature with relatively uniform crystallite distributions with random orientations when the solder composition freezes to a solid joint, the nucleating modifier comprises a dimension that avoids point inhomogeneities in the solid joint; adding the nucleating modifier which has been selected to the solder composition in sufficiently small quantities such that a concentration thereof comprises a small fraction of a percent by weight of the solder composition, wherein the nucleating modifier is added to a portion of the solder composition; and undercooling the solder composition to freeze the portion of the solder composition comprising the nucleating modifier thereby transforming it into a solid state while a remaining portion of the solder composition without the nucleating modifier remains in a liquid state.