Structure and method for making a compliant lead for a microelectronic device

摘要

A method of treating a lead in a chip package. A conductive lead is positioned such that it extends across a gap in a dielectric substrate and is secured at either end to a first surface of the substrate. Directed energy is then applied to a desired portion of the surface of the lead within the gap. As a result of the application of energy, a surface layer of the lead is recrystallized thereby creating a fine grain, dense surface layer of lead material. Surface contaminates may be vaporized and contaminants at the grain boundaries of the recrystallized surface layers may be driven away from the grain boundaries such that a treated lead is more ductile and has better resistance to thermal cycling after the lead has been attached to a chip contact.