SUBSTRATE METALLIZATION AND BALL ATTACH METALLURGY WITH A NOVEL DOPANT ELEMENT

摘要

Surface-active dopants are added to a portion of a circuit package before a reflow process to promote wetting and reduce the formation of solder bump bridges. The circuit package has a solder element that electrically connects the circuit package to a substrate. A reflow process is performed to attach the solder element to a pad on the circuit package. During the reflow process, the surface-active dopants diffuse to the surface of the solder element and form an oxide passivation layer on the surface of the solder element.