METHODS AND STRUCTURES FOR A VERTICAL PILLAR INTERCONNECT

摘要

In wafer-level chip-scale packaging and flip-chip packaging and assemblies, a solder cap is formed on a vertical pillar. In one embodiment, the vertical pillar overlies a semiconductor substrate. A solder paste, which may be doped with at least one trace element, is applied on a top surface of the pillar structure. A reflow process is performed after applying the solder paste to provide the solder cap.