| 摘要 |
In order to achieve finer bump interconnect pitch for integrated circuit packaging, while relieving pressure-induced delamination of upper layer dielectric films, the under bump metallurgy of the present invention provides a pressure distribution pedestal upon which a narrower copper pillar is disposed. A solder mini-bump is disposed on the upper exposed portion of the copper pillar, wherein the solder is softer than the copper pillar. The radius of the copper pillars is selected such that lateral deformation of the solder mini-bumps during final assembly does not form undesired conductive bridges between adjacent pillars.
|
