An integrated circuit (IC) package substrate has a dielectric layer and a micro filled via formed substantially in the center of a hole in the dielectric layer. The IC package substrate has at least one chip bonding pad and one ball attach pad that are electrically coupled to each other by the micro...http://www.google.de/patents/US6034427?utm_source=gb-gplus-sharePatent US6034427 - Ball grid array structure and method for packaging an integrated circuit chip
