A method of fabricating wafer level chip scale packages may involve forming a hole to penetrate through a chip pad of an IC chip. A base metal layer may be formed on a first face of a wafer to cover inner surfaces of the hole. An electrode metal layer may fill the hole and rise over the chip pad. A second...http://www.google.de/patents/US7524763?utm_source=gb-gplus-sharePatent US7524763 - Fabrication method of wafer level chip scale packages
