A method of forming an interconnect bump structure (32, 33). Under Bumb Metalization 11 (UBM) comprising a chrome layer (16), a copper layer (36), and a tin layer (40) is disclosed. In one embodiment, eutectic solder (45) is then formed over the UBM (11) and reflowed in order to form the interconnect...http://www.google.com/patents/US6107180?utm_source=gb-gplus-sharePatent US6107180 - Method for forming interconnect bumps on a semiconductor die
