| abstract |
A semiconductor device comprises a semiconductor substrate, an under-bump metallization (UBM) structure overlying the semiconductor substrate, and a solder bump overlying and electrically connected to the UBM structure. The UBM structure comprises a first metallization layer comprising a first metal, a second metallization layer comprising a second metal different from the first metal, and a first intermetallic compound (IMC) layer between the first metallization layer and the second metallization layer, the first IMC layer comprising the first metal and the second metal. |