摘要 |
<p>Method for forming a solder bump (42) on a substrate (35) include the steps of forming an under bump metallurgy layer (36) on a substrate, forming a solder bump on the under bump metallurgy layer, and forming an intermetallic portion (33) of the under bump metallurgy layer adjacent the solder bump. In particular, the solder bump has a predetermined shape and this predetermined shape is retained while forming the intermetallic portion of the under bump metallurgy layer. This predetermined shape preferably has a flat surface opposite the substrate thus providing a uniform thickness of solder during the formation of the intermetallic portion. Related structures are also disclosed.</p> |