摘要 |
A solder bump structure for use on a substrate. The solder bump structure includes a multilayer underbump metallization having a major upper surface with a solder wetable caplayer for contacting a solder bump, the mutilayer underbump metallization projecting from the substrate with an exposed sidewall; a thin layer of a metal selected from a group consisting of titanium, chrome, a titanium-nickel-titanium composite, a titanium-nickel-chrome composite, a titanium-platinum-titanium alloy, and a titanium-nickel-oxidized silicon composite deposited over or under the multilayer underbump metallization and covering the exposed sidewall of the multilayer underbump metallization. |