Patent ID: 9269682
Filing Date: 2016-02-23
CPC Classification: H01L

Claim Text:
1. A method of forming a bump structure, comprising: forming a passivation layer on a top pad metal region of a semiconductor substrate; forming an opening in the passivation layer to expose a portion of the top pad metal region; forming a first metallization layer on the exposed portion of the top pad metal region by a selective plating process, an edge portion of the first metallization layer conforming to and contacting a top surface of the passivation layer, the first metallization layer being formed directly over the top pad metal region and not extending laterally beyond lateral edges of the top pad metal region; forming a protective layer on the passivation layer and the first metallization layer; forming an opening in the protective layer to expose a first portion of the first metallization layer while leaving covered a second portion of the first metallization layer; forming a second metallization layer on the first portion of the first metallization layer and over a top surface of the protective layer; and forming a solder bump over and electrically connected to the second metallization layer.