Preventing UBM oxidation in bump formation processes

摘要

A method of forming an integrated circuit structure includes forming a copper-containing seed layer on a wafer, and performing a descum step on an exposed surface of the copper-containing seed layer. The descum step is performed using a process gas including fluorine and oxygen. A reduction/purge step is then performed on the exposed surface of the copper-containing seed layer using a nitrogen-containing gas. A copper-containing layer is plated on the copper-containing seed layer.