Method of electrodepositing gold on a copper seed layer to form a gold metallization structure

摘要

An electrically conductive barrier layer is formed on a semiconductor substrate such that the barrier layer covers a first device terminal. A seed layer is formed on the barrier layer. The seed includes a noble metal other than gold. The substrate is masked so that a first mask opening is laterally aligned with the first terminal. An unmasked portion of the seed layer is electroplated using a gold electrolyte solution so as to form a first gold metallization structure in the first mask opening. The mask, the masked portions of the seed layer, and the barrier layer are removed. The noble metal from the unmasked portion of the seed layer is diffused into the first gold metallization structure. The first gold metallization structure is electrically connected to the first terminal via the barrier layer.