A PVD based barrier technology for the 45Â nm node

A new PVD source for barrier deposition has been developed which is extendible down to the 45 nm node. The source can conformally deposit barrier metal on the sidewalls of vias and trenches. The thickness of the barrier on the via bottom can be minimized for lowest via resistance. Electrical tests on typical back-end-of-line structures show line resistances consistent with measured trench sidewall coverage. Both stress migration and electro-migration performance are superior to previous generation PVD barrier sources.