Capping a low resistivity metal conductor line or via with a refractory metal allows for effectively using chemical-mechanical polishing techniques because the-hard, reduced wear, properties of the refractory metal do not scratch, corrode, or smear during chemical-mechanical polishing. Superior conductive...http://www.google.de/patents/US5976975?utm_source=gb-gplus-sharePatent US5976975 - Refractory metal capped low resistivity metal conductor lines and vias
