Bottom up deposition of advanced iPVD Cu process integrated with iPVD Ti and CVD Ru

We describe a novel development of bottom up deposition in the advanced Ionized Physical Vapor Deposition (iPVD) Cu process integrated with iPVD Ti and Chemical Vapor Deposition (CVD) Ru. Combination of CVD Ru and iPVD Cu processes provided us void free Cu filling with enlarging Cu grain size. CVD Ru film had superior wettability to Cu without alloy formation. Cu deposition thickness on field area was controlled by adjusting both Cu- and Ar-ion amount. Then Cu migrated on side wall surface toward trench bottom by Ar-ion bombardment and thermal energy avoiding the risk of pinch-off. Cu grain size inside trench was larger than conventional plated Cu. In addition, electrical performance indicated lower wiring resistivity with iPVD Cu filling using CVD Ru liner.