Deposition processes for titanium nitride barrier and aluminum

Embodiments described herein provide a method for forming two titanium nitride materials by different PVD processes, such that a metallic titanium nitride layer is initially formed by a PVD process in a metallic mode and a titanium nitride retarding layer is formed over a portion of the metallic titanium nitride layer by a PVD process in a poison mode. Subsequently, a first aluminum layer, such as an aluminum seed layer, may be selectively deposited on exposed portions of the metallic titanium nitride layer by a CVD process. Thereafter, a second aluminum layer, such as an aluminum bulk layer, may be deposited on exposed portions of the first aluminum layer and the titanium nitride retarding layer during an aluminum PVD process.