Effect of Ar Sputter Etch on the Texture of Ti and Al/TiN/Ti Metal Stack

The effects of Ar sputter etch and Ti deposition temperature on the crystalline orientation of Ti films deposited by long-throw sputtering geometry are reported. Both Ar sputter etch and high Ti deposition temperature degraded the Ti microstructure from highly (002) Ti textured to mixed (002) Ti and (011) Ti. This degradation produced a wide distribution in the crystalline orientation of Al grains in the Al/TiN/Ti stack. A mechanism based on the effects of Ar sputter etch on the oxide surface roughness and surface chemistry was proposed to explain the effect of Ar etch on the crystalline texture of Ti and Al in the Al/TiN/Ti stack.