Stress and Adhesion of CVD Copper and TiN

The use of copper for interconnect metallization on advanced submicron integrated circuits is attractive because of its inherent low resistivity. To date, chemical vapor deposition (CVD) processes which produce copper films with nearly bulk resistivity and good uniformity have been produced. However, adhesion of the copper deposit to underlying barrier materials, in particular to titanium nitride (TiN), has been problematic. In this work, adhesion has been measured using both a qualitative and a semi-quantitative method and has been correlated with process conditions and precursor formulation.