Preparation of TiN films by plasma assisted atomic layer deposition for copper metallization

This paper describes the effect of plasma pulse time, power, and composition on the electrical properties of TiN prepared by plasma assisted atomic layer deposition. Longer plasma pulse times yielded films of lower resistivity with enhanced stability in air, but resistivity was observed to exponentially decrease to a certain saturated value. Film resistivity also decreased with increasing RF power along with improving the stability. At a fixed power and exposure time, resistivity of the films decreases with increasing hydrogen percentage until up to 40%, and then remained at that value at higher hydrogen percentages. However, the stability was better with samples prepared with low hydrogen percentage.