Electrical characterization of CVD TiN upper electrode for Ta2O5 capacitor

CVD TiN using TiCl4 and NH3 chemistry has been implemented successfully in cylindrically shaped Ta2O3 storage capacitor as a barrier layer in poly-Si/TiN double upper electrode. Electrical characteristics of Ta2O3 capacitor with CVD TiN double electrode were superior to that with PVD TiN and it was attributed to nearly 100% conformality of CVD TiN. However, it was also found that minimizing chlorine content in CVD TiN film was essential to achieve low leakage current level, and in-situ post annealing of CVD TiN film in NH3 ambient was effective in reducing chlorine content.