Combinatorial screening of work functions in Ta–C–N/HfO2/Si advanced gate stacks

This paper reports a comprehensive investigation into the effects of the C and N contents and temperature anneals on the electrical characteristics of Ta–C–N/HfO2/Si advanced gate stacks (equivalent oxide thicknesses of ∼1.0–1.6 nm) using a combinatorial methodology. The work functions (Φm) of Ta–C–N, with higher C and N, can be tuned up to ∼5.1 eV after 900 °C anneals, suggesting a promising p-type gate metal for complementary metal–oxide semiconductor applications.