Te-induced modulation of the Mo/HfO2 interface effective work function

First principles calculations of the impact of Te local doping on the effective work function of a Mo/HfO2 interface are presented. The undoped interface has a p-type effective work function. We find that interstitial Te and Te in the metal both make the effective work function more p-type. More importantly, Te substituting for O or Hf in the dielectric near the interface-energetically stable for all growth conditions-decreases the effective work function, making it more n-type. (c) 2008 American Institute of Physics.