Dielectric dipole mitigated Schottky barrier height tuning using atomic layer deposited aluminum oxide for contact resistance reduction

Abstract

Schottky barrier height tuning is reported from the insertion of thin layers of AlOx and SiO2 at the interface between tantalum nitride and p-type silicon. The magnitude of the change in the barrier height is found to be dependent on the conditions of AlOx and SiO2 formation. The largest change in barrier height is over 350 meV and correlates well with the intrinsic dipole found at this interface. These findings are then interpreted using a model of the dipole formation at the high-κ and SiO2 interface. The application of these findings for low resistance contacts as well as options to achieve greater performance are discussed.