Dielectric properties of Er- doped HfO2 (Er∼15%) grown by atomic layer deposition for high- κ gate stacks

Abstract

Er- doped HfO2 (Er∼15%) films are grown by atomic layer deposition on Si(100). The characteristics of the doped oxide are compared with those of HfO2. In Er- doped HfO2, the stabilization of the cubic structure, together with the effect of the high polarizability of Er 3+, allow to obtain a dielectric constant of ∼33 after annealing at 900 °C. The insertion of Er within the metallic sublattice of HfO 2 reduces the net density of fixed charges, due to the creation of oxygen vacancies. For similar equivalent oxide thickness, lower leakage currents are measured for Er- doped HfO2 than for HfO2. © 2010 American Institute of Physics.