The stability of dielectric (ZrO2, HfO2) interfaces with germanium was studied. Oxygen diffusion was simulated using a technique that took account of many-body interactions and charge transfer. The results showed that the addition of yttrium was effective in suppressing interfacial oxygen diffusion at ZrO2/germanium interfaces. The addition of yttrium was not effective in suppressing interfacial oxygen diffusion at HfO2/germanium interfaces. The results also showed that diffusion at ZrO2/Ge(111) and HfO2/Ge(111) interfaces was much more suppressed than was diffusion at ZrO2/Ge(001) and HfO2/Ge(001) interfaces.

Molecular-Dynamics Study of Interfacial Diffusion between High-Permittivity Gate Dielectrics and Germanium Substrates. Iwasaki, T.: Journal of Materials Research, 2005, 20[5], 1300-7