Local Dielectric Property of Hafnium and Lanthanum Atoms in HfLaO_x

Abstract

In this work, we investigate the electronic contribution to local dielectric property of La 2 O 3 and HfO 2 using cluster models. The relation between the coordinate number of metal atoms and their bonding energy shows a hint that hafnia takes the cubic structure by the incorporation of La 2 O 3 in HfO 2 . The local properties of polarizability and dielectric constant of La 2 O 3 and HfO 2 are closely similar to each other. It is considered to be one of the reasons why the incorporation of lanthanum atoms does not lower the permittivity of HfO 2 . We confirm this by the study of the local dielectric property of the HfLaO x cluster model. We compare the dielectric properties around an oxygen atom and that between the oxygen atom and a next metal atom. Our results show that the contribution to the dielectric response from the bond regions is not so large.