Fig. 4: Formation energies and polarization switching energy barriers in HZO with/without La doping.
From: Approaching theoretical polarization limit in HfZrO2/HfLaO2 multilayers
Calculated formation energies of the o-, m- and r3m-phases of HZO as functions of in-plane with lattice parameters under (a) stoichiometric conditions (no oxygen vacancies) and (b) 4.17% concentration of oxygen vacancies. c Schematic illustration of two 180° polarization switching pathways: the conventional non-crossing path (N-path), where threefold coordinated oxygen atoms do not cross the Hf atomic plane, and the unconventional crossing traversal path (T-path), where they do. Calculated electric polarization values for both paths are also presented. d Calculated energy barriers for the N- and T-path switching under strain-free, – 1% compressive, and + 1% tensile strain conditions. e Energy profiles of N- and T-path switching in HZO films with 6.0% and 25% La doping concentrations.
