Fig. 1: Atomic insight and enhanced performances of interface-designed HfO2-based devices.
From: Fatigue-free ferroelectricity in Hf0.5Zr0.5O2 ultrathin films via interfacial design
a Diffusion energy barriers of oxygen vacancy (VO) in the CeO2-x/HfO2 heterostructure. b Schematics of VO migrations in the capacitors based on CeO2-x/HfO2 and bare HfO2 under fields. The arrows colored in cyan and blue denote the applied electric fields in different directions. The spheres highlighted in cyan and blue represent the oxygen vacancies moving forward and backward. The length of the tails, irrespective of color, signifies the mobility of defects in the presence of external electric fields. c Polarization switching barriers for the CeO2-x/HfO2 and bare HfO2 capacitors. d HADDF-STEM image, EELS mappings and Fourier transformation for the CeO2-x/HfO2/LSMO heterostructures. e Coercive fields and remnant polarization values for capped HZO devices. f Cycling performances for the bare Pt/HZO/LSMO device and Pt/CeO2-x/HZO/LSMO capacitor. g Polarization-electric field loops for the Pt/CeO2-x/HZO/LSMO capacitor at different cycling stages. h A comparison of the fatigue and endurance behaviors for the HZO-based capacitors with different capping layers.
